Temperature Control Using Active Flow Control Actuators

Abstract

The synthetic jet actuator includes a cavity layer having an internal cavity for receiving a fluid volume and an orifice providing fluid communication between the cavity and the ambient atmosphere, a vibrating membrane having a piezoelectric material adapted to deflect the vibrating membrane in response to an electronic signal, and a controller configured to control delivery of the electronic signal to the piezoelectric material to control operation of the vibrating membrane based on input data received from one or more sources indicating the temperature and / or performance level of the object targeted for cooling. The actuator further includes a thermal element for affecting the modified temperature control, and the actuator may be integrated into a surface of a heat-dissipating structure to dissipate heat from a thermal load.

Description

[Technical field]

[0001] SYNTHETIC JET ACTUATOR AND METHODS OF TEMPERATURE CONTROL USING SAME FIELD OF THE DISCLOSURE The present invention is directed to improvements in synthetic jet actuators suitable for temperature control in zero net mass flow applications. [Background technology]

[0002] Vehicles use cooling systems, such as forced convection, liquid cooling, and mechanical fans, to remove excess heat from the battery and avoid failures, however, conventional cooling systems suffer from several drawbacks.

[0003] Traditional cooling systems cannot respond to time and location specific cooling needs, or provide "localized cooling," reducing the risk of localized failure; traditional systems that use conductive masses such as large aluminum heat sinks and forced air cooling are heavy, expensive, and occupy large volumes in areas where space is already at a premium. At the same time, traditional mechanical cooling systems, such as fans, have many moving parts with no electrical infrastructure to provide performance data, which prevents communications that could provide advanced warning alerts and provide predictive maintenance prior to potential failure.

[0004] Traditional cooling methods such as forced convection also present limitations, for example, because many modern vehicles are designed to reduce air resistance to achieve greater energy efficiency and increased range. These designs, which deflect airflow as the vehicle moves, minimize the passage of air through the vehicle's exterior surfaces and into interior systems, such as the engine, for which forced convection cooling is required. As a result, many modern vehicles are designed to effectively "seal" their interiors from exterior airflow, thereby reducing the opportunity for interior electronics and electronic systems (such as the battery and electronic control unit (ECU)) to be cooled via forced air convection, and instead require other cooling systems.

[0005] Conventional cooling systems also cannot instantly and autonomously adapt to changes in thermal conditions and vehicle performance. For example, mechanical fans do not provide sufficient control to respond to the wide variety of thermal conditions that may be generated throughout different driving scenarios (e.g., urban vs. highway driving environments and conditions), terrains, and seasons as the vehicle operates.

[0006] Conventional cooling systems often also require additional resources and equipment, such as coolant, liquid reservoirs, and piping, pumps, and other equipment for liquid cooling, with an additional reliance on airflow openings to the outside environment in systems employing forced air convection. Reliance on these additional resources reduces vehicle performance, such as aerodynamics, weight, etc.

[0007] Thus, there remains a need for improvements to cooling systems, and temperature control systems in general. Summary of the Invention [Means for solving the problem]

[0008] The synthetic jet actuator includes a cavity layer having an internal cavity for receiving a quantity of fluid and an orifice providing fluid communication between the cavity and an outside atmosphere, a vibrating membrane having a piezoelectric material adapted to deflect the vibrating membrane in response to an electronic signal, and a controller configured to control delivery of the electronic signal to the piezoelectric material to control movement of the vibrating membrane.

[0009] The cavity has an opening in the planar surface of the cavity layer, and the vibratory membrane is positioned adjacent to the planar surface having the cavity opening and adapted as an encapsulating surface for the cavity opening. The vibratory membrane is adapted to compress and expand a volume within the cavity to generate a fluid flow between the cavity and the outside air through the orifice based on a deflection generated by the piezoelectric material, and the controller is configured to receive input data informing of a need for temperature control of the targeted object to control the operation of the vibratory membrane under at least one predetermined parameter and to control delivery of an electronic signal to the piezoelectric material to affect temperature control of the targeted object.

[0010] The controller is configured to receive input data indicative of an approximate temperature or temperature range of the targeted object, and to use the input data to determine at least one parameter for influencing temperature control to achieve a target temperature or target temperature range of the targeted object. The controller is also configured to receive input data indicative of a performance level of the targeted object, and to use the input data to determine at least one parameter for influencing temperature control to achieve a target performance level of the targeted object. The controller is configured to control operation of the vibrating membrane under at least one predetermined parameter selected from frequency, amplitude, waveform, phase, duty cycle, and modulation frequency, and is configured to control operation of the vibrating membrane to modify the at least one predetermined parameter as necessary to achieve the target temperature and / or target performance level.

[0011] In some examples, the synthetic jet actuator is provided within a vehicle, and the controller is configured to receive input data from at least one on-board vehicle source and / or at least one source external to the vehicle. Non-limiting examples of on-board vehicle sources include a vehicle electronic control unit (ECU), a data management platform (DMP) of a vehicle cooling system, and a DMP of a targeted object. Non-limiting examples of sources external to the vehicle include vehicle-to-vehicle (V2V) communications in another vehicle or mobile platform, one or more transmitters in a network of autonomous vehicles, and a control center coordinating multiple mobile platforms.

[0012] In some examples, the synthetic jet actuator further comprises a thermal element provided in the cavity of the cavity layer, the thermal element may be in the form of a thermal element comprising a heating coil, the controller being configured to control a temperature of the thermal element by controlling power supplied to the heating coil to modify the temperature of the cavity and enable temperature control of the fluid flow exhausted from the cavity to the outside air.

[0013] In such an example, the controller is configured, upon receiving input data indicative of a need for temperature control of the targeted object, to activate and control delivery of electronic signals to the piezoelectric material to operate the vibrating membrane and affect temperature control of the targeted object, and determine whether there is a need to affect modified temperature control of the targeted object to achieve greater heat transfer than is possible from operation of the vibrating membrane alone. If a determination is made that modified temperature control is required, the controller activates the thermal element to control its temperature while continuing to control operation of the vibrating membrane and affect modified temperature management of the targeted object, and if a determination is made that modified temperature control is not required, the controller continues operation of the vibrating membrane without operation of the thermal element to affect temperature control of the targeted object.

[0014] Following activation of the thermal element to affect the modified temperature control, the controller determines whether the targeted object has reached thermal equilibrium to achieve the target temperature or target performance level. If a determination is made that the targeted object has reached thermal equilibrium, the controller deactivates the thermal element and discontinues the modified temperature control of the targeted object, and if a determination is made that the targeted object has not reached thermal equilibrium, the controller maintains operation of the thermal element for continued modified temperature control of the targeted object.

[0015] Following deactivation of the thermal element to terminate the modified temperature control of the targeted object, the controller determines whether thermal equilibrium of the targeted object is maintained. If a determination is made that thermal equilibrium is not maintained, the controller continues to control operation of the vibrating membrane and reactivates the thermal element to control its temperature while updating the modified temperature control of the targeted object, and if a determination is made that thermal equilibrium is maintained, the controller deactivates operation of the vibrating membrane and discontinues temperature control of the targeted object.

[0016] In some other examples, the synthetic jet actuator may be integrated into a surface of a heat-dissipating structure to dissipate heat from a thermal load. For example, the synthetic jet actuator may be integrated into a vane of a heat sink. In such examples, the vane is configured as a cavity layer of the synthetic jet actuator, with a cavity formed in the vane having a cavity opening formed in a planar surface of the vane, an orifice formed in an exterior surface of the vane that provides fluid communication between the cavity and the outside atmosphere, and a vibrating membrane positioned adjacent to the planar surface of the vane having the cavity opening and adapted as an encapsulating surface for the cavity opening.

[0017] Multiple synthetic jet actuators may be integrated into the surface of such a thermally dissipative structure, powered by a common power source, and controlled by a common controller, In such an example, the controller may be configured to enable control of individual synthetic jet actuators under custom operating parameters based on the location of the synthetic jet actuators in the structure and the thermal load at the location of the synthetic jet actuators.

[0018] Both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the invention as claimed. The accompanying drawings are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention. The present invention provides, for example, the following: (Item 1) A synthetic jet actuator, comprising: a cavity layer having an internal cavity for receiving a quantity of fluid and an orifice providing fluid communication between the cavity and the outside atmosphere; a vibratory membrane comprising a piezoelectric material adapted to deflect the vibratory membrane in response to an electronic signal; a controller configured to control delivery of electronic signals to the piezoelectric material to control movement of the vibrating membrane; Equipped with the cavity has an opening in a planar surface of the cavity layer, the vibratory membrane being positioned adjacent to the planar surface having the cavity opening and adapted as an encapsulating surface for the cavity opening; the vibrating membrane is adapted to compress and expand a volume within the cavity based on a deflection generated by the piezoelectric material to generate a fluid flow between the cavity and the outside air through the orifice; The synthetic jet actuator, wherein the controller is further configured to receive input data indicative of a need for temperature control of a targeted object, and control delivery of the electronic signal to the piezoelectric material to control movement of the vibrating membrane under at least one predetermined parameter to affect temperature control of the targeted object. (Item 2) 2. The synthetic jet actuator of claim 1, wherein the controller is configured to receive input data indicative of an approximate temperature or temperature range of the targeted object, and to use the input data to determine at least one parameter for affecting temperature control to achieve a target temperature or target temperature range of the targeted object. (Item 3) 2. The synthetic jet actuator of claim 1, wherein the controller is configured to receive input data indicative of a performance level of the targeted object, and to use the input data to determine at least one parameter for affecting temperature control to achieve a target performance level of the targeted object. (Item 4) 2. The synthetic jet actuator of claim 1, wherein the controller is configured to control the movement of the vibrating membrane under at least one predetermined parameter selected from frequency, amplitude, waveform, phase, duty cycle, and modulation frequency. (Item 5) 5. The synthetic jet actuator of claim 4, wherein the controller is configured to control operation of the vibrating membrane to modify the at least one predetermined parameter as needed to achieve a target temperature and / or a target performance level. (Item 6) The synthetic jet actuator is provided within a vehicle; 2. The synthetic jet actuator of claim 1, wherein the controller is configured to receive input data from at least one on-board vehicle source. (Item 7) 7. The synthetic jet actuator of claim 6, wherein the controller is configured to receive input data from at least one on-board vehicle source selected from a vehicle electronic control unit (ECU), a vehicle cooling system data management platform (DMP), and a DMP of the targeted object. (Item 8) The synthetic jet actuator is provided within a vehicle; 2. The synthetic jet actuator of claim 1, wherein the controller is configured to receive input data from at least one source external to the vehicle. (Item 9) The synthetic jet actuator of item 8, wherein the controller is configured to receive input data from at least one source external to the vehicle selected from vehicle-to-vehicle (V2V) communication in another vehicle or moving platform, one or more transmitters in a network of autonomous vehicles, and a control center coordinating multiple moving platforms. (Item 10) a thermal element provided in the cavity of the cavity layer; 2. The synthetic jet actuator of claim 1, wherein the controller is further configured to control a temperature of the thermal element to modify a temperature of the cavity to enable temperature control of a fluid flow exhausted from the cavity to the outside air. (Item 11) the controller is further configured to, upon receiving input data indicative of a need for temperature control of the targeted object, activate and control delivery of the electronic signal to the piezoelectric material to operate the vibrating membrane and affect temperature control of the targeted object; the controller is further configured to determine whether there is a need to affect a modified temperature control of the targeted object to achieve a greater heat transfer than is possible from operation of the vibrating membrane alone; The controller: if a determination is made that modified temperature control is required, activating the thermal element and controlling its temperature while continuing to control the movement of the vibrating membrane to affect modified thermal management of the targeted object; and if a determination is made that modified temperature control is not required, continuing operation of the vibrating membrane without operation of the thermal element to affect temperature control of the targeted object. Item 11. The synthetic jet actuator of item 10, further configured to: (Item 12) the controller is further configured to determine whether the targeted object has reached thermal equilibrium to achieve a target temperature or a target performance level following activation of the thermal element to affect a modified temperature control; The controller: deactivating the thermal element and ceasing modified temperature control of the targeted object when a determination is made that the targeted object has reached thermal equilibrium; and maintaining operation of the thermal element for continued corrective temperature control of the targeted object if a determination is made that the targeted object has not reached thermal equilibrium. Item 12. The synthetic jet actuator of item 11, further configured to: (Item 13) the controller is further configured to determine whether thermal equilibrium of the targeted object is maintained following deactivation of the thermal element to cease modified temperature control of the targeted object; The controller: if a determination is made that thermal equilibrium is not being maintained, reactivating the thermal element and controlling its temperature while continuing to control the movement of the vibrating membrane and updating a revised temperature control of the targeted object; and if a determination is made that thermal equilibrium is maintained, then ceasing operation of said vibrating membrane and ceasing temperature control of said targeted object. Item 13. The synthetic jet actuator of item 12, further configured to: (Item 14) Item 11. The synthetic jet actuator of item 10, wherein the thermal element comprises a heating coil, and the controller is configured to control the temperature of the thermal element by controlling power supplied to the heating coil. (Item 15) 1. A thermally dissipative structure for dissipating heat from a thermal load, the thermally dissipative structure comprising: 2. A heat spreading structure comprising the synthetic jet actuator of claim 1 integrated into a surface of the heat spreading structure. (Item 16) Item 16. The heat spreading structure of item 15, wherein the heat spreading structure is a heat sink and the synthetic jet actuator is integrated into the vanes of the heat sink. (Item 17) the vanes of the heat sink are configured as the cavity layer of the synthetic jet actuator, the cavity layer having the cavities formed in the vanes with the cavity openings formed in a planar surface of the vanes and orifices formed in an exterior surface of the vanes for providing fluid communication between the cavities and the outside air; Item 17. The heat spreading structure of item 16, wherein the vibrating membrane is positioned adjacent to the planar surface of the vane having the cavity opening and adapted as an encapsulating surface for the cavity opening. (Item 18) Item 16. The heat spreading structure of item 15, wherein multiple synthetic jet actuators are integrated into a common vane of the heat sink. (Item 19) 20. The heat spreading structure of claim 18, wherein the multiple synthetic jet actuators are powered by a common power source and controlled by a common controller. (Item 20) 20. The thermal diffusive structure of item 19, wherein the controller is configured to enable control of individual synthetic jet actuators under custom operating parameters based on the position of the synthetic jet actuator on the heat sink and the thermal load at the location of the synthetic jet actuator. [Brief description of the drawings]

[0019] Further features and advantages of the present invention can be ascertained from the following detailed description, provided in conjunction with the drawings in which: [Figure 1] FIG. 1 shows an example of an actuator according to the present invention.

[0020] [Diagram 2] FIG. 2 shows an exploded view of the actuator of FIG.

[0021] [Diagram 3] FIG. 3 shows an exploded view of the vibratory membrane of FIG.

[0022] [Figure 4] FIG. 4 illustrates operating states of the actuator of FIG. 1, including an expanded space operating state (top) and a contracted cavity operating state (bottom).

[0023] [Diagram 5] FIG. 5 shows the actuator of FIG. 1 with a thermal element within its cavity.

[0024] [Figure 6] FIG. 6 illustrates a process of temperature control using the actuator of FIG.

[0025] [Figure 7] FIG. 7 shows the assembly of a heat sink, in which the actuator of FIG. 1 is integrated into the heat sink.

[0026] [Figure 8]FIG. 8 illustrates a process for temperature control using the assembly of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The following disclosure will discuss the invention with reference to examples illustrated in the accompanying drawings, without, however, limiting the invention to these examples.

[0028] The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended merely to better clarify the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential or otherwise required to the practice of the invention unless the context is clear.

[0029] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise. The term "or" is to be understood as an inclusive "or" unless the context dictates otherwise. The terms "first," "second," "third," etc., when used to describe multiple devices or elements, are so used only to convey the relative action, positioning, and / or functionality of the separate devices and do not require a particular order to such devices or elements or any particular quantity or ranking of such devices or elements.

[0030] The word "substantially," as used herein with respect to any property or circumstance, refers to a degree of deviation that is small enough so as not to materially impair the identified property or circumstance. The exact degree of deviation that is permissible in a given situation will depend on the particular context, as will be understood by those of ordinary skill in the art.

[0031] Use of the term "about" or "approximately" is intended to describe values ​​above and / or below a stated value or range, as would be understood by one of skill in the art in each context. In some cases, it includes values ​​in a range of about + / - 10%, in other cases, it includes values ​​in a range of about + / - 5%, in still other cases, it includes values ​​in a range of about + / - 2%, and in still further cases, it includes values ​​in a range of about + / - 1%.

[0032] The terms "comprises" and / or "comprising", as used herein, unless otherwise indicated herein or clearly contradicted by context, should be understood to specify the presence of stated features, integers, steps, operations, elements, and / or components, but not to preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0033] The recitation of ranges of values ​​herein, unless otherwise indicated, serves as a shorthand notation for referring individually to each separate value falling within the stated range, including the endpoints of that range, each separate value within that range, and all intermediate ranges encompassed by the entire range, each value being incorporated herein as if it were individually listed herein.

[0034] Unless otherwise indicated or clearly contradicted by context, methods described within this specification can be performed with individual steps carried out in any suitable order, including the exact order as disclosed, without any intermediate steps intervening between the disclosed steps, or with one or more intervening steps, the disclosed steps being performed in an order other than the exact order as disclosed, one or more steps being performed simultaneously, and one or more disclosed steps being excluded.

[0035] The present invention includes systems and methods for cooling electrical systems (e.g., LIBs) in vehicles using one or more individual actuators or arrays of actuators mounted on the vehicle surface or directly on the electrical system of interest (e.g., inside or outside a battery pack or heat sink). In cases where an actuator array is used, the array can be controlled to dynamically adapt to the spatial heat distribution within the targeted electrical system, and the individual actuators can be controlled by one or more controllers, ECUs, microprocessors, computers, sensors using feedback loops, and combinations thereof.

[0036] One application envisioned by the present invention is the cooling of electrical systems such as LIB modules and / or single LIB cells to avoid failures, degradation, and performance inefficiencies. As the demand for electric vehicles increases, not only the requirements for LIB performance but also the cooling requirements for such systems increase. The system and method according to the present invention can be used for LIB cooling alone or as a complement to improve existing cooling systems such as liquid and forced convection systems. A feedback loop can be used between the system control device and the battery management system to monitor the existing system and the status of the electrical system targeted for cooling, and the control device can control the actuators to maintain optimal performance of the electrical system and a balance between the use of the electrical system and real-time, dynamic, or predefined performance criteria of the vehicle.

[0037] The present invention includes a cooling system that integrates an active flow control (AFC) actuator, such as a synthetic jet actuator (SJA). The SJA may be integrated into the vehicle or into an electrical system targeted to cool the vehicle and may be used as an AFC actuator or any other type of actuator (suction blowing actuator, sweeping jet, fluid actuator, etc.). The actuator array may be integrated into areas that are heat sensitive and / or may fail as a result of excessive heat. The actuators are data driven, electrical (no fresh air or ducting required), and small enough in size to be integrated into and / or around the electrical system. Being data driven, the actuators receive input data to control their operation and performance (switching on / off states, changing frequency and waveform, etc.). Data is provided by controllers, diagnostic systems, electronic control unit (ECU) sensors, battery management systems, and other feedback loop components.

[0038] AFC actuators according to the invention may be connected in a feedback loop to an input provider through a data management unit, such as a controller, to control selective activation of actuators in an array with independent performance requirements. For example, the controller may control the drive frequency to be used based on a detected temperature range (such as in a system where different frequencies may affect air mixing differently depending on the ambient temperature).

[0039] By improving the cooling of electrical systems in land, sea or air vehicles, the systems and methods according to the present invention are expected to increase the overall performance, safety, functionality and energy efficiency of these vehicles.

[0040] FIG 1 shows one example of an AFC actuator 100 in accordance with the present invention, and FIG 2 shows an exploded view of the separate layers of the actuator 100. The actuator, such as the illustrated example, is electrically powered and electrically controlled for cooling of an electrical system in a vehicle or a vehicle subcomponent (e.g., a battery). Although FIG 1 shows only a single actuator 100 with a dedicated power source 126 and controller 127, it should be understood that a cooling system in accordance with the present invention may include one or more actuators for generating the jet of air and one or more power sources 126 and controllers 127 for powering and controlling the actuators.

[0041] As shown in FIG. 1-2, the actuator 100 comprises a cavity layer 110 sandwiched between two vibrating membrane layers 120a / 120b. The cavity layer 110 comprises a body having first and second planar surfaces, an outer periphery, and an inner periphery, the inner periphery defining a cavity 111 within the cavity layer 110. The cavity 111 is open on at least one of the two planar surfaces, and may be open on both planar surfaces. When placed adjacent to the opening, the vibrating membrane layer 120 serves as an enclosing surface over the opening to the cavity 111, thereby defining an enclosed space within the cavity 111 for holding a fluid volume. The cavity layer 111 further comprises an orifice 112, which provides an airflow path between the cavity 111 and the atmosphere outside the actuator 100 for intake of air into the cavity 111 and output of airflow from the cavity 111.

[0042] FIG. 3 shows an exploded view of the vibratory membrane 120, and it should be understood that in the example of FIG. 1-2, both vibratory membranes 120a / 120b have the same structure as shown in FIG. 3. As shown in the illustrated example, the vibratory membrane 120 comprises a substrate 121 integrally bonded to at least one piezoelectric disk 123 by an adhesive adhesive 122. In the illustrated example, the substrate is bonded to two separate piezoelectric disks 123 (one on the top surface and one on the bottom surface), but in other examples, only one of the two illustrated piezoelectric disks 123 may be present. The adhesive adhesive 122 may be formed by one or two part thermosetting resins such as, but not limited to, two part epoxy resin, one part methacrylate resin, or a low melting metal such as silver solder. In some examples, the adhesive adhesive 122 may be formed through a thermosetting film adhesive, or "prepreg". In some examples, the adhesive adhesive 122 may be conductive. The vibratory membrane 120 further includes an outer layer 124 that encapsulates and secures the several layers therein as a composite vibratory membrane.

[0043] In use, the piezoelectric disk 123 is operable through the provision of power from a power source 126 (FIG. 1) and control signals are provided from a controller 127 via electrical connection 125. The power and control signals cause the piezoelectric disk 123 to deform, and due to the integral coupling of the disk 123 with the substrate 121, the deformation of the disk 123 causes a corresponding deflection of the substrate 121 (i.e., the vibratory membrane 120 as a whole) in the same direction. As shown in FIG. 4, outward deformation of the vibratory membrane 120a / 120b away from the cavity layer 110 causes an expansion of the cavity 111 generating an inward airflow through the orifice 112, and inward deformation of the vibratory membrane 120a / 120b towards the cavity layer 110 causes a compression of the cavity 111 generating an outward airflow through the orifice 112.

[0044] 1-4 show an example of an actuator 100 in which the cavity 111 is in the form of a through hole with two openings (one opening in each of the opposing planar surfaces of the cavity layer 110) and two vibratory membranes 120a / 120b are positioned as encapsulating surfaces over the separate cavity openings, but actuators in accordance with the invention are not limited to this configuration. The invention also includes unimorph actuators in which the cavity 111 is in the form of a blind hole with only one opening in a single planar surface of the cavity layer 110 and a single vibratory membrane 120 is positioned as an encapsulating surface over the single cavity opening.

[0045] A cooling system according to the present invention may include one or more actuators 100, which may also include one or more types of actuators, including but not limited to synthetic jet actuators, acoustic excitation actuators, plasma actuators, electrically generated sweeping jet actuators, suction and vibratory blowing (SaOB) actuators, etc. The actuator operating parameters are controlled through software stored in local memory of the controller 127 and may include but are not limited to operating frequency, operating amplitude, waveform, phase, duty cycle, and modulation frequency. In cooling systems with more than one actuator, additional operating parameters may also be stored in the controller 127, such as the number of actuators and the sequence of actuator operation based on the characteristics (geometry, structure, electromechanical) and position of each actuator. The actuators 100 are powered by electrical power from one or more power supply units 126, which may include one or more power supply units inherent to the vehicle itself and / or one or more auxiliary power supply units separate from those used by the vehicle.

[0046] A single controller 127 may command various cooling system components through one or more programs stored in the local memory of the controller 127. The controller is also configured to receive input data informing the controller of the need for cooling of one or more electrical systems, and the controller commands one or more actuators 100 to operate under specific parameters for controlling the targeted electrical system, which may include one of several different pre-stored operating modes. The input data received at the controller 127 may include activation data informing the controller to activate an actuator for cooling of the targeted electrical system; temperature data informing the controller of an approximate temperature or temperature range of the targeted electrical system that the controller may use to determine appropriate parameters for affecting the cooling of the targeted electrical system; and deactivation data informing the controller to deactivate an actuator to stop cooling of the targeted electrical system. The input data received at the controller 127 may also include performance data providing information regarding the performance level of the targeted electrical system that the controller may use to determine appropriate parameters for affecting the cooling of the targeted electrical system.

[0047] The controller 127 may receive input data from a number of different sources, including, but not limited to, a vehicle electronic control unit (ECU) and / or its sensors; a data management platform (DMP) and / or monitoring sensors provided within the cooling system itself; and one or more electrical systems for which the cooling system is configured to cool (e.g., a battery and / or its components). For example, the controller 127 may receive input data from a vehicle ECU that informs the performance level of an electrical system targeted for cooling, such as a battery management system (BMS) (for the controller 127 to use in determining appropriate parameters for cooling the BMS). The controller 127 may also receive input data from the cooling system's DMP that informs the performance level of one or more actuators 100 within the cooling system (for the controller 127 to use in determining optimal operating parameters for each actuator 100).

[0048] Controller 127 may also receive input data from sources external to the cooling system (the vehicle as a whole). For example, a vehicle-to-vehicle (V2V) communication device may be used to transmit to controller 127 input data generated by another nearby vehicle or moving platform, data generated by a network of autonomous vehicles, and / or data generated by a control center coordinating multiple moving platforms.

[0049] The controller 127 may use the input data from one or more sources, or a combination of all of the aforementioned sources, to adapt the performance of one or more actuators to achieve any number of goals, including, but not limited to, cooling system performance, overall vehicle performance, environmental conditions and / or constraints, and passenger preferences. The controller 127 may also record the received input data in a storage device, which may be a memory integrated and fixed locally within the cooling system, or a removable memory separable from the cooling system. The input data may optionally be recorded along with a concurrent recording of system diagnostics and / or system input and output data; the controller 127 may also be configured to broadcast the received input data and system diagnostics and / or system input and output data for uploading to one or more external sources.

[0050] 5 shows an example of an actuator 100 with an integrated thermal element 113 positioned in a cavity 111 of the cavity layer 110. The thermal element 113 may extend along a bounding surface 111' of the cavity 111 or may be shallowly recessed below the bounding surface 111'. The inclusion of the thermal element 113 enables the actuator 100 to provide greater temperature control of the airflow generated by the actuator 100, and thus can affect greater temperature control of the targeted electrical system (e.g., LIB battery, ECU, LEDs, headlights, heat sink, etc.) with a temperature range beyond what would otherwise be possible.

[0051] Conventional actuators generate airflow jets that increase air mixing around a targeted object, thereby cooling the object and increasing the heat flux to remove heat from the surface of the targeted object into the surrounding air. Synthetic jet actuators are zero net mass flow (ZNMF) in that they generate a pulsed airflow jet by generating an inward airflow to draw air from the surrounding environment into the cavity 111 and then an outward airflow to expel the air from the cavity 111 as an airflow jet at the targeted location. Because ZNMF actuators rely on the surrounding air for the generation of the airflow jet, the temperature of the airflow jet is strongly affected (often with small deviations) by the temperature of the surrounding environment.

[0052] Including a thermal element 113 in the form of a heating element, such as an electric heating coil in communication with a power source 126, the controller 127 can heat the thermal element 113 by controlling the voltage and current of the power source 126 to selectively modify the temperature inside the cavity 111 of the actuator 100, and therefore the temperature of the airflow generated from the cavity 111.

[0053] 6 provides an example of a temperature control process 300 using an actuator 100 comprising a thermal element 113 in the form of a heating element. In this example, the actuator 100 is configured to affect temperature control of an electrical system or other target object, and the controller 127 is configured to receive input data providing information regarding the need for temperature control of the target object, for example, from a management system associated with the target object. Upon starting the cooling system (step S301), the controller 127 will periodically check the input data providing information regarding the target object diagnosis (step S302) and determine whether temperature control is required (step S303). If it is determined that temperature control is not required (step S303, "No"), the process will forgo activation of the actuator 100 and periodically check the input data providing information regarding the target object diagnosis (step S302) and again determine whether temperature control is required (step S303).

[0054] If it is determined that temperature control is required (step S303, "yes"), the controller 127 will activate the actuator 100 (step S304) to control the temperature of the target object by generating an airflow jet directed at the target object to affect its temperature modification. The controller 127 will then use the input data providing information regarding the diagnosis of the target object to determine whether additional temperature modification is required for the target object, which would require a hot airflow jet. If the controller 127 determines that additional temperature modification is not required (step S305, "no"), the controller will forgo activation of the thermal element 113 and subsequently determine whether the thermal equilibrium of the target object has been restored (step S306). If the controller 127 determines that the thermal equilibrium has been restored (step S306, "yes"), the controller 127 will deactivate the actuator 100 (step S311). If the controller 127 determines that thermal equilibrium has not yet been restored (step S306, "No"), the controller 127 will maintain activation of the actuator 100 (step S304) and periodically determine whether additional temperature correction requiring hot airflow injection is required (step S305) and whether thermal equilibrium of the target object has been restored (step S306).

[0055] If it is determined that additional temperature correction is required requiring a hot airflow jet (step S305, "Yes"), the controller 127 will activate the thermal element 113 by providing power and a waveform for heating the thermal element 113 (step S307), thereby heating the cavity 111 such that the actuator 100 generates a hot heated airflow jet, improving the temperature correction rate of the target object. The controller 127 will then determine whether the thermal equilibrium of the target object has been restored (step S308). If the controller 127 determines that the thermal equilibrium has not been restored (step S308, "No"), the controller will continue to heat the thermal element 113 (step S307) and periodically check to see whether the thermal equilibrium has been restored (step S308). Once the controller 127 determines that thermal equilibrium has been restored to the target object (step S308, "Yes"), the controller will stop heating the thermal element (step 309) and then determine whether the thermal equilibrium of the target object remains intact after deactivation of the thermal element 113 (step S310).

[0056] If it is determined that thermal equilibrium was not maintained following deactivation of the thermal element 113 (step S310, "no"), the controller 127 will reactivate the thermal element 113 by again providing power and waveforms to heat the thermal element 113 (step S307), then periodically determine whether thermal equilibrium of the target object has been restored (step S308), perform a final deactivation of the thermal element (step S309), and make a further determination as to whether the thermal equilibrium of the target object remains intact after deactivation of the thermal element 113 (step S310, "yes"), the controller 127 will then deactivate the actuator 100 and return to periodically checking input data providing information regarding the target object diagnosis (step S302) to determine whether temperature control is again required (step S303).

[0057] Process 300 has several applications to affect improved temperature correction, such as melting frost from LIDAR transmitting surfaces and melting snow obscuring RADAR sensors. In addition, controller 127 may also monitor diagnostics for actuator 100 itself and use process 300 to improve performance of actuator 100, if necessary. For example, deflection of vibratory membrane 120 is required to draw airflow into and out of cavity 111 through orifice 112, and that deflection of vibratory membrane 120 is accomplished via operation of piezoelectric disk 123, which is temperature sensitive. Thus, if the controller 127 determines that the actuator 100 is operating at a sub-optimal level, the controller 127 may determine that operation may be improved by heating the thermal element 113 to increase the temperature of the cavity 111, thereby increasing the temperature of the piezoelectric disc 123 within the proximate vibratory membrane 120 to a temperature that optimizes the performance of the piezoelectric disc 123, and thus the actuator 100 as a whole (e.g., in achieving a target ejection velocity).

[0058] In some cases, heating of the piezoelectric disc 123 via activation of the thermal element 113 may not result in increased performance of the actuator 100, but may nevertheless be performed if the controller 127 determines that operation of the actuator 100 in a heated state can achieve the same results as operation in an unheated state, but with lower power demands (e.g., due to the vibrating membrane 120 moving with substantially the same characteristics but with less energy consumption).

[0059] FIG. 7 shows an assembly 200 in which multiple actuators 100 are integrated into a heat sink 210 for an object requiring temperature control (i.e., a heat load 220). A heat sink is a passive heat exchanger that is designed to be placed in contact with a targeted object requiring thermal cooling, such as an electronic or mechanical device, to provide the targeted object with an increased surface area over which the targeted object can transfer heat to an ambient cooling medium, such as air or a liquid coolant, and the heat is then dissipated away from the targeted object, allowing for regulation of the object's temperature. Heat sinks are commonly used with high power semiconductor devices, such as power transistors, and optoelectronics, such as LIDAR sensors for ADAS, and LEDs for headlamps, where the heat dissipation capabilities of the component itself are insufficient to moderate its temperature.

[0060] The assembly in Fig. 7 presents an example and shows an actuator 100 according to the present invention integrated into a heat sink 210 to improve the effectiveness of the heat sink in dissipating heat from a thermal load 220 in contact with the heat sink. In this example, the heat sink 210 comprises two vanes 211 and the actuator 100 is integrated only into the first vane 211a, but it should be understood that in other embodiments the actuator may be integrated into the second vane 211b as well as any additional vanes 211 provided on the heat sink 210. The vane 211a comprises three cavities 111 formed therethrough and serves as a cavity layer 110 for each actuator 100. Three separate pairs of vibrating membranes 120a / 120b are aligned with the respective cavities 111 and positioned on opposite sides of the vane 211a. FIG. 7 shows a single power supply 126 and controller 127, it being understood that the illustrated power supply 126 and controller 127 may be in communication with and control each of the actuators 100, or a separate power supply and / or controller may be provided for each individual actuator 100.

[0061] With actuators 100 formed on vanes 211a, the boundary surface 111' of each cavity 111 will therefore provide an increased surface area contact between the heat sink 210 and the ambient air. This increased surface area increases the passive dissipation capability of the heat sink 210, which is enhanced even more significantly by the operation of each actuator 100. As the actuators 100 draw airflow from the ambient environment into their respective cavities 111, the air is then brought into contact with the corresponding boundary surface 111' for dissipation of heat from the vanes 211a to the atmosphere, and the exhaust of that air from the cavities 111 as the airflow jets then removes the heat transferred from the heat sink 210. In this manner, the operation of the integrated actuator 100, with its suction and blowing action of the cyclical airflow, promotes a higher air exchange rate with the vanes 211a, which in return results in a higher heat transfer rate for removing heat from the heat sink 210, i.e., from the thermal load 220.

[0062] FIG. 8 illustrates a process 400 that may be used to operate the actuator 100 of FIG. 7 with a thermal load 220, which represents a target object for cooling. In this example, the actuator 100 is configured to affect temperature control of the thermal load 220 through heat dissipation via the heat sink 210, and the controller 127 is configured to receive input data providing information regarding the need for temperature control of the thermal load 220, for example, from a management system associated with the thermal load 220. In response to activation of the cooling system (step S401), the controller 127 will periodically check the input data providing information regarding the temperature of the thermal load 220 (step S402) to determine whether cooling is required (step S403). If it is determined that cooling is not required (step S403, "No"), the process will forgo activation of the actuator 100 and continue to periodically check the input data providing information regarding the temperature of the thermal load 220 (step S402) to determine whether cooling is required (step S403).

[0063] If it is determined that cooling is required (step S403, "Yes"), the controller 127 determines specific operating parameters for controlling each actuator 100 based on the location of each actuator 100 provided by the management system and the IP address associated with the thermal load at the location of each synthetic jet actuator (step S404). The controller 127 then determines whether thermal balance of the thermal load 220 has been restored (step S406). If the controller 127 determines that thermal balance has not been restored, the controller 127 continues to keep the actuators 100 activated (step S405) and periodically determine whether thermal balance of the thermal load 220 has been restored (step S406). Once it is determined that thermal balance of the thermal load 220 has been restored (step S406, "YES"), the controller 127 deactivates the actuator 100 (step S407) and returns to periodically checking the input data providing information regarding the temperature of the thermal load 220 (step S402) to determine whether cooling is again required (step S403).

[0064] In process 400, the controller 127 may separately control the power, frequency, and waveform of each actuator 100 such that the dissipation of heat is adaptively controlled through the heat sink 210 based on the thermal load 220, which may be any suitable device such as, but not limited to, an LED, LIDAR, or other object requiring heat dissipation.

[0065] Although the present invention has been described with reference to detailed embodiments, it will be understood by those skilled in the art that the foregoing disclosure deals only with exemplary embodiments, and that the scope of the present invention is not limited to the disclosed embodiments, but may include additional embodiments encompassing various changes and modifications relative to the examples disclosed herein without departing from the scope of the present invention as defined in the accompanying claims, etc.

[0066] Although some of the foregoing examples forgo illustration and / or discussion of some elements discussed in other examples, it should be understood that each example may include or be included with each element from one or more of the examples. For example, although some examples forgo illustration and / or explicit discussion of a tacky adhesive layer and / or an outer layer (such as tacky adhesive 122 and outer layer of FIG. 3), it should be understood that each example discussed within may include these elements. Additionally, while the foregoing examples are discussed in connection with airflow, it should be understood that jet actuators according to the present invention are not limited to generating air and airflow, but may be used with any suitable fluid for generating a corresponding fluid flow.

[0067] To the extent necessary to understand and complete the disclosure of the present invention, all publications, patents, and patent applications mentioned herein are expressly incorporated herein by reference to the same extent as if each was individually incorporated as such. No license, express or implied, is granted to any patent incorporated herein.

[0068] The present invention is not limited to the exemplary embodiments illustrated herein, but is instead characterized by the accompanying claims, which do not in any way limit the scope of the present disclosure.

Claims

1. A synthetic jet actuator, comprising: a cavity layer, the cavity layer comprising an internal cavity for receiving a quantity of fluid and an orifice providing fluid communication between the internal cavity and an outside atmosphere; a vibratory membrane comprising a piezoelectric material adapted to deflect the vibratory membrane in response to an electrical signal; a controller configured to control delivery of an electrical signal to the piezoelectric material to control movement of the vibrating membrane; Equipped with the internal cavity has an opening in a planar surface of the cavity layer, the vibratory membrane being positioned adjacent to the planar surface having the opening, the vibratory membrane adapted as an encapsulating surface for the opening; the vibratory membrane is adapted to compress and expand a volume within the internal cavity based on a deflection generated by the piezoelectric material to generate a fluid flow between the internal cavity and the outside air through the orifice; the controller is further configured to receive input data indicative of a need for temperature control of a targeted object, and to control delivery of the electrical signal to the piezoelectric material to control movement of the vibrating membrane under at least one predetermined parameter to affect temperature control of the targeted object; the synthetic jet actuator further comprising a thermal element disposed in the internal cavity of the cavity layer; The controller is further configured to control a temperature of the thermal element to modify a temperature of the internal cavity, thereby enabling temperature control of a fluid flow exhausted from the internal cavity to the outside atmosphere.

2. 10. The synthetic jet actuator of claim 1, wherein the controller is configured to receive the input data and use the input data to determine at least one parameter for affecting temperature control to achieve a target temperature or target temperature range of the targeted object.

3. 10. The synthetic jet actuator of claim 1, wherein the controller is configured to receive the input data and use the input data to determine at least one parameter for affecting temperature control of the targeted object.

4. 10. The synthetic jet actuator of claim 1, wherein the controller is configured to control the movement of the vibrating membrane under at least one predetermined parameter selected from frequency, amplitude, waveform, phase, duty cycle, and modulation frequency.

5. The synthetic jet actuator of claim 4 , wherein the controller is configured to control movement of the vibrating membrane to thereby modify the at least one predetermined parameter as required.

6. The synthetic jet actuator of claim 1 , wherein the synthetic jet actuator is located within a vehicle.

7. 7. The synthetic jet actuator of claim 6, wherein the controller is configured to receive input data from at least one on-board vehicle source selected from a vehicle electronic control unit (ECU), a vehicle cooling system data management platform (DMP), and a DMP of the targeted object.

8. 7. The synthetic jet actuator of claim 6, wherein the controller is configured to receive input data from at least one source selected from vehicle-to-vehicle (V2V) communication in another vehicle or moving platform, one or more transmitters in a network of autonomous vehicles, or a control center coordinating multiple moving platforms.

9. the controller is further configured, upon receiving the input data, to activate and control delivery of the electrical signal to the piezoelectric material to operate the vibrating membrane and thereby affect temperature control of the targeted object; the controller is further configured to determine whether there is a need to affect a modified temperature control of the targeted object to achieve a greater heat transfer than would be possible from operation of the vibrating membrane alone; The controller: if a determination is made that modified temperature control is required, activating and controlling the temperature of the thermal element while continuing to control the motion of the vibrating membrane to affect modified thermal management of the targeted object; if a determination is made that modified temperature control is not required, continuing operation of the vibrating membrane to affect temperature control of the targeted object without operation of the thermal element. The synthetic jet actuator of claim 1 , further configured to:

10. the controller is further configured to determine whether the targeted object has reached thermal equilibrium to achieve a target temperature or a target performance level subsequent to activating the thermal element to affect a modified temperature control; The controller: if a determination is made that the targeted object has reached thermal equilibrium, deactivating the thermal element and ceasing modified temperature control of the targeted object; if a determination is made that the targeted object has not reached thermal equilibrium, maintaining operation of the thermal element for continued corrective temperature control of the targeted object. The synthetic jet actuator of claim 9 , further configured to:

11. the controller is further configured to determine whether thermal equilibrium of the targeted object is maintained following deactivating the thermal element to cease modified temperature control of the targeted object; The controller: if a determination is made that thermal equilibrium is not being maintained, reactivating and controlling the temperature of the thermal element while continuing to control the movement of the vibrating membrane and updating a revised temperature control of the targeted object; if a determination is made that thermal equilibrium is maintained, then ceasing operation of the vibrating membrane and ceasing temperature control of the targeted object. The synthetic jet actuator of claim 10 , further configured to:

12. 2. The synthetic jet actuator of claim 1, wherein the thermal element comprises a heating coil, and the controller is configured to control a temperature of the thermal element by controlling power supplied to the heating coil.

13. 1. A thermally dissipative structure for dissipating heat from a thermal load, comprising: The thermal spreading structure comprises a synthetic jet actuator as described in claim 1 , wherein the thermal spreading structure is integrated into a surface of the thermal spreading structure.

14. The heat spreading structure of claim 13 , wherein the heat spreading structure is a heat sink and the synthetic jet actuator is integrated into a vane of the heat sink.

15. the vane of the heat sink is configured as the cavity layer of the synthetic jet actuator, the internal cavity being formed within the vane, the opening being formed in a planar surface of the vane, and the orifice being formed in an exterior surface of the vane to provide fluid communication between the internal cavity and an external atmosphere; 15. The heat spreading structure of claim 14, wherein the vibrating membrane is positioned adjacent to the planar surface of the vane having the opening, the vibrating membrane adapted as an encapsulating surface for the opening.

16. The heat spreading structure of claim 14 , wherein a plurality of synthetic jet actuators are integrated into a common vane of the heat sink.

17. The thermally diffusive structure of claim 16, wherein the multiple synthetic jet actuators are powered by a common power source and controlled by a common controller.

18. The thermal spreading structure of claim 17 , wherein the controller is configured to enable control of individual synthetic jet actuators under custom operating parameters based on a position of the synthetic jet actuator on the heat sink and a thermal load at the location of the synthetic jet actuator.

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