The present subject matter is related to devices for the production of heat, and more particularly, to methods and apparatus for generating heat using rotational energy.
A hydrodynamic heater generates heat by inducing shear within a fluid. The shear may come in the form of structure that is caused to move within the fluid. Heat may be generated by a principle known as fluid resistance heating, in affect, friction heating. Heating may also be generated by a principle of direct cavitation within layers of liquid. Although the transformation of mechanical energy into thermal energy via the hydrodynamic heater is relatively efficient, an increase in energy efficiency is desirable.
Like reference numbers generally indicate corresponding elements in the figures.
In the following description, embodiments of apparatus and methods will be disclosed. For purposes of explanation, specific numbers, materials, or configurations are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to those skilled in the art that the embodiments may be practiced without one or more of the specific details, or with other approaches, materials, components, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the embodiments. Accordingly, in some instances, features are omitted or simplified in order to not obscure the disclosed embodiments. Furthermore, it is understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of claimed subject matter. Thus, the appearances of the phrase “in one embodiment” or “an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in one or more embodiments.
Reference will now be made to embodiments illustrated in the drawings and specific language which will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Alterations and further modifications of the illustrated embodiments and further applications of the principles of the invention, as would normally occur to one skilled in the art to which the invention relates, are also within the scope of the invention.
The shaft 18 is operable to couple with an energy source operable for imparting rotation to the shaft 18 so as to rotate the rotation member 14 about the X-axis. Examples of a suitable energy source include, but are not limited to, an electric motor, hydraulic pump, and internal combustion engine using a drive shaft, power take-off, or belt drive, among others.
Referring again to
As the shaft 18 is rotated, the fluid driver elements 112 of the rotation member 14 move relative to the fluid interactive elements 12 of the stationary member 20. Fluid disposed between the fluid driver disk face 115 and the fluid interactive disk face 15 in the fluid interaction space 52 is acted upon hydrodynamically so as to induce heating therein. Fluid shear and friction causes the temperature of the working fluid to increase.
The hydrodynamic heater 2 also comprises a housing 30 defining a fluid cavity 32 into which the stationary member 20 and the rotation member 14 are disposed. The housing 30 defines a fluid inlet 34 and a fluid outlet 36 operable to provide fluid ingress and egress, respectively. The flow of working fluid is substantially from the fluid inlet 34, through the space between the fluid driver disk face 115 and the fluid interactive disk face 15 and out through the fluid outlet 36. The working fluid may be driven through the housing 30 by an external pump (not shown) in accordance with an embodiment or by the movement of the fluid driver elements 112 in accordance with another embodiment, but not limited thereto.
It is appreciated that the stationary member 20 may comprise one or more fluid interactive elements 12. The fluid interactive elements 12 are operable to cooperate with the one or more fluid driver elements 112 so as to induce fluid shear operable to heat the fluid therebetween. The fluid interactive elements 12 and the fluid driver elements 112, as provided in the embodiment of
One fluid driver element 112 may be sufficient to induce the necessary fluid movement to provide shearing that creates friction heating of the working fluid. It is appreciated that when reference is made to a plurality of fluid driver elements 112, it applies also to embodiments comprising one fluid driver element 112.
The amount of fluid shear, and thus the amount of heating of the fluid induced by the rotation of the fluid driver elements 112, is determined, at least in part, by one or more of the speed of rotation of the rotation member 14, the spacing X1 which is the distance of separation between the fluid driver disk face 115 and the fluid interactive disk face 15, and the speed of the working fluid into and out of the fluid inlet 34 and the fluid outlet 36, respectively. The properties of the working fluid also determine, at least in part, the degree of heat induced by the fluid movement. The properties of the fluid include, but are not limited to, density, viscosity, and heat capacity, among others.
It is appreciated that heat output of the hydrodynamic heater 2 may also depend on the size of the apparatus, such as, but not limited to the diameter of the fluid driver disk face 115 and the fluid interactive disk face 15. Also, and not limited thereto, the size and number of fluid driver elements 112 and fluid interactive elements 12 may also determine, at least in part, the heat output. Also, and not limited thereto, the number of rotation members 14 and stationary members 20 may also determine, at least in part, the heat output of the hydrodynamic heater 2.
The fluid inlet 34, the space between the fluid driver disk face 115 and the fluid interactive disk face 15, and the fluid outlet 36 define a fluid path (indicated by the arrows shown on
In accordance with an embodiment, an external fluid path 132 external to the housing 30 is established between the fluid outlet 36 and the fluid inlet 34 such that the fluid circulates from the fluid outlet 36, through the external fluid path 132, into the fluid inlet 34, and through the fluid cavity 32, as shown in
The external fluid path 132 may include a heat exchanger 72 or other suitable apparatus operable to exchange heat to a target environment as will be discussed below. Such target environment may include, but not limited to, a fluid path of a fan so as to heat air, such as a grain dryer, and heat hoses to heat and defrost frozen ground onto which the hose is placed.
The radial and axial placement of the fluid driver elements 112 and the fluid interactive elements 12 about the fluid driver disk face 115 and the fluid interactive disk face 15, respectively, as shown in
In accordance with the embodiment of
The rate of heat generation in the hydrodynamic heater 2 in accordance with embodiments depends, at least in part, on the hydrodynamic properties of the stationary member 20 and the rotation member 14 as well as the relative rotation speed between the two.
Therefore, for applications wherein a high rate of heat generation is desirable, it may be desirable that the rotation member 14 have a relatively high relative rotation speed with respect to the stationary member 20. The degree of fluid shear produced by the fluid driver elements 112 and the fluid interactive elements 12 is related to the relative rotation speed.
In addition, the maximum temperature that can be generated by a hydrodynamic heater 2 according to embodiments herein, depends, at least in part, on the heat capacity of the fluid 12.
The rotation member 14 comprises any material suitable for the particular purpose. Suitable materials include, but are not limited to, copper, aluminum, alloys of copper, alloys of aluminum, and other metallic or non-metallic materials.
Again referring to
Suitable working fluids for the particular purpose include, but are not limited to, liquid fluids such as water, propylene glycol, among others.
In accordance with another embodiment, fluid movement elements 38 are also operable to induce fluid shear in the working fluid. In yet other embodiments, fluid movement elements 38 in the form of fins disposed on the fluid interactive disk face 15 of the stationary member 20 induces fluid shear as the working fluid is driven past the fluid interactive disk face 15 by the rotation member 14.
In accordance with other embodiments, the working fluid is driven through the flow path by an external energy source, such as, but not limited to, a pump.
It is appreciated that the temperature to which working fluid passing through the fluid path 16 is heated depends, at least in part, on the rate of rotation of the rotation member 14 and the amount of fluid shear produced. Also, the temperature of the fluid depends, at least in part, on the rate at which the fluid moves through the fluid path 16, that is, on how long the fluid is undergoing fluid shear. Further, the temperature of the fluid depends, at least in part, on the efficiency of the fluid driver elements 112 and the fluid interactive elements 12 to produce fluid shear so as to induce heating of the fluid.
The performance parameters, such as, but not limited to, the rate of heat generation, rate of fluid flow, and fluid temperature, may be independent of one another as described in some embodiments herein. A hydrodynamic heater 2 in accordance with embodiments may be used to produce a specific temperature of working fluid in combination with a specific rate of fluid flow. Any two of the three parameters may be controlled independently of one another in accordance with at least some embodiments disclosed herein.
The energy source used to drive the rotation of the shaft 18 may comprise any suitable means. In accordance to embodiments, the shaft 18 may be operable to be coupled to a power take-off found on some motor vehicles, such as, but not limited to, many tractors, other agricultural vehicles, and heavy work vehicles. In such vehicles, some of the mechanical driving force generated by an engine is transferred to the power take-off to impart rotation, such as to the shaft 18. Conventional power take-offs include a rotatable coupling or other movable component which may be engaged with a linkage to impart rotation to the shaft 18.
In other embodiments, the shaft 18 comprises a hydraulic linkage. Certain vehicles include hydraulic systems, such as, but not limited to, for actuating a snow plow or shovel blade, for tipping a truck bed, or for operating a fork lift. The hydraulic system may be operable to couple with supplemental equipment, such as a hydraulic motor, with suitable linkage operable to couple with the shaft 18, to provide power thereto. Hydraulic systems and hydraulic linkages are known in the art, and are not described in detail herein.
Various embodiments are anticipated so as to control the rate of heat output of the hydrodynamic heater 2. In accordance with embodiments, the temperature change of the working fluid within the hydrodynamic heater 2 is directly related to the heat energy (BTU) generated in the working fluid and the flow rate of the working fluid. Adjusting one or both of the heat energy (BTU) generated in the working fluid and the flow rate provides a predetermined amount of fluid with a predetermined temperate exiting the hydrodynamic heater 2.
In accordance with another embodiment, the hydrodynamic heater 2 further comprises a second spacing actuator 44 coupled to the rotation member 14 operable to translate the rotation member 14 along the X-axis for varying the spacing X1 between the fluid driver disk face 115 and the fluid interactive disk face 15, as shown in
It is anticipated that the first spacing actuator 26 and the second spacing actuator 44 may be used in combination to vary the spacing X1 between the fluid driver disk face 115 and the fluid interactive disk face 15 along the X-axis.
The degree of fluid interaction with the fluid driver elements 112 and the fluid interactive elements 12 depends, at least in part, on the spacing X1 between the fluid driver disk face 115 and the fluid interactive disk face 15. A change in the spacing X1 between the fluid driver disk face 115 and fluid interactive disk face 15 changes the degree of fluid shear, and thus the rate at which heat is generated in the working fluid.
Reducing the spacing X1 between the fluid driver disk face 115 and fluid interactive disk face 15 increases the degree of fluid interaction between the fluid driver elements 112 and the fluid interactive elements 12, thus increasing the fluid shear and thus heating of the fluid. Increasing the spacing X1 between the fluid driver disk face 115 and fluid interactive disk face 15 reduces the degree of fluid shear by the fluid driver elements 112 and the fluid interactive elements 12, thus reducing the heating of the rotation member 14.
In embodiments wherein it is desirable to enable a high range of variability in the rate of heat generation, it is desirable that the range of possible values for the spacing X1 between the fluid driver disk face 115 and fluid interactive disk face 15 be relatively large.
The spacing X1 between the fluid driver disk face 115 and fluid interactive disk face 15 is a parameter that is independent of the rate of fluid flow through the fluid interaction space 52 and the rate of rotation of the rotation member 14. Thus, the rate of heat generation of the hydrodynamic heater 2 is adjustable by varying the spacing X1 without changing the rate of rotation of the rotation member 14.
In accordance with an embodiment, the rate of heat generation of the hydrodynamic heater 2 is adjustable by controlling one or more of the rate of rotation of the shaft 18, the spacing X1, and the rate of fluid flow through the fluid interaction space 52. In an embodiment, the spacing actuator 26 is used to facilitate adjustment of the spacing X1 while the hydrodynamic heater 2 is generating heat.
A variety of actuators are suitable for use as the first spacing actuator 26 and the second spacing actuator 44. In an embodiment, as illustrated in
In an embodiment, the spacing actuator 26 is a manual actuator, such as, but not limited to, a threaded screw controlled by a hand-turned knob. In other embodiments, the spacing actuator 26 is a powered actuator, such as, but not limited to, an electrically or hydraulically driven mechanism. In accordance with another embodiment, one or both of the stationary member 20 and rotation member 14 may be coupled to a shaft comprising helical thread, wherein the location of the stationary member 20 and rotation member 14 on the shaft, and thus the spacing X1 between the stationary member 20 and the rotation member 14 may be changed.
Referring again to
X1. The controller 138 may also be in communication with the shaft 18, so as, by way of example, but not limited thereto, to control the speed of rotation of the rotation member 14, and therefore, the fluid driver elements 112, which derive their motion from the shaft 18, wherein the output of the motive device driving the shaft 18 is variable and controllable.
The controller 138 in
A variety of devices are suitable for use as a controller 138, including, but not limited to, microprocessor-based controllers. Controllers are known in the art and are not described further herein.
It is appreciated that the heat output may be controlled is a variety of ways. By way of example, but not limited thereto, the fluid flow of the working fluid through the hydrodynamic heater 2 and the speed of the rotation member 14 may be increased or decreased suitable for producing a particular heat output. By way of example, a decreased fluid flow in combination with a decreased speed of rotation of the rotation member 14 may maintain a predetermined temperature at the output 36.
Although the embodiment in
The embodiment in
Based on data from the fluid temperature sensor 40, fluid flow rate sensor 42, and drive speed sensor 48, the controller 138 may adjust the speed of the rotation member 14, the speed of the fluid driver 34, and/or the spacing X1, so as to control heat generation, working fluid temperature, and/or fluid flow.
It is emphasized that the arrangement of the fluid temperature sensor 40, fluid flow rate sensor 42, and drive speed sensor 48, as shown, is exemplary only. It is not necessary for a particular embodiment to include sensors at all, or to include each of the fluid temperature sensor 40, fluid flow rate sensor 42, and drive speed sensor 48, shown in
In an embodiment, the hydrodynamic heater 2 comprises an additional sensor operable to sense the spacing X1 between the stationary member 20 and the rotation member 14.
A variety of sensors are suitable for use in a hydrodynamic heater 2 according to embodiments, depending upon the particulars of the specific embodiment of the hydrodynamic heater 2 and the type of information that is to be sensed. Sensors are known in the art and are not described further herein.
The motor drive 64 is coupled to the shaft 18 of the hydrodynamic heater 2 operable to rotate the rotation member 14 within the hydrodynamic heater 2 and therefore heat the working fluid circulating through the hydrodynamic heater 2.
The fluid handling system 70, which includes the external fluid path 132 external to the housing 30, includes the heat exchanger 72 operable to heat a target environment. Such target environment may include, but not limited to, a fluid path of a fan so as to heat air, such as a grain dryer, and liquid hoses to heat and defrost frozen ground under which the hose is placed.
It is appreciated that heat output may be controlled by selective activation and deactivation (rotation or stationary) of individual rotation members 14.
The fluid handling system 130 comprises a working fluid handling system 120, an engine cooling system 112, and an exhaust system 129. The working fluid handling system 120 comprises a fluid reservoir 121, a manifold flow control 122, an exhaust heat exchanger 123, a coolant heat exchanger 124, and one or more circulating pumps 127, all in fluid communication operable to circulate the working fluid therein. The manifold flow control 122 is operable to direct the working fluid to the hydrodynamic heater 2, the exhaust heat exchanger 123, and the coolant heat exchanger 124.
The heat generated by the hydrodynamic heater 2 is transferred to the working fluid passing within the hydrodynamic heater 2. The working fluid is collected in the fluid reservoir 121 and either directed again through the manifold flow control 122 or directed to an external heat exchanger 126 by way of an external manifold 125, or a combination thereof. The external manifold 125 is operable to provide one or more fluid take-offs to supply the heated working fluid and return cooled working fluid to/from one or more external heat exchangers 126.
The engine cooling system 112 comprises a coolant reservoir 114 for a coolant fluid in fluid communication with the engine 110 and the coolant heat exchanger 124. The coolant fluid circulates within the engine 110, wherein the heat from the structure of the engine 110 is transferred to the coolant fluid and subsequently transferred to the working fluid in the coolant heat exchanger 124. In this way, the heat from the engine 110 as well as the heat from the hydrodynamic heater 2 is used to heat the working fluid.
The engine 110 produces hot exhaust gas as a product of combustion which is directed external to the engine 110 by an exhaust manifold 128. The exhaust system 129 comprises the exhaust heat exchanger 123 which is in fluid communication with the exhaust manifold 128 and is operable to transfer the heat from the exhaust of the engine 110 to the working fluid. In this way, the heat from the exhaust as well as the heat from the hydrodynamic heater 2 and engine cooling system 112 is used to heat the working fluid.
The engine-driven heat generation system 100, therefore, utilizes the heat of the structure of the engine 110 and the heat from the exhaust of the engine 110 to augment the heat from the hydrodynamic heater 2 to efficiently provide a heated working fluid to the external heat exchanger 126.
It is appreciated that a variety of configurations of an engine-driven heat generation system may be utilized, depending on engineering design preferences and constraints.
The applications for utilizing the heat generated by the engine-driven heat generation system 100, 200 are vast. The working fluid is heated to a predetermined temperature suitable for a particular purpose. It is anticipated that most any application that utilizes the transfer of heat via a heat exchanger supplied by a heated working fluid would be suitable for use with the engine-driven heat generation system 100, 200.
In an embodiment, the heated working fluid is passed through a heat exchanger that is part of a forced-air ventilation system to provide heated air to a building. In another embodiment, the working fluid is passed through hoses that are laid out on the ground and covered with a covering so as to heat the ground, such as to thaw out frozen ground for excavation. In yet another application, the working fluid is passed through a heat exchanger of a hot water supply system that is submerged in a tank of water so as to heat the water for use. These are but a few of the vast number of applications suitable for use with the engine-driven heat generation system 100, 200.
The engine-driven heat generation system 100, 200 realizes significantly improved efficiencies over conventional hydrodynamic heaters by the utilization of the heat captured from the engine exhaust and the heat captured from the engine cooling system that are added to the heat generated by the hydrodynamic heater.
The heating system 8 comprises an internal combustion engine 110, an air handling system 35, and a hydrodynamic heater 2, all contained in an enclosure 140 on a trailer 99. The air handling system 35 is operable to draw in air external to the enclosure 140 via to air intakes 93, and exhaust air out of the enclosure 140 via an air outlet 39.
The internal combustion engine 110 is coupled to an engine cooling system 112. The engine cooling system 112 comprises a coolant reservoir (not shown) for a coolant fluid in fluid communication with the engine 110 and a coolant heat exchanger 124. The coolant fluid circulates within the engine 110, wherein the heat from the structure of the engine 110 is transferred to the coolant fluid and subsequently transferred to the working fluid in the coolant heat exchanger 124.
The engine 110 produces hot exhaust gas as a product of combustion which is directed external to the engine 110 by an exhaust manifold (not shown). The exhaust system 129 comprises the exhaust heat exchanger 80 which is in fluid communication with the exhaust manifold (not shown) and is operable to transfer the heat from the exhaust of the engine 110 to the working fluid.
An engine drive shaft 118 is coupled to the shaft 18 of the hydrodynamic heater 2 operable to rotate the rotation member 14 within the hydrodynamic heater 2 and therefore heat the working fluid circulating through the hydrodynamic heater 2.
The working fluid circulates through the fluid handling system 225 as represented in
Referring to
Heat from the engine exhaust, via the exhaust heat exchanger 80 and heat from the hydrodynamic heater 2, as well as heat from the engine cooling system 112 via the coolant heat exchanger 124, is used to heat air driven by the air handling system 35.
It is appreciated that air may also pass by the parts of the engine 110 that are at elevated temperature picking up heat before reaching the air heat exchanger 126, and therefore contribute to the overall heat output of the heating system 8.
The trailer 99 is operable to transport the heating system 8. The trailer 99 is operable to be hitched to a vehicle for movement from location to location.
It is appreciated that the heating of the air is dependent in part on the speed of rotation of the driveshaft from the engine 110 driving the rotation member 14 within the hydrodynamic heater 2. Since the embodiment of
In accordance with an embodiment, the heater system 8 further comprises a temperature controller. The temperature controller comprises a temperature sensor that is operable to monitor either the output air at the blower outlet 39 or the ambient air in the space being heated by the air coming from the blower outlet 39. An operator may input a desired temperature output or ambient temperature and the controller is operable to determine a suitable engine speed operable to maintain the operator desired temperature.
Although specific embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations calculated to achieve the same purposes may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. Those with skill in the art will readily appreciate that the present invention may be implemented in a very wide variety of embodiments. This application is intended to cover any adaptations or variations of the embodiments discussed herein.
Persons skilled in the art will recognize that many modifications and variations are possible in the details, materials, and arrangements of the parts and actions which have been described and illustrated in order to explain the nature of this invention and that such modifications and variations do not depart from the spirit and scope of the teachings and appended claims contained.
Number | Date | Country | |
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61311379 | Mar 2010 | US |
Number | Date | Country | |
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Parent | PCT/US11/27457 | Mar 2011 | US |
Child | 13452992 | US |