Dynamic fan speed control for aerodynamic drag reduction

Abstract

A method, system, and apparatus are provided for optimizing control of the rotational speed of a fan in a vehicle in order to reduce the aerodynamic drag of the vehicle at a given operating parameter and, thus, improve the fuel efficiency of the operation of the vehicle. Certain example embodiments include determining an optimized rotational speed of a cooling fan of the vehicle to reduce overall fuel requirements at a given operating condition, and controlling the rotational speed of the fan at the optimized speed in order to minimize the refueling requirements of a prime mover of the vehicle.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 585,666, filed November 14, 2017, which is incorporated herein by reference in its entirety. Background Technology

[0003] This application generally relates to the dynamic control of cooling fan speed in vehicles equipped with prime movers, providing a method, apparatus, and system for reducing aerodynamic drag of the vehicle by optimizing fan speed. Numerous methods, systems, and apparatuses have been developed to reduce aerodynamic drag in vehicles to improve fuel efficiency. However, these developments continue to be hampered by many limitations and drawbacks, including operational or design complexity, costly construction or implementation, and a lack of interchangeability between different vehicle configurations. Therefore, there remains a significant need for further improvements to systems, apparatus, and methods for reducing aerodynamic drag.

[0004] The content of the explanatory implementation plan

[0005] To clearly, concisely, and accurately describe the illustrative embodiments of this disclosure, the ways and processes of making and using this disclosure, and the purposes for which this disclosure can be practiced, made, and used, reference will now be made to certain exemplary embodiments, including those shown in the figures, and these embodiments will be described using specific language. However, it should be understood that this is not intended to limit the scope of the invention, and that the invention includes and protects these changes, modifications, and additional applications of the exemplary embodiments that will occur to those skilled in the art. Summary of the Invention

[0006] The embodiments disclosed herein include a unique system, method, and apparatus that optimizes the control of the fan speed in a vehicle in a manner that effectively reduces the aerodynamic drag of the vehicle and thus improves the fuel efficiency of vehicle operation. Some exemplary embodiments include unique methods, apparatus, and systems for determining an optimal speed for a vehicle's cooling fan to reduce overall fuel demand under given operating conditions, and for controlling the fan speed at an optimized rate to minimize fuel refueling requirements for the vehicle's prime mover by improving the vehicle's aerodynamic drag characteristics. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to help limit the scope of the claimed subject matter. Other embodiments, forms, objects, features, advantages, aspects, and benefits will become apparent from the following description and drawings. Attached Figure Description

[0007] Figure 1 This is a schematic diagram illustrating certain aspects of an exemplary system.

[0008] Figure 2 It shows that it can be controlled according to Figure 1 A flowchart of certain aspects of an exemplary process executed in an exemplary system.

[0009] Figure 3 It shows that it can be controlled according to Figure 1 A flowchart of certain aspects of an exemplary process executed in an exemplary system.

[0010] Figure 4 This is a flowchart illustrating certain aspects of an exemplary process that can be executed in an exemplary control system.

[0011] Figure 5 This is a graph illustrating certain aspects of the reduction in vehicle aerodynamic drag in an exemplary system.

[0012] Figure 6A and Figure 6B This is a graph illustrating some aspects of the reduction in the work required to maintain vehicle speed in an exemplary system. Detailed Implementation

[0013] To facilitate understanding of the principles of the invention, reference will now be made to the embodiments shown in the accompanying drawings, and these embodiments will be described using specific language. However, it should be understood that the scope of the invention is not thereby limited, and any changes and additional modifications to the illustrated embodiments, as well as any further applications of the principles of the invention as commonly perceived by those skilled in the art to which this invention pertains, are contemplated herein.

[0014] refer to Figure 1 The diagram schematically illustrates a system 100 including a vehicle 102 and a control system 104, the vehicle having a prime mover 106. The prime mover 106 can be or includes any power source, such as an internal combustion engine, a hybrid engine, an electric motor, a battery, or a fuel cell. The prime mover 106 of the vehicle 102 can operate in different vehicle propulsion modes, such that the prime mover 106 provides torque to a transmission 108, which in turn provides torque to the drive wheels 110 of the vehicle 102 to cause the vehicle to move in one direction.

[0015] The vehicle may include a cooling system 112, which may include a radiator 114, a booster air cooler 116, an air condenser 118, and various oil coolers, etc. The cooling system 112 includes a fan 120 and a coolant path 122. In an embodiment, the radiator 114 and the cooling fan 120 are operable to transfer heat from the coolant within the closed-loop coolant path 122 to the environment. The fan 120 may preferably be a conventional cooling fan that can be controlled to drive air rearward from the front region 124 of the vehicle 102.

[0016] Cooling system 112 may include one or more coolant pumps (not shown) driven by the operation of prime mover 106. Cooling flow path 122 is in thermal communication with prime mover 106. In an exemplary embodiment, thermal communication is provided by a portion of coolant flow path 122 passing through one or more flow channels disposed in prime mover 106.

[0017] When the vehicle is in the forward direction (towards) Figure 1 When the vehicle moves to the left, the front area 124 of the vehicle 102 encounters ambient air and is... Figure 1 Arrow AF in the diagram represents the force of the airflow exerting aerodynamic pressure on the moving vehicle 102, thus creating drag on the forward movement of the vehicle. Prime mover 106 provides power to vehicle 102 to overcome this aerodynamic drag. Therefore, reducing aerodynamic drag helps improve the overall fuel efficiency of the vehicle. The front region 124 may include a grille through which some ambient air can reach fan 120 as the vehicle moves forward. The ambient air may be stationary relative to the ground or may be moving upwind. The wind direction may be parallel to the vehicle's forward direction or may be at an angle (angle of attack or yaw) relative to the vehicle's forward direction or relative to the longitudinal axis of vehicle 102.

[0018] Vehicle 102 is controlled by control system 104, which is configured to perform certain operations. Figure 1 The diagram is schematically shown. Control system 104 may be an electronic control system. The electronic control system may include on-board and off-board systems, as well as components operatively coupled to facilitate the functioning of control system 100 and / or vehicle 102. Although in... Figure 1 The control system 104 is schematically represented as an in-vehicle system, but it should be understood that the modules, systems, functions, and components of the control system 104 may be distributed between the in-vehicle and remote systems and the components of the control system 104, which may be operatively coupled via wireless connections or other remote components for transmitting signals and commands therebetween. In an exemplary embodiment, the control system 104 may include an in-vehicle controller 126 configured and operatively coupled to receive and interpret signals from other components of system 100 and other components of vehicle 102 and sensors 128. The control system 104 may be configured and operatively coupled to output signals to components of system 100 and / or vehicle 102, including outputs to and control of various actuators of vehicle 102 and its systems and components. Some of the various sensors 128 and actuators that may be employed are described in more detail below.

[0019] The control system 104 optionally controls the operation of the cooling fan 120 of the vehicle 102 via an on-board controller 126. This can be achieved by the control system 104 sending signals to the motor of the fan 120 and / or a fan control mechanism (not shown), which engages with the shaft of the fan 120 to control the rotation of the fan and thus the movement of the fan blades. This control can be performed independently of the operating speed of the prime mover 106. The operating states of the cooling fan can include braking; free rotation; or driving. The operating states of the fan can be controlled by the control system 104, which guides the operation of a mechanical fan clutch mechanism that can engage the shaft of the fan 120 to operate in these states.

[0020] In the braking state of fan 120, braking torque is optionally applied to fan 120 by the action of a fan control mechanism implemented as a fan clutch, thereby preventing fan rotation. In the fan braking operation mode, ambient air passing through the fan blades during vehicle movement does not cause fan 120 to rotate.

[0021] In the driven state of fan 120, fan 120 is rotated about its axis by applying power from components of vehicle 102. This power may include mechanical power generated due to mechanical coupling with prime mover 106, or may include electrical power supplied by a power source in vehicle 102, such as a battery or generator (not shown), in which case fan 120 is disengaged from prime mover 106, such that the driving force is applied by electricity rather than by the mechanical driving force of prime mover 106. In any case, the fan clutch mechanism may be controlled and operably engaged by control system 104 to control the rotational speed of the fan 120 shaft. In an exemplary embodiment, the fan speed may be controlled at multiple different selected speeds (revolutions per minute, rpm).

[0022] In the free-rotation state of fan 120, fan 120 is neither braked nor driven, and can rotate freely by the force of ambient air acting on the fan blades when vehicle 102 is in motion or when moving air impacts the vehicle. Under typical vehicle operating conditions, conventional moving vehicles usually set their cooling fans to braking mode or free-rotation operating mode.

[0023] In drive mode, fan 120 can be controlled by control system 104 to operate at a specific speed to meet operator requirements or to satisfy operating parameters or settings of vehicle 102. For example, control system 104 can be configured to control the operation of the fan clutch mechanism to drive the shaft of fan 120 to rotate at a specific selected speed. The fan speed can be controlled based on prime mover operating parameters such as prime mover cooling requirements. For example, when it is determined or estimated that the component temperature of prime mover 104 exceeds a temperature threshold, control system 104 can command a higher fan speed to help reduce the temperature.

[0024] Vehicle 102, system 100, and / or prime mover 106 may also include multiple sensors 128. Examples of such sensors may include sensors for detecting or estimating component temperature, vehicle speed, vehicle environmental conditions, fuel consumption rate, and other relevant data. It should be understood that the foregoing sensors and sensor arrangements are merely several non-limiting, illustrative embodiments of sensors and sensor systems to which the principles and techniques disclosed herein can be applied. It should also be understood that the sensors 128 used may be physical sensors, virtual sensors, estimators, and / or combinations thereof.

[0025] According to an aspect of the invention, a dynamic control method or system is used to determine the optimal speed of the fan operation controlled by the control system 104 to meet the operating requirements of the prime mover while maximizing fuel efficiency. The inventors have discovered that during forward movement of the vehicle 102, the aerodynamic drag of the vehicle 102 can be reduced by the operation of the cooling fan 120. During forward movement, the operation of the fan 120 alters the airflow field around the front region 124 of the vehicle. The inventors have discovered that for a given vehicle under given operating conditions, an optimal fan speed can be determined at which the maximum reduction in aerodynamic drag relative to the given vehicle 102 can be achieved. The operation of the fan at the determined optimal speed also allows for a reduction in the work (horsepower) required to maintain a constant vehicle speed. Therefore, the optimized fan speed thus determined can be selected as the operating setting for the vehicle 102 to improve the fuel efficiency of vehicle operation by reducing the horsepower required for the operation of the prime mover 104.

[0026] Figure 2 An overview of an embodiment of system or process 200 is shown, which includes measuring the flow dynamics of a vehicle under certain operating conditions to determine an optimized cooling fan speed in order to improve the fuel efficiency of a vehicle operating under given operating parameters or requirements. Process 200 begins at operation 202 and includes the step of determining or calculating values ​​of the vehicle's aerodynamic drag characteristics. The aerodynamic drag characteristics may preferably be the vehicle's aerodynamic drag, which is the sum of the vehicle's front area and a given vehicle aerodynamic drag (C). dThe product of A) can be determined by setting the drag coefficient and front surface area of ​​the vehicle under given operating conditions. d A calculates.

[0027] In an exemplary implementation, it can be achieved by utilizing, for example Figure 1 The modeling system 130, schematically represented, is used to determine the CdA value at operation 202. For example, a method or system according to the invention may include the use of modeling system 130. Modeling system 130 may include means and systems for performing a three-dimensional computational flow dynamics modeling process to determine a coefficient for the drag Cd value of a given vehicle 102 under given operating conditions, which may then be multiplied by a measured or known front surface area A of the given vehicle 102 to produce a value for aerodynamic drag CdA. The process at operation 202 may include conducting tests to generate model data in a test environment representing the aerodynamic drag characteristics of the given vehicle 102 under specific operating conditions or parameters.

[0028] In the example, Figure 2 Operation 202 may include exposing a sample vehicle 102, for example, a truck of a given brand, model, and year, to an airflow in a system's test chamber, the system being designed to measure flow dynamics and generate a dataset representing the Cd characteristics of the vehicle 102 under set test conditions, such as a vehicle aerodynamic wind tunnel. The test conditions may preferably be variable to allow the tester to expose the vehicle to different conditions representing varying operating conditions or parameters. In examples, varying operating conditions may include variable airflow rates to represent different vehicle speeds and / or different wind speeds and angles (yaw). For example, wind speeds may be changed to produce Cd values. d A calculation that reflects the movement of a vehicle at a given vehicle speed (vehicle ground speed, in miles per hour, mph) as the wind traveling at a given speed on the area in front of the vehicle (e.g., wind speed in miles per hour, mph reflecting the operation of a headwind pointing at zero angle towards the area in front of the vehicle).

[0029] In the example of operation 202, test conditions representing variations in operating conditions may include variable airflow directions (e.g., different yaw conditions), representing different angles at which wind or airflow AF impacts vehicle 102 relative to its longitudinal or vertical axis or relative to its direction of movement. In this example, the wind angle may be defined as the angle formed on a horizontal plane between the longitudinal axis of vehicle 102 and the axis of the wind direction near the front region 124 of vehicle 102.

[0030] The varying test conditions at operation 202 are used to generate, edit, compare, and store datasets that can be used to calculate or estimate the drag coefficient of a vehicle. These datasets correspond to a specific set of test conditions representing actual operating conditions. Iterations are repeated under different test conditions to generate datasets corresponding to a series of different operating conditions, preferably including operations at a range of wind speeds and angles.

[0031] Figure 2 The operation 202 of the system and method represented herein preferably includes: testing to edit data on the aerodynamic drag characteristics of the vehicle under a series of varying operating conditions as described above, while controlling the fan 120 of the vehicle 102 to operate at a series of set fan speeds. For example, the series of set fan speeds may include a range of speeds selected from 0 to 700 revolutions per minute (rpm). The process is iteratively repeated under varying operating conditions (a series of wind speeds and a series of wind angles) to collect a dataset showing the aerodynamic drag characteristic values ​​of the vehicle under each set of operating conditions, while the fan is set to rotate at each of the series of set speeds. The resulting dataset can then be recorded, edited, compared, and stored using the computer system of the modeling system 130. The dataset can be stored and used by the computer system of the modeling system 130 and / or the control system 104 in additional calculations and determinations, including creating tables representing data on the aerodynamic drag characteristics based on the fan speed.

[0032] exist Figure 2 In operation 202, the iterative tests described above can be repeated on multiple different sample vehicles of various brands, models, and years to record, edit, compare, and store the aerodynamic drag characteristics C associated with each sample vehicle. d The dataset A. The dataset can be stored and used by the computer system of modeling system 130 and / or control system 104 in additional calculations and determinations, including creating tables representing data on aerodynamic drag characteristics for each specific brand, model, and year of vehicle under a set of operating conditions related to fan speed. As an alternative to or supplement to the aforementioned test chamber process, different test methods, such as scaled model wind tunnel testing, can be used to perform the test process to generate aerodynamic drag characteristic values ​​in operation 202.

[0033] exist Figure 2 In operation 204, the fan power requirement and aerodynamic power requirement required to overcome the aerodynamic drag of vehicle 102 at a given vehicle speed are calculated. Details of operation 204 are described below. Figure 3 As described in the description.

[0034] exist Figure 2In operation 206, the environmental conditions of the given vehicle during actual operation are determined. Actual environmental conditions may include, for example, values ​​of one or more of the effective wind speed and effective wind angle encountered by the vehicle during operation. Data regarding actual environmental conditions may be determined by one or more sensors 128 mounted on vehicle 102, and / or may be provided by a telematics system, such as... Figure 2 As shown in the example in operation 206.

[0035] exist Figure 2 Operation 208 utilizes the fan power demand and aerodynamic power demand values ​​found in operation 204, as well as the environmental condition values ​​found in operation 206. These values ​​can be derived from data tables edited and stored in operations 202 and 204, and from sensor or telematics data inputs obtained from operation 206. Operation 208 involves determining and selecting the fan speed based on the power demand and environmental condition values. Calculation details in this operation 208 are described below. Figure 3 Explanation. By consulting the edited data table to determine the fan speed at which the sum of the fan power requirement and aerodynamic power requirement is reduced or preferably minimized for a given operating condition, such as the effective yaw angle shown in operation 208, the fan speed can be selected. At operation 210, the fan speed is controlled to the selected speed that reduces or minimizes the sum.

[0036] In actual vehicle operation, adjusting to... Figure 2 The controlled speed of the fan selected at operation 210 increases the fan speed to meet the vehicle's needs, such as reducing the cooling requirements when the temperature of components of the vehicle's prime mover (e.g., the intake manifold) exceeds a threshold. Figure 3 An embodiment of a system or method is shown, which includes determining an optimized fan speed in process 300 consistent with process 200, and further includes adjusting the controlled fan speed based on given operating parameters or vehicle requirements such as the need to cool vehicle components.

[0037] Figure 3 Process 300 begins with operation 302, to begin selecting the fan speed to optimize aerodynamic drag. At operation 304, according to the above regarding... Figure 2 As described in operation 202, the method includes calculating the aerodynamic drag (C0) of a given vehicle under a series of given operating conditions using a three-dimensional computational flow dynamics modeling method. dStep A) to determine the value. For example, in operation 202, to edit the data value, a series of tests are performed in operation 304, where the fan is controlled under a series of set fan speeds and set operating conditions. In the example depicted in operation 304, the given operating conditions include a series of set wind angles of 0 degrees, 6 degrees, 12 degrees, 18 degrees, and 24 degrees, which can be measured relative to the direction of forward movement of the vehicle or relative to the longitudinal axis of the vehicle 102. Tests can be performed at speeds set to 0 rpm, 100 rpm, 200 rpm, 300 rpm, 400 rpm, 500 rpm, and 600 rpm. The resulting dataset can be stored and used by the computer system of modeling system 130 and / or control system 104 in additional calculations and determinations, including creating tables related to fan speeds, which represent aerodynamic drag characteristic values ​​C for each specific brand, model, and year of vehicle under a set of operating conditions. d Data for A.

[0038] Figure 3 Operation 306 includes determining the fan power requirement (P) at a given fan rotation (operation) speed. fan The rated fan power requirement (P) of a given fan operating at a given fan operating speed. rated (These can be obtained from the respective fan manufacturers.)

[0039] At operation 308, the ambient atmospheric density under actual vehicle operating conditions can be determined or estimated to provide corrections for fan power requirements and vehicle aerodynamic requirements. The ambient density can be determined or estimated based on data provided by the vehicle's sensors and / or data obtained from a telematics system communicating with the vehicle's controller.

[0040] At operation 310, the vehicle speed, wind speed at the vehicle's operating position, and the wind angle encountered by the vehicle at the operating position are determined or estimated. These conditions can be determined or estimated based on data provided by the vehicle's sensors, vehicle operating settings, and / or data obtained from a telematics system communicating with the vehicle's controller.

[0041] At operation 312, the sum of the vehicle's aerodynamic power requirements and fan power requirements under actual operating conditions is calculated. The calculation includes estimating or determining the corrected fan power requirement value (P) under operating conditions. fan Rated fan power requirement (P) at a given rated fan speed. rated The following formula can be used to correct the ambient density based on the actual vehicle operating conditions and the actual fan operating speed:

[0042] P fan =P ratedx(Fan operating speed / Fan rated speed) 3 x(density under operating conditions / density under fan supplier test conditions)

[0043] Operation 312 also includes calculating the aerodynamic demand value P of the vehicle under operating conditions. aero The calculation is utilized in operation 304 (similar to...). Figure 2 The aerodynamic drag characteristic value C generated by operation 202) and preferably stored in memory in tabular form for reference by operation 312. d A. The table can be consulted to determine the value based on a given vehicle model / brand / year under actual wind conditions.

[0044] P aero = 1 / 2 x density under operating conditions * C d A*V 3

[0045] in:

[0046] P aero Power required to overcome aerodynamic drag (kW)

[0047] Density: Ambient density under actual vehicle operating conditions (kg / m³) 3 )

[0048] Cd: Dimensionless drag coefficient of the vehicle

[0049] A: Front area of ​​the vehicle (m²) 2 )

[0050] V: Air speed relative to the vehicle (m / s)

[0051] At operation 314, select the fan speed, and at the fan speed P aero +P fan The sum decreases. Preferably, a fan speed is selected at which P... aero +P fan Minimize the sum.

[0052] At operation 316, an operation can be performed to begin adjusting the controlled speed of the fan selected at operation 314, thereby controlling the fan speed to meet the vehicle's needs. For example, it may be necessary to increase the fan speed to reduce the temperature of vehicle components, such as the intake manifold of the vehicle's prime mover experiencing temperatures exceeding a set threshold. At operation 318, parameters of the vehicle's components can be sensed. For example, the operating temperature of the components can be sensed, determined, or estimated, and the temperature values ​​can be recorded. For example, in the case of a diesel engine's prime mover, the coolant temperature and / or intake manifold temperature can be determined.

[0053] At operation 320, one or more of the determined component parameters (e.g., temperature) can be compared with corresponding reference parameters (e.g., temperatures from a reference table stored in the memory of the control system 104). The reference temperatures in the table correspond to a predetermined setting of the fan speed based on the prime mover's calibration settings, and a predetermined fan speed setting is determined. At operation 322, the predetermined fan speed setting based on the reference temperature is compared with the fan speed selected at operation 314 to optimize aerodynamic drag reduction. The higher of the two fan speeds is selected as the chosen fan speed, and the fan is controlled by the control system to operate at the selected fan speed, resulting in the process 300 ending at end operation 324.

[0054] exist Figure 4 Another illustrative embodiment of the method is schematically shown in the flowchart. This embodiment uses optimized selection of fan speed to reduce overall vehicle power demand (e.g., fuel refueling requirements in the case of a diesel engine) based on iterative adjustments of fan speed during actual vehicle operation. Data on the vehicle's fuel refueling requirements associated with a specific fan speed are used to select an optimized fan speed at which overall power demand is reduced or minimized. This can be based on an optimized fan speed for minimum power demand, or on a method described above. Figure 3 The fan speed is selected to maintain the required operating temperature limit in a manner consistent with operations 316 to 320.

[0055] like Figure 4 As seen, the implementation of process 400 includes starting at operation 402 to determine the dynamic optimization of the vehicle's fan speed during actual operation to reduce overall vehicle power demand. For example, in Figure 3 In this process, the inventors' findings are implemented as follows: for a given vehicle under given operating conditions, an optimized fan speed can be determined at which a maximum reduction in aerodynamic drag can be achieved relative to the given vehicle 102, thereby minimizing fuel refueling requirements while maintaining all other parameters in a stable state. The process may include adjusting a selected fan speed to maintain vehicle operating requirements, such as cooling needs.

[0056] At operation 404, process 400 includes the step of calculating the vehicle's fuel refueling requirement or fuel refueling demand. The fuel refueling requirement can be determined or estimated as the mass of fuel (m³) consumed per unit time by the prime mover to meet a given set of operating parameters or demands of the vehicle. f (t)). Operating parameters may include a set vehicle speed requirement controlled by the vehicle operator, which needs to overcome the driving force. At operation 406, the fan speed N is initialized. fThe steps are as follows. For example, the initial fan speed N1 can be set to 100 rpm. At operation 408, the fuel filling requirement m experienced by the fan speed set at the initial speed N1 is measured. f The steps of (t).

[0057] At operation 410, the step of changing the fan speed is performed. This initiates a series of iterations in which other relevant vehicle operating parameters remain stable, while the fan is controlled to operate at a range of different set speeds, thereby allowing measurement of the impact of fan speed changes on fuel filling requirements m. f The effect of (t). For example, keeping all other operating parameters at a steady state, reducing the fan speed by 10 rpm, as shown in the repeated iterations from operation 410 to operation 406 (see arrow), allows the effect of the fan speed change on the fuel filling requirement m to be measured. f The effect of (t). At step 406, the fan speed is adjusted as a new iteration N2, and the fuel requirement is measured again at step 408. Through steps 406 to 410, the wheels N1 to N... x The repeated loops generate a dataset that can be recorded and stored, displaying fuel refueling requirements that vary based on fan speed. A reference to a table containing this edited data allows for the selection of an optimized fan speed based on real-time optimization. The reference dataset provides a framework for achieving maximum reduction in fuel refueling requirements. f The optimal fan speed is identified (t), while all other operating parameters remain stable. The optimized fan speed is selected at operation 412.

[0058] At operations 414 to 418, similar to Figure 3 The process, shown in operations 316 to 320 and described in detail above, allows for optional steps to adjust the optimized fan speed to meet specific vehicle operating requirements. At operation 414, an operation can be performed to begin adjusting the controlled speed of the fan selected at operation 412, thereby increasing the fan speed to meet the vehicle's needs. For example, the need might be to reduce the temperature of vehicle components. In the example shown in operation 416, the operating temperature of the component can be sensed, determined, or estimated, and the temperature value can be recorded. At operation 418, the determined component temperature can be compared with a corresponding reference temperature from a reference table stored in the memory of the control system 104. The reference temperatures in the table correspond to a predetermined setting of the fan speed based on the prime mover's calibration settings, and a predetermined fan speed is selected. At operation 420, the predetermined fan speed setting based on the reference temperature is compared with the fan speed selected at operation 412 to optimize aerodynamic drag reduction. The higher of the two fan speeds is selected as the chosen fan speed, and the fan is controlled by the control system 104 to operate at the selected fan speed, resulting in the process 400 ending at end operation 422.

[0059] Figure 5 This illustrates the drag reduction level (C) determined by the optimized modeling procedure established herein, as discovered by the inventors, within the fan speed range (0-600 rpm). d A[m 2 Example data for ]). Figure 6A and Figure 6B This illustrates exemplary results achieved by using fan speed optimization to reduce drag, thereby enabling a lower vehicle power demand to maintain a given vehicle speed. Figure 6A This indicates that, in a given vehicle setting operating at 50 mph, optimized fan speed at approximately 350 rpm resulted in a 1.2 hp reduction in the power required to maintain that speed. Figure 6B The report states that, in a given vehicle setting operating at 65 mph, the optimized fan speed at approximately 400 rpm resulted in a 2.9 hp reduction in power required to maintain the 65 mph vehicle speed compared to the power required at zero fan speed.

[0060] Regarding the construction of the vehicle and equipment disclosed herein, it should be understood that the powertrain of vehicle 102 is an exemplary construction, and other embodiments contemplate other powertrain constructions, including, for example, hybrid powertrain constructions, and other torque transmission devices, such as torque converters, gear separators, differentials, deep reduction gears and / or other devices, may be included in the torque path between prime mover 106 and drive wheels 110 of vehicle 102.

[0061] Vehicle 102 can have various configurations, such as a tractor-trailer truck configuration. The truck can have a conventional American cab layout or an engine-mounted cab layout (e.g., a conventional European or Chinese layout).

[0062] The control system 104 may be operatively coupled and configured to store instructions in memory, which can be read and executed by the control system 104 to operate the fan 120 or other components of the vehicle. It should be understood that the control system 104, or the control module performing the control functions as described herein, may be provided in various forms and configurations, including one or more computing devices forming an integral or partial processing subsystem having non-transitory memory storing computer-executable instructions, processing hardware, and communication hardware. The control system 104 may be a single device or a distributed device, and the functions of the control system 104 may be executed by hardware or by instructions encoded on a computer-readable medium.

[0063] Control system 104 includes stored data values, constants, and functions, as well as operating instructions stored on a computer-readable medium. Any operation of the exemplary process described herein can be performed at least in part by control system 104. Other groups performing similar overall operations are understood to be within the scope of this application. Modules may be implemented in hardware and / or software on one or more computer-readable media, and modules may be distributed across various hardware or software components. Figures 2 to 4 The operations described herein are a more specific description of certain embodiments of the operation of the control system 104. The operations shown are to be understood as merely exemplary, and operations may be combined or divided, added or removed, and reordered wholly or partially.

[0064] Some of the operations described herein include the interpretation or determination of one or more data points or parameters. As used herein, interpretation or determination includes receiving values ​​by any method, including receiving values ​​from at least a data link or network communication, receiving an electronic signal indicating the value (e.g., a voltage, frequency, current, or pulse width modulation (PWM) signal), receiving a software parameter indicating the value, reading a value from a memory location on a computer-readable medium, receiving a value as a runtime parameter by any means known in the art, and / or by receiving a value of a parameter that can be interpreted or determined by its calculation or estimation, and / or by referring to a default value interpreted or determined as a parameter value.

[0065] A method is disclosed, comprising: determining the aerodynamic drag characteristics of a vehicle in an operating state at multiple speeds of a vehicle's fan; determining the fan power demand at each of the multiple speeds; and controlling the fan speed to a controlled speed at which the sum of the vehicle's aerodynamic power demand and the fan power demand is reduced. For a given vehicle speed, the sum can be reduced to a minimum. Operating conditions may include wind angle, and the fan may be a cooling fan of the vehicle's prime mover. The method may include the step of adjusting the controlled speed of the fan based on vehicle operating parameters, and the operating parameters may be the vehicle's cooling demand.

[0066] A system is also disclosed, comprising: a vehicle, a fan, and a control system configured to receive input signals from the vehicle and provide output signals to control the fan speed. The control system may be configured to perform the following actions: determine the aerodynamic drag characteristics of the vehicle in operating states at multiple fan speeds; determine the fan power demand at each of the multiple speeds; and control the fan speed to a controlled speed at which the sum of the vehicle's aerodynamic power demand and the fan power demand is reduced. For a given vehicle speed, the sum can be reduced to a minimum. Operating conditions may include wind angle, and the fan may be a cooling fan of the vehicle's prime mover.

[0067] A method is also disclosed, the method comprising: operating a vehicle having a fan and a control system, the control system being operatively communicateable with the vehicle and the fan to perform the following actions: repeatedly changing the rotational speed of the fan during operation of the vehicle under operating parameters; determining a fuel consumption value of the vehicle associated with the changed rotational speed; predicting a future fuel consumption value under the operating parameters using the determined fuel consumption value; selecting a rotational speed of the fan at which the predicted future fuel consumption value decreases under the operating parameters; and controlling the fan to operate at the selected rotational speed during operation of the vehicle under the operating parameters. The operating parameters may include vehicle speed. The fan may be a cooling fan of the vehicle's prime mover. The method may include the step of adjusting a controlled speed of the fan based on a second operating parameter, and the second operating parameter may be the vehicle's cooling requirements.

[0068] A system is also disclosed, comprising: a vehicle, a fan, and a control system configured to receive input signals from the vehicle and provide output signals to control the vehicle and the fan. The control system may be configured to perform the following actions: repeatedly changing the fan speed during vehicle operation under operating parameters; determining a fuel consumption value of the vehicle associated with the changed speed; predicting future fuel consumption values ​​under the operating parameters using the determined fuel consumption value; selecting a fan speed at which the predicted future fuel consumption value decreases under the operating parameters; and controlling the fan to operate at the selected speed during vehicle operation under the operating parameters. The operating parameters may be vehicle speed, and the fan may be a cooling fan of the vehicle's prime mover. The control system may adjust the controlled speed of the fan based on the cooling requirements of the prime mover.

[0069] Also disclosed is an apparatus comprising: a vehicle, a fan, and a control system, the control system being configured to receive an input signal from the vehicle and provide an output signal to control the fan speed, the control system being configured to perform the following actions: repeatedly changing the fan speed during operation of the vehicle under operating parameters; determining a fuel consumption value of the vehicle associated with the changed speed; predicting a future fuel consumption value under the operating parameters using the determined fuel consumption value; selecting a fan speed at which the predicted future fuel consumption value decreases under the operating parameters; and controlling the fan to operate at the selected speed during operation of the vehicle under the operating parameters.

[0070] Those skilled in the art will understand from the foregoing the unexpected benefits derived from the application of methods, systems, and apparatuses addressing the problem of improving fuel efficiency in operating conventional vehicles without requiring additional components or parts or altering the construction of the conventional vehicle or its features. Additional components and parts may increase the weight of the vehicle, thereby reducing fuel efficiency. Altering the construction of a conventional vehicle may increase the cost and complexity of its manufacture, operation, and maintenance. A key benefit envisioned by the inventors is the improvement of fuel efficiency in conventional vehicles by using the disclosed dynamic fan speed control optimization system, method, or apparatus, while eliminating any changes to additional components, steps, or structural features. In this elimination, maximum cost control can be achieved. Therefore, the substantial benefit of the simplicity in manufacturing, operating, and maintaining standard or conventionally produced vehicles to which the methods and systems described herein can be applied may exist in embodiments of the invention that are comprised or substantially composed of the methods, systems, or apparatuses disclosed herein. Therefore, embodiments of the invention contemplate excluding those steps, features, parts, and components beyond those described herein. In some embodiments, the inventors contemplate excluding certain steps, features, parts, and components set forth in this disclosure, even if such steps, features, parts, and components are considered preferred or more desirable.

[0071] Although the invention has been illustrated and described in detail in the accompanying drawings and the foregoing description, the illustrations and descriptions should be regarded as illustrative rather than restrictive. It should be understood that only certain exemplary embodiments have been shown and described, and it is intended to protect all variations and modifications that fall within the spirit of the invention.

Claims

1. A method for controlling fan speed, the method comprising: operating a vehicle, the vehicle having a fan and a control system in operable communication with the vehicle and the fan to perform the following acts: repeatedly varying the speed of the fan during operation of the vehicle at an operating parameter to vary the aerodynamic drag of the vehicle; determining a fuel consumption value of the vehicle associated with the varied speed and the varied aerodynamic drag; using the determined fuel consumption value to predict a future fuel consumption value at the operating parameter; selecting a speed of the fan at which the predicted future fuel consumption value decreases at the operating parameter; and controlling the fan to operate at the selected speed during operation of the vehicle at the operating parameter.

2. The method of claim 1, wherein the operating parameter comprises vehicle speed.

3. The method of claim 1, wherein the fan comprises a cooling fan of a prime mover of the vehicle.

4. The method of claim 1, further comprising: adjusting the controlled speed of the fan based on a second operating parameter.

5. The method of claim 4, wherein the second operating parameter comprises a cooling demand of the vehicle.

6. A system for controlling fan speed, the system comprising: a vehicle, a fan, and a control system configured to receive input signals from the vehicle and provide output signals to control the vehicle and the fan, the control system configured to perform the following acts: repeatedly varying the speed of the fan during operation of the vehicle at an operating parameter to vary the aerodynamic drag of the vehicle; determining a fuel consumption value of the vehicle associated with the varied speed and the varied aerodynamic drag; using the determined fuel consumption value to predict a future fuel consumption value at the operating parameter; selecting a speed of the fan at which the predicted future fuel consumption value decreases at the operating parameter; and controlling the fan to operate at the selected speed during operation of the vehicle at the operating parameter.

7. The system of claim 6, wherein the operating parameter comprises vehicle speed.

8. The system of claim 6, wherein the fan is a cooling fan of a prime mover of the vehicle.

9. The system of claim 6, wherein the control system adjusts the controlled speed of the fan based on a cooling demand of the prime mover of the vehicle.

10. An apparatus for fan speed control, the apparatus comprising: a vehicle, a fan, and a control system configured to receive input signals from the vehicle and provide output signals to control fan speed, the control system configured to perform the following acts: repeatedly varying the speed of the fan during operation of the vehicle at an operating parameter to vary the aerodynamic drag of the vehicle; determining a fuel consumption value of the vehicle associated with the varied speed and the varied aerodynamic drag; using the determined fuel consumption value to predict a future fuel consumption value at the operating parameter; selecting a speed of the fan at which the predicted future fuel consumption value decreases at the operating parameter; and ​ selecting a rotational speed of the fan at which a predicted future fuel consumption value is reduced at the operating parameter; and controlling the fan to operate at the selected rotational speed during operation of the vehicle at the operating parameter.

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