Patent Application
20090081061
Oscillating vane machines (OVMs) have been described in the art and have the potential to provide high flow rates and pressures but, in order to do so; they require configurations, such as vane actuation and valving, suitable for high speed operation. See U.S. Pat. No. 2,257,884, issued Oct. 7, 1941 to Mize; U.S. Pat. No. 2,393,204, issued Jan. 15, 1946 to Taylor; U.S. Pat. No. 4,099,448, issued Jul. 11, 1978 to Young; U.S. Pat. No. 4,823,743, issued Apr. 25, 1989 to Ansdale; and U.S. Pat. No. 4,080,114, issued Mar. 21, 1978 to Moriarty; the contents of which are incorporated herein by reference in their entirety.
The machine of Mize places a plurality of oscillating vanes in a common main chamber and relies on the ability of the vanes to seal against each other at their pivots to prevent high pressure fluid from leaking to low pressure areas. This type of seal is, at best, a line contact and is insufficient for high pressures. In Mize, the oscillating vanes are actuated via a continuously rotating crankshaft like, as known to those skilled in the art, those used in reciprocating piston machines. The fluid enters and exits the chambers through fixed, radially positioned ports which are covered and uncovered by the distal ends of the vanes as they oscillate. The fluid path of this machine is very much like that of two-stroke reciprocating piston engines where an incoming charge of fresh air is used to expel a previously combusted charge of exhaust gas. As such, the porting arrangement of Mize does not allow the oscillating vanes to provide an efficient inlet process by themselves; therefore, Mize utilizes an integrated centrifugal blower to charge the chambers with fresh air. Mize's preferred embodiment utilizes 4 oscillating vanes driven via a crankshaft with an individual crank throw for each of the 4 vanes.
Taylor discloses an oscillating vane machine used as a hydraulic motor whereby a single vane is contained within a single main chamber thereby making it more practical to seal the vane and its pivot. This type of arrangement is better suited for higher pressures; however, the actuation of a single oscillating vane at high speed will produce excessive vibration unless a counterbalance is used.
Young discloses a two-vane machine driven via a gear set and over-running clutches on the shaft of each vane. Over-running clutches do not provide reliable synchronized motion as is required by oscillating vane machines at high speed. In one embodiment a pair of rotary valves is disclosed to control the flow of fluid into and out of the machine. In yet another embodiment, Young utilizes a complicated series of rotary valves in conjunction with poppet valves. Every time a fluid passes through a valve, it loses energy and represents a source of inefficiency. In this embodiment, the fluid must pass through no less than five valves per circuit representing a highly inefficient fluid path. Poppet valves, however, have the advantage of being able to seal by pressure loading without generating friction.
Ansdale discloses a single vane machine whereby the vane is driven via a crankshaft with a separate counterbalance to reduce vibration. In one embodiment, Ansdale uses pressure activated reed valves. In another embodiment is disclosed a cam and spring actuated poppet valves with timed opening and closing, and in a third embodiment rotary valves are used with timed opening and closing.
Moriarty discloses a machine whereby two diametrically opposed vanes are attached to a single pivot. He calls this assembly a piston assembly and shows one embodiment, which utilizes one piston assembly, and another embodiment which utilizes two piston assemblies. He also discloses improvements on a nutating drive mechanism with a continuously rotating input/output shaft, used to actuate the oscillating piston assemblies. Moriarty also discloses a novel flow path for the fluid entering the piston chambers through the vane pivots and then through the vanes themselves with the opening and closing of the ports in the vanes being controlled with a flapper valve activated by inertia and pressure differences. He also uses various reed valves in additional embodiments for fluid inlet and discharge. As with all of the previous machines, Moriarty does not provide a fluid path which will support high flow rates while keeping the machine small.
In the self-balancing, centrally pivoting oscillating vane machines described by Chomyszak and disclosed in copending U.S. Provisional Application Nos. 60/889,315 filed on Feb. 12, 2007 and 60/846,543 filed on Sep. 22, 2006 (both of which are incorporated by reference herein in their entirety), in order to reduce stresses in the drive mechanism, the vane pivots must be pushed farther apart.
CAES, compressed air energy storage; DRIV, Dragonfly rotating or rotary inlet valve; EMP, Energy Management Program; LSE, load serving entities; OVM, oscillating vane machine; OVMC, oscillating vane machine compressor; OVME, oscillating vane machine expander.
The present invention is directed to a peripherally pivoted oscillating vane machine (OVM) which can be adapted for use either as a compressor or as an expander and which has the potential to produce high flow and high pressures from small and inexpensive packages. More specifically, the present invention relates to a machine comprising superior elements of vane 2 construction, placement and phasing; valve 18 actuation and external surface porting which allows the oscillating vane machine to operate at higher speeds and provide significant increases in flow rate, efficiency and flexibility.
The peripherally pivoted OVM of the present invention maintains the compactness of OVM but reduces loads on the drive mechanism as compared to other multi-vane machines disclosed in the art. Hence, in many ways, the present invention is a dramatic departure from oscillating vane machines known in the art, including those previously disclosed by Chomyszak.
Specifically, it is an object of the present invention to provide an oscillating vane machine (OVM) where the vanes 2 can be operated at high speed and with minimum mechanical loads by locating the vane pivot shafts 7 at an increased distance from the drive mechanism axis to allow space for a larger drive mechanism, of favorable geometry, capable of transmitting more power to the vanes 2 while maintaining reasonable mechanical loads and overall compactness of design.
In one embodiment, the present invention provides an oscillating vane machine comprising (a) a stator 1 having a central stator axis; (b) a plurality of main chambers 16 housed in said stator 1 and arranged about said central stator axis; (c) a plurality of peripherally pivoted vanes 2, wherein each one of said plurality of peripherally pivoted vanes 2 is positioned in one of said plurality of main chambers 16; (d) at least one drive mechanism which drives one or more of said plurality of peripherally pivoted vanes 2; (e) at least one inlet port 8 in fluid communication with each main chamber 16; and (f) at least one discharge port 9 in fluid communication with each main chamber 16.
In one embodiment, the improvements in OVMs are accomplished with modifications and optimization of the phasing of the machine and utilizing any of several drive mechanisms. Accordingly it is an object of the invention to provide de-phased actuation of the peripherally pivoted vanes 2 so as to minimize pulsation effects in the suction and discharge fluid paths and to reduce the magnitude of torque peaks in the drive mechanism. However, the actuation of the vanes 2 need not be completely de-phased and may in certain circumstances be phased.
Another object of the invention is to provide an oscillating vane machine with improved porting [8][9] configurations as well as valve 18 actuation and control.
In one embodiment, the present invention provides an OVM wherein the inlet 8 and discharge 9 ports are located or positioned at one or more external surfaces of the oscillating vane machine. In this embodiment the inlet 8 and/or discharge 9 ports may be valves 18 and these valves 18 may further be servo-actuated rotary valves 43.
In another embodiment, the inlet 8 and/or the discharge 9 ports may also be configured such that they are centrally located.
Another object of the invention is the selection and implementation of the appropriate drive mechanism for an application. In one embodiment, the drive mechanism or driver is a master/slave radial drive mechanism 54.
In another embodiment the drive mechanism or driver is a crank rocker with gears 28.
In another embodiment the drive mechanism or driver is a crank slider with gears 27.
In another embodiment the drive mechanism or driver is a scotch yoke 29.
In another embodiment the drive mechanism or driver is a crank slider with linkage 53.
The OVMs of the present invention may further comprise a pair of fluid inlet ports 8 and a pair of discharge ports 9 provided in each of said plurality of main chambers 16.
The main chambers 16 of the OVMs of the present invention may be configured in any number of arrangements provided that at least two of the chambers 16 are configured to contain peripherally pivoted vanes 2. In one embodiment, the plurality of main chambers 16 is in a unidirectional configuration. In another embodiment, they are configured in an alternating pattern.
The present invention also provides the manufacture of an integrated vane 2 and shaft 7 assembly which comprises at least (a) a vane 2 body having an integral shaft 7, (b) one or more end caps 11 for attachment to each end of said vane 2 body, and (c) seal glands 10, wherein said seal glands 10 are provided on the outer surfaces of (a) and (b).
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of the embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
A description of the preferred embodiments of the invention follows.
As has been appreciated in the prior art, and in earlier work performed by Chomyszak, the OVM provides a remarkable ratio of capacity to compress or expand fluid compared to its size and weight. Applicants have discovered that what limits the OVM from achieving its potential is that the loads imparted onto the drive mechanisms which interface with the oscillating vanes 2 can be extremely high.
For a given power level, there are four ways to improve the drive mechanism such that it is capable of withstanding the power being transmitted through it: 1) use stronger materials, 2) use larger components, 3) reduce the loads or 4) modify component geometry. The work performed thus far in designing, analyzing, building, and testing a working OVM has shown that the loads on the components are created by three sources: friction, inertia and pressure differential.
The frictional component is relatively small compared to the other sources and those skilled in the art understand that there are numerous ways to reduce friction.
The inertial component is produced by the very nature of oscillation whereby a mass must be accelerated in one direction, decelerated to a complete stop, accelerated in the opposite direction, decelerated to a stop, and ad infinitum. The loads due to inertia are a function of the mass of the components, their dimensions, and the rate(s) of acceleration and deceleration.
The loads produced by the pressure differential between the high pressure side of the vane 2 and the low pressure side of the vane 2 are directly proportional to the magnitude of the pressure difference and the area over which it is applied, and is directly related to the dimensions and size of the vane 2. The magnitude of pressure differential is determined by the application that the OVM is being designed for.
The combined loads due to friction, inertia and pressure differential result in a resisting torque on the oscillating vane 2 that must be overcome with the drive mechanism in the case of a compressor. In the case of an expander, energy is put into the drive mechanism via the pressure differential and is taken out of the drive mechanism by the friction, vane inertia and the external load that is attached to the expander.
Given that inertial loads and loads due to pressure differential are directly associated to vane 2 size and dimension, it is important to note that the dimensions of the vane 2 are chosen to create a suitable chamber 16 or chamber volume in which the vane 2 operates in order to provide adequate volumetric flow for a given application at a given speed. The starting point for choosing the vane 2 dimensions is in deciding on an acceptable average tip speed for a seal (the seal glands 10 are shown) on the tip (distal end) of the vane 2. The tip speed considerations are different if the tip seals are of the contacting, or clearance, type. The tip speed in conjunction with the vane 2 oscillating frequency and magnitude of angular motion through which the vane 2 oscillates determines the maximal radius of the distal end of the vane 2. Once this is determined, the length of the vane 2 is chosen so as to provide the necessary chamber volume.
Once the overall size of the vane 2 has been determined, a material is chosen that is compatible with the application in terms of strength, temperature, corrosion resistance, longevity, and cost. The combination of size and material choice dictates the mass of the vane 2 which in part determines the inertia.
It is now up to the drive mechanism to link a source of input power, in the case of a compressor, directly to the oscillating vanes 2. Given that the inertial and pressure loads have already been previously determined, decisions regarding material choices and drive mechanism configuration are made in order to reduce the associated loads on the components of the OVM to acceptable limits.
One of the most influential discoveries that has been made that lowers the loads on the drive mechanism is to invert the OVM so that its oscillating vanes 2 no longer pivot closely clustered in a group located towards the middle of the machine and to allow the vanes 2 to pivot at the periphery of the machine where they are at a greater distance from the center of rotation of the drive mechanism. This change in configuration provides additional room for stronger drive components while preserving the original compactness desirable of the OVM concept.
The present invention also differs from the OVMs previously described by Chomyszak in that, due to the novel configuration, they can be built with a drive mechanism on either or both ends, or faces, of the machine. Therefore, some vanes 2 may be driven by one drive mechanism and other vanes may be driven by a second drive mechanism. The drive mechanism may be of the same type or may be different driving mechanisms. Hence a common shaft may be tooled to be driven from both ends. This effectively distributes the driving load and allows additional space for stronger drive mechanism components if necessary.
A second advantage of inverting the vane pivots 7 to the periphery of the machine is that it also presents the end walls of each chamber 16 towards the periphery as well. This facilitates a much more direct routing of gases into and out of the chamber 16 via the ports and valves 18 located in the end walls of each chamber 16. It also better facilitates the assembly, maintenance, and repair of valving devices used on the OVM by locating those valving devices external to the machine where their accessibility is greatly improved.
Referring now to the drawings wherein the views are for purposes of illustrating preferred and alternate embodiments of the invention only and not for purposes of limiting same. While the oscillating vane machine is designed for and will hereinafter be described as either a compressor or an expander, it will be appreciated that the overall inventive concept involved could be adapted for use in many other machine environments as well, such as engines and pumps.
Pivoted vanes 2 of the present invention are manufactured to maximize the allowable torque along the vane shaft 7. This is accomplished by employing an integrated vane 2 and shaft 7 configuration. For structural purposes it is better to have the vane 2 and the shaft 7 be made from one piece. This is useful when combating increasing loads due to inertia and/or pressure differential.
In this embodiment which is shown in
While only two fastener 12 holes in each end cap 11 are shown in the figure, more or less fasteners 12 can be used depending on other design considerations. In addition, although not shown in the figure, it may also be desirable to machine in registration features in the back of each endcap 11 and on both ends of the vane 2 body. In this way “registration” could be used to provide alignment of the endcaps 11 to the vane 2 body as well as to provide a means of mechanical sealing at those two joints. The registration could be any male/female combination of shapes or features as known to those skilled in the art.
The pivoted vane 2 assemblies of the present invention may also be manufactured to contain sealing glands 10. Such glands are shown in
The peripherally pivoted vanes 2 of the oscillating vane machine of the present invention can be chosen, selected or manufactured from a wide array of materials and can be dependent on application or the intended use of the machine. For example, at low pressure and low temperature, the peripherally pivoted vanes 2 may be manufactured from a plastic or plastic-like material. At high pressure and temperature, it may be desired to have peripherally pivoted vanes 2 manufactured from a stronger material such as a metal or ceramic. Therefore, according to the present invention, the peripherally pivoted vanes 2 may be manufactured from steel, aluminum, or any metal, plastic, ceramic, composite, polymer or the like. Furthermore, it may be advantageous to plate or overmold the peripherally pivoted vanes 2 with a layer, film or deposit of a second material. The plating or overmolding may comprise the same material as the peripherally pivoted vane 2 substrate or may be different in kind or amount. For example, a metal peripherally pivoted vane 2 may be plated or overmolded with a polymer or plastic to improve movement within the main chamber 16 by reducing friction. Overmolding can also be used to reduce the weight of the pivoted vane 2 which in turn reduces its inertia. Overmolding and plating may be done to all, or only selected, surfaces of the peripherally pivoted vanes 2.
The peripherally pivoted vanes 2 of the oscillating vane machine of the present invention may also be designed to undergo or withstand a certain degree of deformity. Generally, larger machines, (e.g., larger peripherally pivoted vanes 2), can withstand more deformity. It is understood in the art that one problem with oscillating vanes 2 is detrimental harmonics. It is therefore desired to design the vanes 2 of the present invention and the vane actuation system to avoid any detrimental harmonic events. This problem is addressed in the selection of materials, size and proportion of peripherally pivoted vanes 2 as well as the acceleration and deceleration profiles of the oscillating motion of the peripherally pivoted vanes 2 so that the magnitude of the peripherally pivoted vane resonance will be minimized and occur at a frequency higher than the frequency at which the peripherally pivoted vanes 2 will be operated thereby avoiding a detrimental harmonic contribution from the peripherally pivoted vane 2 or actuation system.
In one embodiment of the invention, the distal surface 13 of one or more of the plurality of peripherally pivoted vanes 2 lying parallel to the axis of the pivot 7 is a surface which is substantially flat, convex, concave, toroidal, slanted or any nonflat shape specifiable by a mathematical equation.
In another embodiment of the invention, the lateral surfaces 14 or side surfaces 15 of one or more of the plurality of peripherally pivoted vanes 2 is substantially flat, convex, concave, toroidal, slanted or any nonflat shape specifiable by a mathematical equation.
Furthermore, the peripherally pivoted vanes 2 of the oscillating vane machine of the present invention may be rotated about their pivots 7 at any desirable angle.
In
According to the present invention, when the pivoted vanes 2 are arranged peripherally, many configurations of chamber number and placement are possible.
In all cases, the chambers 16 are contained within a stator 1. The stator 1 can be of monolithic construction with a plurality of chambers 16 or it can be comprised of an assembly of sub-stators 1, each containing an individual chamber 16 or a subset of chambers 16. It is understood that because the vane 2 oscillates or pivots within a main chamber 16 that the first and second side vane surfaces 15 may be referred to as “leading” and “trailing” surfaces. These terms are relative to the direction the pivoted vane 2 is moving and therefore the naming of side vane surfaces 15 are interchangeable when discussing the direction the pivoted vane 2 is moving.
The OVM of the present invention may take any of several external shapes. This shape may be determined by the number of chambers 16 and optimal distancing of the chambers 16, one from the other. The external shape may also be independent of the number of vanes 2 or chambers 16 contained therein. For example, the maximum distance achievable between the vanes 2 of a three-vane machine would be in a triangular configuration. For a four-vane machine, it would be a square. In this embodiment however, the stator 1 may be configured in such a way as to optimize the porting faces of the machine or the sizing/shape of the machine for a particular use and may not be triangular even though the OVM contains three chambers 16 of peripherally pivoted vanes 2. In accordance with the present invention, the stator 1 containing the three-chamber OVM may be formed such that it presents a square, or other shaped external surface.
The present invention embraces OVMs which present any one of a rectangle (2-sided), triangular (3-sided), square (4-sided), pentagonal (5-sided), hexagonal (6-sided), heptagonal (7-sided), octagonal (8-sided), nonagonal (9-sided), decagonal (10-sided), and hendecagonal (11-sided) shape. It is further within the scope of the invention for the OVM to comprise any of 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 chambers 16.
The oscillating vane machines of the present invention, irrespective of chamber number or overall size may be driven by any of several drive mechanisms or systems. These include, but are not limited to, a master/slave radial drive mechanism 54, a crank slider mechanism 27, a gear driven crank rocker drive mechanism 28 and a scotch yoke mechanism 29. In addition, the OVMs of the present invention may be driven from either face, or end, of the OVM.
While each master connecting rod 4 and slave connecting rod 5 has not been labeled, one of skill in the art will appreciate that this type of drive mechanism has to have a master connecting rod 4 to which the slave connecting rods 5 are attached.
Other drive mechanisms which may be employed, include, but are not limited to, rack and pinion system, a cam and camshaft, a rod and crankshaft, a desmodromic drive system, a cam with one or more springs, a cam and rod, reciprocating gears attached to the pivots, a dual cam with pins, a dual cam with gears, a tangential torqing device.
According to the present invention, novel porting configurations have been discovered which significantly improve the gas management within an oscillating vane machine. The gas dynamics in the inlet and discharge manifolds are also adversely affected by fully phased motion creating pulsation effects which induces vibration in the piping system (breaking pipes) and negatively affects the operation of the inlet and discharge valves 18.
In studies of the machine dynamics and flow in the OVM of the present invention, applicants noted that if the pivoted vanes 2 are actuated in a phased or synchronous manner, the torque spikes created by all vanes 2 experiencing the same phased acceleration and loading profiles requires an extremely large flywheel to dampen out the torque spikes. This is problematic as far as the size of the drive mechanism components necessary to handle these torque spikes as well as the weight of the flywheel needed to dampen out said torque spikes.
To circumvent this problem means that a practical implementation of a multi-vane oscillating vane 2 machine should have the vanes 2 moving out of phase. This reduces the torque spikes as well as the pulsation effects. As used herein the term “de-phased” means that the compression or expansion stages of the vanes 2 are not completely synchronous relative to each other. It is therefore desirable to have as many vanes 2 de-phased, one from another, as the drive mechanism will allow. This is in contrast to the self balanced, synchronized motion of the vanes 2 of Chomyszak (U.S. Provisional Application Nos. 60/889,315 filed on Feb. 12, 2007 and 60/846,543 filed on Sep. 22, 2006) which were at all times in phase.
Another advantage of de-phasing is to confuse the harmonics of the machine such that any unwanted frequencies are not excited or enhanced. It will be understood by those of skill in the art, armed with the present disclosure, that selection of an appropriate number of vanes 2 (including materials selection for their manufacture) and drive mechanism can result in optimized pulsation harmonics and reduced torque spikes. For example, single vane 2 machines would be expected to resonate at only one frequency making tuning difficult. However, as the number of vanes 2 increases so do the nature and strength of harmonics that must be managed. In the present invention, the more vanes 2 utilized, the more freedom of harmonic tuning is afforded in the design for any particular application.
Consequently, the OVM, including applications which incorporate rotary valves 43 are more immune to pulsation problems. In fact, much effort has been expended in the art to provide surge bottles to dampen out pulsations in reciprocating piston compressors.
Of the drive mechanisms 54 disclosed herein, three allow de-phasing of the vane 2 motion: master/slave radial drive 54, crank rocker 28 (with gears), and crank slider 27 (with gears). Drive mechanisms which de-phase the vane 2 motion will require additional features necessary to balance the mechanical vibrations caused by de-phasing the vanes 2. The driven mechanisms can be mechanical or electrically powered.
According to the present invention, improvements in porting of the OVMs are disclosed. It was discovered that during the discharge event there would be a very large pressure rise in the end of the chamber 16 furthest away from the discharge port 9. This pressure rise consumes excess energy and increases localized loads on the vanes 2, neither of which are desirable. When the discharge port 9 was relocated to the center of the machine the pressure rise significantly decreased. This can be explained as follows. When the gas from the chamber 16 is being pushed through the discharge port 9, it is traveling in a plane that is parallel to the side wall 15 of the vane 2 and the port 9 at first, but then it needs to turn 90 degrees in order to flow out of the port 9. When the discharge port 9 is located close to the end of the chamber, the ability of the gas to ‘turn the corner’ is impeded. When the discharge port 9 is located in the center, the gas approaches the port 9 from both directions, and when those two gas flows meet each other, they act to ‘turn the corner’ much more efficiently thereby reducing the pressure rise in the chamber 16 during the discharge process.
The valves 18 of the oscillating vane machine of the present invention may be in fluid communication with the atmosphere, each other or other devices.
The valving system of the present invention may also be configured to contain piping to connect the valves 18 into the plenum of the machine; this being similar to a feed/collection system for gas management.
Valves 18 useful in the present invention include stationary, rotary, hinged, poppet, reed (or high frequency valve), plate, channel, flapper and the like. The valves 18 of the machine may also be arrayed linearly or in preselected patterns.
Air compressors are used in a large variety of applications. In most cases, the application has varying demands for the compressor output capacity (CFM) and pressure (psi). In order to meet these varying demands, compressors employ a variety of means to control the operating characteristics in order to match the demand. It is within the scope of this invention to provide a new and unique means of effectively varying the inlet conditions to the compressor so that its output capacity is controlled as well as improving its overall adiabatic efficiency utilizing a Dragonfly Rotary Inlet Valve (DRIV) as disclosed herein.
To this end, the present invention also provides a novel method of controlling the output capacity of a positive displacement compressor, particularly an oscillating vane compressor, wherein a rotating valve 43 allows outside air to communicate with the compression cavity via passages formed on the periphery of the valve 43. Also provided is a novel method of improving the overall adiabatic efficiency of a positive displacement compressor, particularly an oscillating vane compressor, by optimizing its internal compression ratio. In this embodiment, a seal system is formed around the inlet and outlet passages of the valve 43 to prevent leakage of the compressed air and reduce the radial load applied to the valve 43. A bearing affixed to the one end of the rotating valve 43 helps to support the radial loads. A motor 41 directly mounted to the valve 43 at the other end to help support the radial load and provide the rotational motion to control the location of said valve 43 in relation to the compressor crank angle. A motor controller 47 connected to the motor 41 which reads the compressor crank angle and the demand signal and provides an appropriate output signal to the motor 41 to locate the valve 43 in the desired position based on a set of pre-programmed algorithms.
Referring now to
In
According to the present invention, the rotating valve 43 is rotated by the servo motor 41 in a controlled motion with respect to the compressor crank shaft 48. By varying the motion of the rotating valve 43 in relation to the vane 2 position, the inlet conditions can be changed to restrict the inlet flow of air to the compressor. Controlling the duration of time the valve 43 is “open” varies the inlet conditions and thus the output of the compressor.
Controlling the timing of the opening of the valve 43 in relation to the vane 2 position affects the capacity of the compressor. An algorithm which controls the opening duration and timing with respect to the vane 2 position may be used to determine the output of the compressor. Pluralities of algorithms stored in the controller (C1) for a plurality of varying compressor operating conditions determine the output of the OVM compressor for each condition.
In another embodiment, a unique seal system has been developed for the Dragonfly Rotary Inlet Valve (DRIV) which reduces the leakage in or out of the compressor during its operation. This embodiment is shown in
The radial wiper seals 42 are oriented axially with the valve 43 preventing radial leakage of the compressed air. The separating distance between the seals 42 is optimized to control the area affected by the pressure thus reducing the radial load on the rotating valve 43.
The close coupling of the servo motor 41 to the rotating valve 43 is a unique feature which eliminates the need of an elastomeric coupling or other coupling device thus reducing the system inertia and the motor torque requirements.
Another novel application of the DRIV is its ability to be used as a discharge control valve by mounting it at the discharge connection of the OVM compressor. In this application, the rotary valve 43 controls the internal compression ratio of the compressor. The valve 43 rotation is controlled similarly as the inlet valve above with the main difference being changes to the motion control algorithm. In this application, the algorithms would be modified to allow the valve to open sooner than the compressor's peak compression ratio thus reducing the internal pressure to better match that of the demand.
In addition, multiple rotating valves 43 (DRIVs) can be mounted to a common servo motor shaft. This embodiment is shown in
Likewise, the same combination valve 49 can be used as a discharge valve connected to the same compression chambers as the inlet valve but at some distance down the axis of the vane 2. This combination discharge valve 49 can help improve the compressor's overall adiabatic efficiency by utilizing a similar motion control algorithm as the single discharge valve described above.
The Dragonfly Rotary Inlet Valve (DRIV) of the present invention may be an integral part of a larger compressed air system, working in unison, to control the output quantity of air from the OVM of the present invention. A schematic of the compressor system is shown in
In another embodiment, the OVMs of the present invention may be driven by a crank slider with linkage drive mechanism 53. This driver is shown in
In this embodiment, the crankshaft 34 and connecting rod 33 drive the slider 30 in a reciprocating motion guided by a linear guide 52. As the slider moves to and fro, the linkages 31 attached to both the slider 30 and the vane lever arms 3 rotate the vanes 2 in an oscillating fashion. This embodiment would be best suited to drive a 4-vaned OVM. However, it could be adapted to drive OVMs with more or less vanes 2. It is preferred, but not required, that an OVM having an even number of vanes 2 employ this drive mechanism so that the lateral loads imposed on the slider 30 and its linear guide 52 would be minimized. This drive mechanism does not allow for de-phasing.
According to the present invention, all rubbing or contacting surfaces between the peripherally pivoted vanes 2 and the housing, stator 1 or main chambers 16, are designed to ensure minimal frictional losses. As such, materials used for manufacturing the machine and for surface coatings or treatments should be carefully matched. Optimization of sealing conditions and selection of sealing materials or lubricants is within the skill of the art. Furthermore, when the relevant housing or stator 1 components and the vane 2 are made from low expansion, low friction materials, such as ceramics, it may be practicable to dispense with lubrication altogether.
According to the present invention, seals are formed between the peripherally pivoted vanes 2 and the lateral 14 and distal 13 surfaces of the chambers. In addition, the pivots 7 of each vane 2 may form a conformal seal with the stator 1 or housing.
In one embodiment the peripherally pivoted vanes 2 are configured with balanced seals. Balanced seals allow for higher operational speeds without the manifestation of a deforming centrifugal force resulting on the distal vane surface 13 or the lateral vane surface 14 as is seen with sliding vane machines of the art.
The seals used may comprise any sealing material including metals, composites, plastics, rubber, Teflon, and the like.
The oscillating vane machine of the present invention is useful as a compressor. As such, the compression achieved by the machine may be substantial in any chamber, and even more when multi-staged.
In another embodiment, the oscillating vane machine of the present invention operates as an expander. As such, inlet ports 8 act to allow sufficient compressed fluid to enter the chamber then allow the compressed fluid to drive the vanes, extracting work until final exhaust at a pressure equivalent to that desired at the discharge port 9. With suitable control algorithms, the aforementioned servo controlled rotary valve system could be implemented to provide the necessary valve control required by the OVM of the present invention to act as an efficient expander.
Multi-staging of the machine of the invention can be accomplished in 2, 3, 4 or more stages and may further comprise an intercooler or intercoolers. During multi-staging, not all of the chambers 16 need be at the same pressure.
In this way, multi-staging increases the efficiency of the machine as it reduces the energy necessary to compress the fluid or gas.
The present invention is also amenable to applications of variable pressure ratio multi-staging. In this application, the chambers 16 can be dynamically reassigned to improve performance particularly at high pressure ratios like those used in compressed air storage facilities.
It may also be necessary to incorporate a cooling system into the oscillating vane machine of the present invention. Coolants useful in such as system include water, oil, a refrigerant or the like. Additionally, the coolant may act as a lubricant.
The present invention has applications in power supply configurations (either functioning as a compressor or expander) which exploit natural resources such as solar, geothermal and wind power.
The OVM of the present invention finds uses as either a compressor or expander or in some instances where multiple machines are used in a single application, as both. The OVM of the present invention may operate to expand or compress any number of working fluids. As used herein the term “working fluid” includes any substance acting as a fluid as that term is used in the art. Working fluids may comprise air, water (including all phases of water), multiphase hydrocarbons, fuels, flowable gases, compressible gases, mixtures and the like.
In these uses it is expected that the market entry device could take many forms. These include, but are not limited to single compressor or expander systems as well as multi-component arrays. The power rating on these systems may vary and includes systems having a capacity of 1-5 MW, 5-10 MW, 10-50 MW, 10-20 kW, 20-40 MW, 5-10 kW, 20-50 kW, 50-100 kW, 500-100 kW or 100-500 kW.
The OVM of the present invention has many applications. Broadly, the OVM of the present invention may also be used in compression, power generation, as well as power recovery. The OVM of the present invention finds use in many commercial process applications, including in the automotive industry, refrigeration, applications and the like detailed herein.
It will be understood that applications recited herein are not exhaustive and not meant to be limited solely as categorized. As such, any one or more uses of the OVM of the present invention, as either a compressor or expander, as single or multi-stage, may be combined to address the particular problem.
When used as a compressor, the invention may derive motive power or force from many sources including natural and artificial inputs. Natural motive forces include, but are not limited to wind, wave, ocean and river current, solar and geothermal. Artificial motive forces or those which are man-made or deriving from man-made technology include, but are not limited to heat engines and electrical motors.
The compressed fluid may be expanded immediately for the generation of power or other useful products, or may be stored for later expansion.
When used as an expander the invention may derive motive power or force from compressed and/or heated fluids, translating such force of pressure into mechanical or electrical power. The invention may also expand such compressed fluids directly into useful products such as isolated gases or liquefied air.
Wind
In one embodiment, the OVM of the present invention is useful in wind-driven applications. As used herein, the term “wind-driven applications” include those applications or uses of the OVM of the present invention as either a compressor or expander or both in a process, device or method which captures, harnesses or otherwise exploits wind, wind power or wind energy.
As a motive force, wind can be harnessed, in conjunction with the OVM of the present invention in improvements in compression and storage of compressed gas, as well as in the compression of gasses or fluids for storage and electricity generation.
In one embodiment, the motive force of the wind may be exploited using the OVM of the present invention in technologies involving mechanical vapor recompression (MVR).
In one embodiment, the OVM of the present invention employing wind as a motive force may act as a compressor to produce liquid air or liquid air products, and compress carbon dioxide for sequestration.
Wave
As a motive force, waves can be harnessed, in conjunction with the OVM of the present invention in improvements in compression and storage of compressed gas, as well as in the compression of gases or fluids for storage and electricity generation. In one embodiment, the motive force of waves may be exploited using the OVM of the present invention in technologies involving mechanical vapor recompression (MVR).
In one embodiment, the OVM of the present invention may be used in offshore applications.
In one embodiment, the OVM of the present invention employing wave as a motive force may act as a compressor to produce liquid air or liquid air products, and compress carbon dioxide for sequestration.
Ocean Current
Further, the OVM of the present invention may be integrated into ocean or river current technology for electricity generation as well as for offshore maritime or marine applications for power or electricity generation.
Distributed CAES
Further, the OVM of the present invention may also be harnessed or exploited in the use of distributed Compressed Air Energy Storage (CAES) systems. This application also finds uses in electricity generation and storage. In one embodiment, the generation and/or storage may be at the customer side or end of the meter.
When used as an expander, the OVM of the present invention may be powered by any number of heat sources, natural or artificial. For example, when a process or method employs the use of steam or vapor, the heat necessary to generate the steam or vapor may come from any number or sources. Heat sources include, but are not limited to solar, geothermal, radioactive (nuclear) and chemical. Also included are exhausts from other processes and the combustion of fuel, including waste heat and intentional heat.
In many processes of energy production, much energy is lost to the system and surroundings as heat. Waste heat recovery therefore represents an attractive avenue for improving and optimizing any heat-generating system. For example, engines represent a major class of prime movers in society. These prime movers generate a great deal of waste heat that, if captured and exploited, could reduce the overall cost of systems using them. Waste heat recovery may also be effected from incineration, anaerobic digestion, composting, radioactive, mechanical biological treatments, recycling plants and processes, sewerage, biogas recovery, landfill gas recovery, biomass gasification. Industrial processes which could benefit from incorporation of the machine of the present invention include, for example, aluminum smelting, metal casting, steel processing, glass making and chemical processing including manufacture or processing of fertilizers or in the production or refining of hydrocarbon fuels including gasoline.
To this end, the OVM of the present invention may be used to capture waste heat from engines in many processes.
Applications of the OVM of the present invention include, bottoming cycle expanders for power recovery from waste heat of diesel/gas powered engines including microturbines, backpressure steam expanders for power recovery from district heating/distributed steam pressure reduction), boiler cogeneration expanders and micro cogeneration expanders for recovery of power from waste heat, and as chiller expanders for the recovery of power from expansion of refrigerant. In all these cases the recovered mechanical power may be used directly or to drive a generator to produce electricity.
As used herein a “GenSet” is any distributed generator system or electrical generator such as a diesel, natural gas, or gasoline powered generator located in proximity to the end-user rather than in a central location such as those utilized by commercial power providers. A genset can be utilized as an augmentation to an existing electrical grid system or as an “off-grid” power source depending upon the needs of the user. Gensets are often used by hospitals and other industries which rely upon a steady source of power, as well as in rural areas where there is no access to commercially generated (‘grid’) electricity.
The OVM of the present invention may also be used in conjunction with gas pipelines for electricity generation (e.g., power recovery from reduction of transmission to distribution pressure) and in microturbine combined cycles (e.g., power recovery from waste heat of microturbine fuel combustion).
The OVM of the present invention also finds utility in several processes including, but not limited to process compression and process expansion of working fluids.
In one embodiment the OVM of the present invention may be used in air compression applications such as in pneumatics for tools or machinery. In some embodiments the compressor may be coolant injected or water injected.
In one embodiment the OVM of the present invention may be used in natural gas compression, gas field/wellhead compression into collection system or compression to transmission pipeline pressure.
As an expander the OVM of the present invention may be employed in natural gas regasification and for removal of contaminants from natural gas.
Process Compression
Within the field of process compression the OVM of the present invention may be exploited in chemical processes such as separation processes including air and constituent gas separation. These processes may include the separation of hydrocarbon gases and related gas separations as well as petrochemical refining. In these processes a compressed gas is cooled causing constituents such as long chain hydrocarbons (greater than 3 carbons) to drop out of the mixture. It is also possible to recover power from this expansion process.
In one embodiment steam or vapor upgrade or evaporation enhancement can be accomplished using the compressor of the present invention. For example, a compression cycle may be used to create steam or vapor at a higher pressure from steam at a lower pressure instead of making the higher pressure steam from ambient working fluids.
In one embodiment, the OVM of the present invention can be used in the food processing industry.
Refrigeration/HVAC/Air Cycles
The OVM of the present invention may be employed in any number of compression or expansion processes within devices involving air cycles. In this manner, the present invention may be used for compressing refrigerants in heat pumps, chillers and in refrigeration cycles. It may also be used for compressing refrigerants that are condensing as well as gas cycle refrigerants. In addition to conventional refrigerants the compressor may employ as a working fluid natural refrigerants such as carbon dioxide (CO2), air and ammonia.
Devices which may be configured or manufactured to utilize the OVM of the present invention include, but are not limited to, air separation units (ASUs), air conditioning systems, packaged condensing units (e.g., air conditioning units located on the roofs of commercial buildings) and splits (e.g., medium sized air conditioners). In one embodiment the OVM of the present invention may be used in integrated chillers/refrigeration units (window air conditioners) or in stand-alone air conditioners. The devices may be further intercooled. Technological application of cryogenics may also utilize the present invention.
Distillation/MVR (Mechanical Vapor Recompression)
In one embodiment, the OVM of the present invention may be applied in the field of distillation or mechanical vapor recompression (including for distillation). Irrespective of motive force, the machine of the present invention may be used to facilitate these processes.
To this end, the OVM of the present invention may be used in the process of petroleum processing, distillation of ethanol or other alcohols or alcohol-containing liquids, water purification and constituent or waste separation/concentration.
CO2 Compression/Sequestration
The OVM of the present invention may be used in the separation/sequestration of CO2 as, for example, in the process of enhancing oil recovery. It may also be used in the compression of gases originating from flue gas separations or flue gas processes.
The machine of the present invention may be used in many aspects of the automotive industry. As used herein “automotive” embraces on-road and off-road vehicles including military, construction, mining and farm vehicles. Also included are aircraft and marine vehicles and applications therein.
To this end, the OVM of the present invention may be used as an automotive supercharger or as the compressor or heat pump in an automotive air conditioning system. It may also be integrated into automotive exhaust systems (potentially replacing conventional blowers) or used for air braking. It may also be for bottoming cycle power (waste heat) recovery as an alternative to turbo-compounding. Further, the OVM of the present invention may be used in hybrid air accumulation (supercharger) such as those in hybrid vehicles.
In addition, the OVM of the present invention may be used in fuel cells, vacuum pumps, liquid pumps, heat pumps and for any application requiring a compressor or expander in solar heat power generation.
Incorporation into Compressed Air Energy Storage (CAES) Systems and Devices
The OVM of the present invention may also be used by electricity consumers to relieve them of high charges for energy and power demand from load serving entities (LSE) with use of compressed air energy storage (CAES) systems that do not need but may use combustion to provide power for peak use on the customer side of the meter, creating a new method of doing business that makes development of CAES systems that are economically viable.
Our invention focuses on using a CAES system on the customer side of the meter without combustion and integrated into the energy management program (EMP) of the facility, so that end users can reduce their costs. The system can be run manually or connected into a building Energy Management System (EMS) that manages the extraction of energy from the CAES system to reduce costs. It can be remotely monitored by associates of the end user (headquarter, consultants, suppliers or renters of the CAES system) to assure performance and reduction in energy costs. The system should preferably comprise panels equipped with switchgear that would allow power to flow from the grid into the end user's facilities, from the CAES system into the end user's facilities, and, optionally, from the CAES system to the grid. Power extracted from the CAES system during periods of peak use or high rates will enable the end user to reduce the power purchased from the grid, with a reduction in the kW or demand charge during the period of peak uses or higher rates.
The voltage from the CAES system would most likely be the same voltage as the end user needs, so that if the power is sold back to the grid it would go through the transformers, if any, before entering the grid.
The system can also be integrated with equipment that captures and uses the cooling capacity of the CAES system that develops when the compressed air is expanded.
In one embodiment the CAES system is built on the customer side of the meter (i.e., “on-site”). This system consists of an OVM compressor that compresses a fluid, such as air, into storage container that is, optionally, buried in the ground. The container is capable of withstanding high pressures. An OVM expander expands the compressed air when power is needed, usually during the period of peak power demand as indicated on the clock. The OVM compressor and expander could be the same device or separate devices. The OVM compressor is operably linked to at least one power source, such as utility supplied electricity sourced from the utility side of the meter. Alternatively, the power source can be a solar panel. In a particularly preferred embodiment, the power source is not a combustion engine. The OVM expander converts the energy stored as compressed air into mechanical power. This mechanical power may be used directly or to drive a generator, which converts the mechanical power into electricity. Power is then provided to the customer's facilities, using a generator that is part of the designed system to do so, preferably using low voltage suitable for the host facility. Cooling can also be extracted from the expanding air stream and cools water in the water stream via heat exchanger. The water is either used immediately for cooling or is stored for later use. This displaces the demand for power for air conditioning, especially at peak temperatures and demand.
While a single storage container, compressor and expander can be used, a plurality of storage tanks, compressors, and/or expanders may be used in order to assure redundancy, reliability, availability and to avoid demand charges for equipment failure.
The storage containers can be accessed in series or in parallel, and can be the same or different sizes. The containers can optionally be insulated to reduce heat loss or not insulated to facilitate heat loss.
The compressed fluid (e.g., air) can be stored in an underground void (such as a cave or mine), although it will often be preferable to store in a tank above or preferably below ground. In one embodiment, the tank is mobile (e.g., a truck). The container is preferably designed to withstand a variety of possible pressures. The size of the container and the pressures that it is designed to withstand are related to the energy capacity of the system. Where size of the container is a limiting design factor, the container can be designed to withstand 100 atmospheres or more.
The storage container and, optionally, other components of the on-site CAES systems could be buried deep enough to be attack-proof or resistant.
The invention relates to a supercharger for an internal combustion engine. In a preferred embodiment, the invention comprises an internal combustion engine comprising a combustor (such as one or more cylinders, each cylinder providing a combustion chamber and one or more fuel injectors in communication with said cylinder(s), capable of injecting fuel into each said combustion chamber); an air intake line operatively connected to the cylinder(s) and to an OVM compressor, to provide compressed air to the combustion chamber(s) from the compressor; an exhaust line also operatively connected to the cylinder(s), to receive exhaust gas from the combustion chamber(s); and a main crank shaft functionally attached to and driven by said cylinder(s).
Air is provided to the OVM compressor via an intake line. The air can be fresh air or re-circulated air, as can be provided from crankcase gas or exhaust, or some combination thereof. Further, the air can be provided at atmospheric pressure or compressed (e.g. via an OVMC) and at ambient temperature, heated (as can occur upon compression) or cooled (e.g., via a heat exchanger or regenerator). The system of the invention can further comprise, in addition or as an alternative to the OVM compressor, an OVM expander operatively connected to exhaust line.
In a particularly preferred embodiment, at least a portion of the exhaust gas from the combustor is directly or indirectly (e.g., via the expander) directed to the air intake line of the system. This can be accomplished by, for example, directing a recirculation line of a portion of said exhaust gas to said air intake line. An EGR control valve operated so as to control the concentration of re-circulated exhaust gas and air can be advantageously added. Typically, between 10 and 30% of the total intake gas directed into the OVM compressor is recirculated exhaust gas.
In yet another embodiment, exhaust gas can be direct to the OVM compressor prior to mixing with the intake air via a line. In this embodiment, one or more chambers of the OVM can be dedicated to compressing exhaust gas independently of compressing air. The compressed exhaust gas and air can be subsequently mixed for combustion. Thus, by way of example, one or more chambers can compress exhaust while the remaining chambers can compress air. This embodiment provides an alternative method for controlling recirculation.
The system can include a controller (e.g., a computer) that controls at least one of: the quantity of fuel injected, the quantity of recirculated exhaust gas, the quantity of air, the pressure of recirculated exhaust gas, and/or the pressure of air.
In yet another embodiment, crankcase gas can be removed from the combustor and recirculated via the intake air line. This gas can be advantageously pumped via an OVMC, as described herein. Combinations of multiple OVMs providing a single device that manages multiple (or all) gas flow within the engine or system are possible.
Alternatively embodiments of the invention include by-pass valves that permit avoiding supercharging the intake gas when it is unnecessary.
The OVM of the present invention may be used as a component of one or an array of buoys that are connected to form a wave energy extraction system. The OVMs of the present invention may be employed in a manner to act as either a compressor or expander for use in the extraction of energy from heave and surge and subsequent transmission, storage, and conversion to electricity.
In one embodiment, the compressed air may act as a working fluid within a non-combustion power cycle such as those disclosed in copending patent application Ser. No. 60/860,163 by Ingersoll, Attorney Docket Number 4004.3022US filed Nov. 20, 2006, the contents of which are incorporated herein in their entirety.
It is an object of this invention to provide a fluid compressor comprising: a wind turbine (including, but not limited to a Horizontal Axis Wind Turbine or a Vertical Axis Wind Turbine, or Arrays or Clusters grouped together in multiples of said wind turbines); an oscillating vane machine compressor (OVMC) characterized by a fluid intake opening and a fluid exhaust opening, wherein the wind turbine drives the OVM compressor. The combination of the OVMC and wind turbine along with facility for storage of the compressed fluid permits excellent control over the time of electrical power generation, thereby maximizing the commercial opportunity and meeting the public need during hours of high usage. Additionally, the invention in certain embodiments avoids the need to place an electrical generator off-shore. Additionally, the invention allows for the production of other products than electricity, such as mechanical power when desired. Further, the apparatuses of the invention can be operated with good to excellent efficiency rates.
The wind turbine is powered by air flow such as is created by wind. In this embodiment, the turbine can be a windmill, such as those well known in the art. One example of a windmill is found in U.S. Pat. No. 6,270,308, which is incorporated herein by reference. Because wind velocities are particularly reliable off shore, the windmill can be configured to stand or float off shore, as is known in the art.
The invention further relates to the use of an OVM to store and release energy in the form of a compressed gas or fluid, such as air. In such an embodiment, the turbine can be replaced with another power source that drives the OVM.
Further, the sizes, capacities, of the OVMCs and OVMEs can be approximately the same or different. Additional modifications to further improve energy usage can be envisioned from the apparatus of the invention. Energy recycle streams and strategies can be easily incorporated into the apparatus. For example, the expanded fluid exiting from the expander will, in the absence of heat addition, generally be cold. This fluid can be efficiently used as a coolant, such as in a heat exchanger to provide refrigeration, air-conditioning or coolant for a condensing process. Likewise, the compressed fluid exiting from the compressor, or the cooling liquid, such as from the intercoolers, may be used to provide useful heat to a process.
The OVM compressor and OVM expander can be controlled to control the temperature or energy level of the fluids or gases, such as by controlling the rate, pressure, etc. Alternatively multiple sources of fluid (e.g., at different temperatures) can be used to control the temperature of the fluid at various stages of the process. The process can also be controlled by varying the pressure ratio of the compressor and/or expander to allow for optimal injection pressure into the receiver in relation to the pressure of the stored air.
In one embodiment, the apparatus comprises one, two or more oscillating vane machine (OVM) compressors. The compressors can be configured in series or in parallel and/or can each be single stage or multistage compressors. The OVM compressor will generally compress air; however, other environments or applications may allow other compressible fluids to be used. Examples of other compressible fluids include hydrogen, biogas, methane, natural gas (as may be found in a gas pipeline), propane, nitrogen, ethanol, carbon monoxide, carbon dioxide, argon, helium, oxygen, fluorocarbons, acetylene, nitrous oxide, neon, krypton, xenon, and the like.
The turbine is generally configured to power the OVM compressor(s). For example, the turbine can drive the OVM compressor via gearbox or directly by a shaft or directly to a draft shaft or gear of the compressor, or through a hydraulic drive.
Additionally, the invention can provide a method or means of controlling or allowing a turbine to drive the generator, the OVM compressor, or both (e.g., simultaneously). In a typical prior art apparatus, the variability of the torque of the turbine is undesirable. Where the turbine is driving the generator and OVM compressor, simultaneously, the apparatus can be configured and controlled to ensure that the torque to the generator is constant or fixed and the flux is controlled or modulated by the OVM compressor. Thus, variable flow can be used to modulate torque of the turbine allowing the generator output to be more constant.
Additionally or alternatively, the invention may include a means or method of control enabling a turbine and/or the OVM expander to drive the generator and/or OVM compressor. In this embodiment, the expander can complement the power input of the turbine.
In yet another embodiment, the generator (or other external power source) can drive the OVM compressor. This can be desirable to replenish the power storage within the conduit using off-peak power for use during peak power times, even when the turbine's activity is insufficient to do so.
In another embodiment, the oscillating vane machine compressor/expander (OVMC/E) can also be configured so that it can function as a compressor during the storage phase of the cycle and an expander during the power production phase.
The air exiting the compressor through the compressor exhaust opening will directly or indirectly fill a conduit. Multiple turbines, and their associated compressors, can fill the same or different conduits. For example, a single conduit can receive the compressed air from an entire windmill farm, wind plant or wind power facility. Alternatively or additionally, the “windmill farm” or, the turbines therein, can fill multiple conduits. The conduit(s) can be used to collect, store, and/or transmit the compressed fluid, or air. Depending upon the volume of the conduit, large volumes of compressed air can be stored and transmitted. The conduit can direct the air flow to a storage vessel or tank or directly to the expander. The conduit is preferably made of a material that can withstand high pressures, such as those generated by the compressors. Further, the conduit should be manufactured out of a material appropriate to withstand the environmental stresses. For example, where the windmill is located off shore, the conduit should be made of a material that will withstand seawater, such as pipelines that are used in the natural gas industry.
The location of the conduit can be under the ground or ocean surface or on the surface of the ground or an integral part of the wind turbine tower (e.g., a supporting member or nacelle).
The air (fluid) feeding the OVM compressor can be cooled in a slip, or side, stream off the conduit or in a storage vessel or tank. The air (fluid) feeding the OVM expander can be heated. Heating the fluid can have the advantage of increasing the energy stored within the fluid. The compressed air can be subjected to constant volume and/or constant pressure heating. The sources of heating/cooling can include thermal energy available in the oceans, rivers, ponds, lakes, underground and shallow or deep geothermal heating (as can be found in hot springs) or in the combustion of fuels. The conduit, or compressed air, can be passed through a heat exchanger to cool waste heat, such as can be found in power plant streams and effluents and industrial process streams and effluents (e.g., liquid and gas waste streams).
In one embodiment, is a method of storing and transporting wind generated power, comprising determining a site where wind speeds are sufficient for generating wind power that is remote from a user; providing one or more wind turbine stations for generating energy located at said first site; providing at least one OVM compressor per dedicated wind turbine associated with said one or more wind turbine stations; determining a planned route between said first site and a second site to be serviced by said wind turbine stations, (which includes, among other things, determining the approximate distance between said first and second sites; providing a pipeline structure along said planned route between said first and second sites for storing compressed air energy generated by said wind turbine stations; determining the pipe size and air pressure based on the amount of storage space that is needed within said pipeline structure, taking into account the approximate distance between said first and second sites; extending said pipeline structure from said first site to said second site along said planned route); providing at least one OVM expander located at or near said second site to allow said compressed air energy to be released; and providing an electrical generator to convert said compressed air energy released by said OVM expander into electrical energy. In this embodiment a first site may be located on a platform located in a body of water, with the pipeline structure extended down into the ground below the body of water, while the pipeline structure is extended to a second site located on land.
In one embodiment is provided a method of transporting wind generated energy, comprising determining a first site where wind speeds are sufficient for generating wind power that is remote from a user by providing one or more wind turbine stations for generating energy located a first site and providing at least one OVM compressor associated therewith; determining a planned route between said first site and a second site to be serviced by said wind turbine stations, wherein said planned route extends substantially along an existing path which comprises at least one taken from the following: an existing road, an existing easement, an existing conduit, an existing open access area, an existing abandoned pipeline; providing a pipeline along said planned route between said first and second sites for storing compressed air energy generated by said wind turbine stations and transporting the compressed air energy from said first site to said second site; providing at least one OVM expander to release said compressed air energy from the pipeline structure at or near said second site; providing an electrical generator to convert the compressed air energy released by said turbo expander into electrical energy; and providing said electrical energy to a user at said second site.
Further, in this embodiment, one OVM compressor may provided per dedicated wind turbine associated with said one or more wind turbine stations.
While the foregoing embodiments of the present invention have been described and characterized under various groups and headings, this organizational framework, including heading labels, is not intended to limit the scope of the present invention.
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
This application claims the benefit of U.S. provisional application No. 60/974,140 filed on Sep. 21, 2007. The contents of the above application is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60974140 | Sep 2007 | US |
