The present invention relates generally to the field of electrical power generation. More specifically, the invention relates to improving the recapture of energy lost to aerodynamic drag during operation of a vehicle.
There have been many prior approaches to capturing energy associated with moving motor vehicles, but thus far, improvements have continued without approaching any theoretically optimized solution. Examples of prior approaches directed to the capture of energy associated with moving vehicles are dominated by systems having roof mounted fans exposed to the air passing over the roof. These systems all suffer from the fact that they add extra aerodynamic drag to the vehicle due to their frontal surface area being exposed to the flow of air. Examples of other systems for recovering some of the energy otherwise lost to aerodynamic drag include the following.
U.S. Pat. No. 10,669,992, dated Jun. 2, 2020, “Wind power collection and electricity generation system” describes a technique for collecting the wind energy created by moving motor vehicles. This patent recognizes that energy is available as a result of the movement of a vehicle through the air but directs the collected energy to a central location instead of making the captured energy available to the individual driven vehicle. Thus, the captured energy is not useful for the driven vehicle, such as for extending the range of a vehicle being driven.
U.S. Pat. No. 10,533,536, dated Jan. 14, 2020, “Wind power generating device installed in a vehicle” describes a wind power arrangement installed on a vehicle and intended to provide a continuing supply of electrical energy, even when the vehicle is not moving.
U.S. Pat. No. 10,479,197, dated Nov. 19, 2019, “Wind powered system for vehicles” discloses another wind powered system which includes “a plurality of wind tunnels, a plurality of rotary fans provided in each wind tunnel, a plurality of alternators connected to the plurality of rotary fans to generate electricity, a transformer connected to the plurality of alternators, electric components connected to the transformer, and a battery connected to the transformer and the electric components. The transformer is supplied with the electricity generated by the alternators and outputs electrical energy with a voltage to be supplied to at least one of the electric components and the battery. The plurality of wind tunnels have a plurality of intake inlets which are separated and apart from each other and a single outlet shared by the plurality of wind tunnels.”
U.S. Pat. No. 10,173,663, dated Jan. 8, 2019, “Total electric vehicle”, discloses a system wherein an electric vehicle receives propulsion power from “two sources of static, stored, electric power and three sources of Dynamic, generated electric power. The two stored sources are a Battery and a supercapacitor system. The three sources of Dynamic power are: (1) Regenerative power in both the braking, deceleration phase of travel, the downward slope of travel over some extended distance, and part of cruise control; (2) Power from a modified Squirrel Cage generator; and (3) Power through the solar silicon panels. The Static and Dynamic powers are fed into the current Consolidator, Distributer, and Controller (CDC) systems to provide electric power to the drive motors. The total distance travelled is the sum of the Static, stored power plus the generated power of the Dynamic system.”
Still, even with all the work that has been done, it has been recognized that further improvements are necessary. This is made clear in U.S. Pat. No. 10,072,641, dated Sep. 11, 2018, “Apparatus for generating energy from a fluid flow induced movement of a surface structure relative to an opening to a cavity in a frame” that discloses another approach to capturing wind energy in a moving vehicle. This disclosure identifies limitations in the prior art, stating, for instance, that “Generators harnessing energy from a fluid flow (such as air) are known within the art, however such generators typically have turbines or propellers which have a large cross-section. The movement of the medium creates a motive force upon the turbine or propeller, which is connected to a device to convert the movement into electricity. But the large cross-sections of these traditional designs increase the amount of wind resistance presented by the generators, limiting the practicality of their application in certain fields.” This patent further states, “There is a need for a device that can generate electricity from relatively lower levels of motive force and provide smaller cross-sections. There is also a need for scalable, stackable devices to generate electricity in locations where traditional devices are not suitable. The increased use of electric and hybrid engine systems in vehicles has also created an increased need for ways of generating electricity to recharge batteries.”
In other instances of capture of wind energy for electrical power generation, it is ordinary practice to place a windmill, to the extent possible, away from any interfering structures. Thus, windmill farms are placed in wide open spaces, such as flat fields or offshore, where there is no interruption of the incoming wind flow. Similarly, even for sailboats, it is common to place a windmill-type structure on a separate mast.
According to the invention, energy from the apparent wind can be harnessed in a moving vehicle in an efficient manner relative to pre-existing approaches. This is accomplished by providing a system in which wind powered generation devices are positioned at locations on the vehicle where there is high air pressure resulting, for the most part, from forward facing portions of the vehicle impacting the air as the vehicle progresses. At these locations, wind energy is concentrated and can be captured efficiently by a wind-based generator while at the same time avoiding the creation of significant incremental aerodynamic drag in the vehicle. By directing this energy to the onboard vehicle energy requirements there is a net improvement in the vehicle's travel range. The invention has great utility in electric and hybrid vehicles, extending the range significantly.
It is an object of the present invention to improve the range of a vehicle by recapturing some of the energy otherwise lost to aerodynamic drag.
It is another object of the present invention to capture the greatest amount of wind energy possible relative to the amount of wind resistance added to a moving vehicle on which the wind generation system is mounted. In this manner, the system captures energy that would otherwise be wasted.
It is another object of the present invention to provide a wind generation system that can be used in a variety of vehicle applications without unnecessarily increasing the aerodynamic drag of the vehicle, and in which any increases in aerodynamic drag are more than offset by the energy generated by the system.
These and other objectives of the invention are accomplished through a combination of highly efficient device design and highly sophisticated analysis of the overall vehicle arrangement. These design and analysis components of the implementations of the invention call for identifying specific areas on the vehicle where wind forces are relatively high, yet where the forces can be harnessed without creating an undesirable offsetting incremental counterforce. In motor vehicles any added drag to the vehicles aerodynamic performance is important, particularly in electrically powered vehicles where vehicle range is of major commercial importance. Thus, the invention facilitates capture of the wind forces for electrical power generation without adding an incremental equal and opposite reaction. This is done by locating regions of the vehicle structure where wind forces already impede the forward movement of the vehicle through the air and harnessing a substantial portion of the existing energy loss for electrical power generation. Importantly, the invention also calls for the avoidance of placing wind energy recapture devices at locations where the incremental aerodynamic drag exceeds the energy that can be recaptured. These advantages are further enhanced by placing the outlets of the energy recapture devices at locations on the vehicle where there is low pressure, contributing to the overall energy recapture by utilizing the highest possible pressure differentials between device input and device output.
Referring to
The electrical components of the wind-driven electric generator are shown in
In an automotive application, a one speed gear box can be employed in order to keep dimensions to a minimum within the vehicle embodying the invention. In other implementations it will be feasible to use a direct drive system. In a preferred embodiment, a tensioning pulley arrangement is provided having a first pulley 231 attached to the drive axel, a generator pulley 233 attached to the generator axel and a tensioning belt 232 engaging both pulleys 232 and 233. This pulley system has two specific functions: number one is to negate the centrifugal force of the aluminum shafts and to prevent any rotation requiring realignment during maintenance. Another is so the pulley can absorb such tensions usually absorbed by the drive shaft that produce heat due to metal on metal contact at bushings and bearings making this implementation of the invention 10-13 percent more efficient than systems without the pulley system at temps ranging above 20 degrees Celsius. The single speed gearbox system provides more output power but also requires higher speeds to work at its optimized voltage and current requirements. These gears are sized according to spec, in terms of overall diameter dependent on depth and height of corresponding vehicle design space. For a multispeed gearbox, a second gear (not shown) could be placed adjacent to the single gear 222 shown in
With reference to
The blades 120 and cone 115 structures are shown in
The length of the impeller is also to be selected as a function of the speed of the incoming airflow as with the angle of the blades. The weaker the incoming airspeed, the longer the impeller should be to develop the torque needed for effective power generation. For incoming airflow speeds averaging less than 20 mph an impeller having a length of at least 3 inches (measured along the axis of the drive shaft) should be selected and the angle of the edge 51 of the blades relative to the axis of the drive shaft should be between about 40 degrees and 50 degrees.
In order to locate the system for optimum performance on a motor vehicle, it is desirable to custom design both the vehicle and the system.
An incremental improvement in efficiency can be achieved by situating the outlet of the wind generation unit at a low pressure area of the vehicle. Generally, this might be along the forward inner surface of the wheel well 1101 in
Although not shown in the drawings, many other vehicles have wind pressure peak areas that are well suited for utilization of the present invention. For instance, wind driven vehicles such as sailboats often employ a wind powered generator. These systems typically rely on a windmill-type generator sitting atop a pole near the stern of the boat. Unfortunately, while such a system does indeed generate electricity, the physical structure of the system directly interferes with the sailing efficiency of the boat. The entire windmill is exposed to the wind and directly creates aerodynamic drag opposed to any attempt to make headway into the wind. The present invention can generate electricity from the wind without interfering with forward progress. To accomplish this, the wind generation system is installed along a portion of the dodger where the dodger is already blocking the wind. The inventive system can be installed without creating any incremental wind resistance, avoiding the disadvantages of prior sailboat wind generators. Power boats can also benefit from the invention. The range of a powerboat is a direct function of the fuel capacity and the fuel burn rate per mile. Adding the invention's system to a powerboat reduces the amount of fuel needed to recharge batteries and operate vessel accessories thus reducing power requirements from the fuel and increasing the miles per gallon. As a result, the boat will be able to make longer voyages when the inventive system is employed than would otherwise be possible.
A preferred embodiment of the invention includes four inlets and is constructed as a modular unit. This design consists of four 5-inch diameter inlet tubes for the main housing and a separate 3-inch diameter housing associated with each inlet for the respective gears and motor. A turbine is housed in each of the four main tunnels while the battery, gears and motor are located in the separate side chambers. Details of the design include inlet tubes having a 5-inch diameter and enclosing the turbine and drive axel for each tube. There is a 12V and/or 24V motor (low internal resistance with forward/reverse gear set) along with 2 gears of thermoset plastic and a safety pulley arrangement. An air flow sensor is also provided for each tunnel. The pertinent design considerations are:
P=I
2
R, I=P/E, R=P/I
2
, V=P/I
where m1 and m2 are the mass of the two pulleys
The theoretical voltage, current, and power values based on compressed air testing provided an output of V=26 volts and I=20 mA with a resultant power generation of P=2.1 kWh as the power regenerated towards the battery back during 1 hour of drive time. This is based on highway simulation of a velocity at
The theoretical Power generated at these conditions under pressurized air testing: resulted in:
Test Results for this quad system: (all results dependent on high voltage harness, maximizing current within a vehicles HVAC or battery tray system, at different voltage outputs depending on gear ratio)
12V @ 1500 RPM=1.2 kWatts instantaneously
24V @ 1500 RPM=2.4 kWatts instantaneously
12V @ 1500 RPM Average Trip Distance=1250 Miles; Average mph=67.5 mph (Highway Speeds); Average Time 18.52 hours, 1,111.2 minutes, 66,672 seconds
24V @ 1500 RPM Average Trip Distance=1250 Miles; Average mph=67.5 mph (Highway Speeds); Average Time 18.52 hours, 1,111.2 minutes, 66,672 seconds Power Generated=34,669.44 Wh or 34.7 kWh
RPM Average of 1500 RPM for all testing wattage,
5,000 Watts of Power needed to run HVAC system within truck cabin (Average 9 hour run time) 45 kWh total requirement
3,000 Watts of Power needed to run Heater within truck cabin (Average 9 hour run time) 27,000 kWh total requirement
Average 1250-mile route will generate enough energy to operate the HVAC system for 2.9336 hours: 12V Motor
Average 1250-mile route will generate enough energy to operate the HVAC for 6.9339 hours: 24V Motor
Average 1250-mile route will generate 4.8893 hours of Heater run times: 12V
Average 1250-mile route will generate 11.55648 hours of Heater run times: 24V
Electric Semi Truck Platform: Around 200 kWh 620-mile range
3,220 (Watt-Hours per mile traveled) to generate 1.04 miles of range per 62.0 miles at highway speeds
Energy Generated per Single Battery Charge: 60 miles added per 150 kWh battery pack (10.19% increase)
In a general sense, the implementation of the invention can involve an electrical generation system employing multi-serried or parallel turbine modules comprising blades which harness air to use as a catalyst for rotating a shaft attached to a gear set which ultimately generates power through a generator that can be directed by an on-board regenerative ECU towards battery cells, a vehicle inverter, or to a separate power management system, wherein said power is sufficient to cover the vehicle's parasitic overhead and to power an on-board management system. A turbine module, as used herein, means a wind driven electrical power generator employing at least one rotating blade or set of blades constructed to have a housing with a lower edge and an upper edge. When multiple turbine modules are employed, a single housing can be employed for the plurality of turbine modules. For convenience, turbine modules may be referred to herein simply as turbines. In operation, there is an inlet end through which high pressure (forced air) enters the turbine and then an outlet end through which air exits the turbine. Having a greater pressure differential from inlet to outlet provides greater opportunity for electrical generation, largely because there will be more airflow through any given structure when the pressure differential is greater.
In a preferred embodiment, an electrical generation system having multiple turbines can generate enough current within the on board regenerative ECU and power management system so that instantaneous voltage and power output has a significant impact to update said on board vehicle management systems and main ECU for range extension at highway speeds (high enough velocity to overcome internal resistance). In fact, it is preferred if the power output when the vehicle is travelling at highway speed is sufficient to fully power the vehicle management system and main ECU.
As an additional feature, the power supplied by the turbine module is used for providing power for vehicle propulsion through a vehicle inverter that may power one or both of the front and rear drive units in an electrically propelled vehicle. To provide vehicle architecture flexibility, a low voltage harness may be integrated into the vehicle (depending on configuration) for distribution of the power generated by the turbines. Additionally, the turbines can be used to provide power for battery cells within vehicle battery tray. Battery cells, managed through a vehicle battery management system, can actively be controlled by monitoring the voltage supplied by the turbines. Further, the turbine output can be utilized for providing power for on-board vehicle management systems, including overall parasitic overhead. These management systems cover and are not limited to audio, LED lighting, electronic dash sensors, active electronic stability control features including ride height and suspension monitoring systems, and other on-board vehicle systems.
In practice it is also possible to integrate individual turbine units into a multi-turbine array that can be laid out in substantially any desired configuration. The housing for such systems is created for multi directional integration where maximizing surface area of drag naturally taken off the front of a vehicle is at a maximum for power generation. This could involve laying out the individual turbines within one or more housing systems in a horizontal fashion. This includes corresponding gear boxes attached to turbine shafts, additional motor/generator attachments, and all other design features that can be incorporated for transmission of voltage or power. Similarly, the layout could be vertical or diagonal or even in a set of rows and columns or any other desired layout. Selection of the locations of the turbines can be facilitated by determining the locations on the vehicle responsible for the greatest amount of aerodynamic drag when moving at highway speeds and then placing the turbines at these locations. Also, selection of as many specific high drag locations as possible will facilitate provision of the maximum number of turbines and thus the maximum net power generation. Net power generation takes into consideration any residual drag occurring at locations where the turbines are placed. As a result, provision of additional turbines is effective only for locations where the drag is higher than the aerodynamic and electrical losses inherent in the placement and operation of the turbines.
Desirable locations for turbine placement, illustrated in
Initial design aerodynamic efficiency tests with concept electric vehicles were conducted resulting in identification of these locations as places where the greatest aerodynamic drag was created. Several design features resulted in improved results. Arrangement of multiple inlets in a honeycomb pattern as shown in
In some situations, it might be advantageous to have a vehicle that does not exhibit some or any of the inlet openings. This might be the case for parked vehicles, where prevention of animals entering the vehicle could be desired. However, it might also be the case where a vehicle is moving at a particularly high rate of speed and the expected ratio of energy recovery through the turbine versus increased aerodynamic drag is not favorable to operation of the turbine. In this situation, closing the inlet will return the aerodynamic drag to its original level since that is preferable to maintaining the opening and creating a modest net energy loss. In an alternative embodiment, the opening can be regulated so that at excessive speeds where the inlet opening of the turbine creates too much drag for efficient operation of the turbine, the opening can be partially covered to decrease aerodynamic drag while allowing the turbine to generate sufficient electricity to make operation a net contributor to vehicle range. A concentrically closing aperture can be provided for this function.
Another reality in the design of motor vehicles is that the aerodynamic drag is not constant over a range of speeds. Different high-pressure areas come into play as vehicle speed changes. Thus, having the ability to open and close inlets to multiple turbines provides the opportunity to generate electricity efficiently at different speeds. When any particular high-pressure area does not have sufficient power generation capacity for a given vehicle speed (sufficient meaning more than enough to overcome the incremental drag) then that inlet can be covered. In this manner the range of the vehicle can be supplemented without suffering counterproductive consequences from the turbines. According to this embodiment of the invention, there can be selective control of one inlet separate from control of a second inlet, allowing for optimized overall system performance. Additionally, there are sometimes situations where the electrical system is not in need of additional regenerated power. This makes it feasible to close all (or most of) the inlets, thus providing the most aerodynamic vehicle profile. To accomplish closure of all inlets at once it is possible to provide a flap that can cover a group—up to all—of the inlets. Closing the flap can almost entirely return the vehicle's aerodynamic profile to the original design, and thus to a shape that does not suffer any aerodynamic degradation from the turbulence that would otherwise be created by the inlets. With this added feature, the vehicle can benefit from an addition operating option. When the vehicle is intentionally decelerating, it is possible to open the inlets for all of the channels and thus create aerodynamic crag to assist in slowing the vehicle. This feature can be implemented even when there is not a net power gain achieved by operation individual ones of the turbines. In a preferred implementation, there is a combination of the first mode of operation wherein selective opening and closing of individual inlets makes it is possible to engage only those channels that have a net power contribution, and also having a second mode of operation involving the opening of all of the channels, even those not providing a net contribution to power, whereby vehicle deceleration can be facilitated and electrical power can be derived because there is no need for a net power contribution when vehicle deceleration is desired.
To determine whether any particular area on the vehicle is suitable for generating net power at any particular vehicle speed, that is, generating more power than is lost due to incremental aerodynamic drag, the following equations can be used to calculate the force/power required to overcome a given amount of drag.
Then, it can be determined whether placement of the turbine at the identified location will be effective at any given target speed. By identifying the vehicle speed at which each identified location becomes available for incremental power generation, it can be determined whether to place a turbine there, and if so placed, whether and at what speeds to close the entrance to block airflow in order to return the surface to the original aerodynamic profile. Still further, it can be determined whether to partially open or close each inlet separately.
For determining the amount of pressure drop through the channel that can be created, and thus to determine the utility of an incremental channel in the system, it is helpful to determine the maximum achievable air flow rate. This can be calculated as follows:
Within each channel there will be a pressure drop and the following approach is employed to determine the pressure drop through the channel:
The drop in pressure within the channel (along with channel cross sectional area), will influence the velocity of air moving through the channel. This analysis is available to determine the venturi location and design. The change in air velocity is calculated as follows:
The changes is air velocity are correlated with changes in the air's kinetic energy. The resultant Change in kinetic energy is calculated as follows:
While the foregoing discussion has addressed primarily the placement of the inlets to the air channels, the outlet placement is also a potential factor in improving system performance. Outlet location for each implementation can support obtaining maximum overall efficiency as well as “neutralization of drag” for net energy transfers. In automotive applications, the outlets have multiple possibilities, each with its own consequences. The outlet airflow can be released into a low-pressure area, and thus as a larger volume, into a vehicle's front wheel well. This provides for increased pressure release and decreased velocity release improving the characteristics of overall air flow through the system, with minimum impact of the aerodynamic drag of the vehicle. This outlet location favorably impacts overall vehicle drag coefficient by reducing friction inside the front wheel well as the “back pressure” effect causes front air dynamics to be pushed down the side of the vehicle (where it's intended by in the original vehicle design). The net result is that air flowing along the side of the vehicle is not caused to have undesirable velocity vectors directed toward the inside of a wheel/tire. Outlet airflow can alternatively be released to a vehicle's front air duct in front of the vehicle's wheel wells causing another pressure change to occur changing the air velocity vector's direction. This has a similar effect as releasing the airflow into the wheel well with the only significant differences occurring at outlet site and restrictions on outlet size due to the vehicle design. The outlet airflow could also be released to a vehicle's radiator inlet for increased cooling dynamics as well as reduced impact of air velocity for reducing frontal resultant force against the radiator. Impacts are equivalent to those above with an exception of air dynamics. Without a direct outlet to the exterior of the vehicle, air turbulence is relevant in finding ways for pressure to escape, causing a missed opportunity to decrease vehicle drag.
Dimensionally, there are limitations with automotive design that influence outlet placement and configuration, inlet placement and configuration, venturi dimensions and change in volume, and other constraints concerning the aerodynamics. For instance, angles between the vehicle axis and the impeller axis should preferably be limited to 34 degrees due to drag capture and added turbulence that is noticeable for air velocity loss before a venturi inlet. This impacts the positioning of the inlet as its angle towards such outlets are also desirably to such that no terns of more than 34 degrees are introduced to the airflow through the channel either before or after the venturi. This results in a desired limit of 68 degrees between the inlet orientation and the outlet orientation. In practice this relates to the dual turning constraint with respect to a vehicle's front radiator and wheel well positioning from frontal grill position (and or fog light application, frontal horizontal angle).
Channel constraints are also noticeable in constructing other potential variations inside vehicle platforms. These constraints can be seen through multi-variant venturi blade configurations, material constraints, motor constraints, and additional motor-controller dimension constraints. Inside the channel consists of direct aerodynamic relationships that impact every air velocity vector for every added surface area impact point (every strip of filament or material) that change the drag relationship within every portion of the channel. Such constraints can be analyzed as set forth above to determine the best dimensions and positioning of the components of the invention, including not only the air handling components but also the motor, controllers, wiring, and other components required for power to be transferred to desired locations within the vehicle.
In summary, exemplary systems embodying the invention have mass product potential due to the ability to help generate power for HVAC systems within commercial vehicles as well as electric vehicle platforms for longer range capabilities. Due to exemplary system size and light weight, users are able to integrate multiple variations within the same vehicle without compromising range due to weight and load increase. In other words, exemplary systems have been found to have a 42:1 ratio of mileage to weight added in an analytically modeled 200 kW lithium ion battery pack standard propulsion system (ETA range around 500-550 miles depending on commercial load). There is no such thing as free power, but exemplary systems have been found to offer desirable power “regeneration” based off a commercial vehicle's own drag within the front of the cab to recharge any electrical powered system. Hence, exemplary systems have a direct correlation to finding a solution to range anxiety in electric vehicle platforms without finding different battery pad (solutions and for a fraction of the cost to produce.
In accordance with various exemplary embodiments, a benefit of the invention is the potential for integration and use on a commercial vehicle that makes a regenerating tunnel turbine unique. Unlike traditional turbines, exemplary systems are located within a wind funnel, maximizing air flow through multiple sets of blades with as much surface area as possible to capture high speed wind pressure. An exemplary unique 3-D printed funnel allows for easy accessibility on a commercial vehicle to allow for safety, noise degradation, and integration location flexibility. An exemplary dual blade setup is also a part of the specific design that enables the product to capture additional wind flow exiting the first set of receptive blades to maximize air impact (natural drag). Exemplary systems sit in a class of their own by really being one of the first few “regenerative power” products on electric or non-electric vehicle setup systems. Exemplary systems are able to be integrated on any vehicle (including electric semi trucks with low drag coefficient front ends) to help power all electrical systems within all vehicle classes.
In various exemplary embodiments, a regenerating tunnel turbine is a product that captures wind drag (mainly vehicles) and harnesses the power generated to transmit to multiple different applications (HVAC systems, chassis battery life, heat generators, etc.). Exemplary embodiments utilize receptive blades inside a “funnel” to capture as much air flow as possible and these blades turn a corresponding shaft that is regulated through a series of bearings for safety purposes. Through a dual shaft set up with additional gears it allows the system to generate beneficial amounts of power to a multitude of different applications. Exemplary embodiments may be utilized, for example on a semi-truck platform, to constantly generate power (especially at highway speeds) with zero (or nearly so) incremental power exertion.
While the invention has been described herein with respect to several specific embodiments, as well as with respect to some of the optional applications of the invention, it is to be understood that this description is for the purpose of disclosing at least one manner of making and using the invention, including the best mode as known to the inventors. Not all manners of making and using the invention are specifically described with respect to the several embodiments set forth herein and the scope of the invention is not limited to the specific embodiments disclosed herein.
This application claims priority on commonly owned and previously filed U.S. Provisional Patent Application No. 62/924,926, filed Oct. 19, 2019. The entire disclosure of U.S. Provisional Patent Application No. 62/924,926, filed Oct. 19, 2019, is hereby incorporated by reference.
Number | Date | Country | |
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62924926 | Oct 2019 | US |