Passive fluid flow control devices and systems

Abstract

A cooling system is disclosed. The cooling system may include a flow path including a main path and a secondary path. The secondary path may have an inlet and an outlet. The inlet may be in fluid communication with a first portion of the main path and the outlet may be in fluid communication with a second portion of the main path. The cooling system may include a passive fluid flow controller. The passive fluid flow controller may be disposed in the main path between the first portion and the second portion. The passive fluid flow controller may regulate an amount of coolant routed from the main path through the secondary path inlet to the secondary path. The passive fluid flow controller may prevent particles from entering the secondary path via the secondary path inlet.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 313,467, filed February 24, 2022, entitled "PASSIVE FLUID FLOW CONTROLLING DEVICE AND SYSTEM," the disclosure of which is incorporated herein by reference in its entirety for all purposes.

[0002] FIELD OF THE DISCLOSURE This disclosure relates generally to flow control systems, and more specifically to passive fluid flow control devices and systems. [Background technology]

[0003] Electronic devices can generate heat during operation. For example, in vehicles, such as electric vehicles, there are electronic components and devices that generate heat. A cooling system is desired to dissipate the heat and keep the electronic components operating within their target operating temperature ranges. Summary of the Invention

[0004] In one aspect, a cooling system is disclosed. The cooling system can include a flow path including a main path for cooling a first heat source and a secondary path for cooling a second heat source. The secondary path has an inlet and an outlet. The inlet is in fluid communication with a first portion of the main path and the outlet is in fluid communication with a second portion of the main path. The cooling system can include a passive fluid flow controller disposed in the main path between the first portion and the second portion. The passive fluid flow controller is configured to regulate an amount of coolant in the flow path that is routed from the main path through the inlet of the secondary path to the secondary path.

[0005] In one embodiment, the passive fluid flow controller includes a plug and a spring.

[0006] In one embodiment, the passive fluid flow controller includes an elastic band and a flexible tube.

[0007] In one embodiment, the passive fluid flow controller includes one or more flaps coupled to an inner wall of the main passage.

[0008] In one embodiment, the passive fluid flow controller includes structures that expand and / or compress in response to temperature changes to adjust the opening of the primary pathway.

[0009] In one embodiment, the electric vehicle includes a cooling system. A first heat source can be cooled by a primary path and a second heat source can be cooled by a secondary path. The first heat source can be a hotter heat generating device and the second heat source can be a cooler heat generating device. The first heat source can include a battery and the second heat source can include a vehicle electronics system.

[0010] In one aspect, a system is disclosed. The system can include a flow path including a main pathway and a secondary pathway. The secondary pathway has an inlet and an outlet. The inlet is in fluid communication with a first portion of the main pathway and the outlet is in fluid communication with a second portion of the main pathway. The system can include a heat source coupled to the secondary pathway. The heat source has a channel that defines at least a portion of the secondary pathway. The system can include a fluid flow controller configured to prevent particles from entering the secondary pathway via the inlet of the secondary pathway. A dimension of the particle is greater than a dimension of the channel of the heat source.

[0011] In one embodiment, the fluid flow controller includes a filter configured to filter particles.

[0012] In one embodiment, the fluid flow controller is disposed in the main channel upstream of the inlet of the secondary channel. The fluid flow controller can be configured to increase the velocity of the particles. The fluid flow controller can be configured to filter the particles.

[0013] In one embodiment, the fluid flow controller is configured to cause particles to flow in the main channel past an inlet to the secondary channel.

[0014] In one embodiment, the heat source includes an electronic system that includes a cooling solution, the cooling solution including the channel.

[0015] In one embodiment, an electric vehicle includes a system, a vehicle electronics system cooled by a secondary path and including a channel and a heat source, and a battery cooled by a primary path.

[0016] In one embodiment, the system can further include a passive fluid flow controller disposed in the main pathway between the first portion and the second portion, The passive fluid flow controller can be configured to regulate an amount of coolant routed from the main pathway through an inlet of the secondary pathway to the secondary pathway.

[0017] In one aspect, a cooling system is disclosed. The cooling system can include a flow path including a main path for cooling a first heat source and a secondary path for cooling a second heat source. The secondary path has an inlet and an outlet. The inlet is in fluid communication with a first portion of the main path and the outlet is in fluid communication with a second portion of the main path. The cooling system can include a passive fluid flow controller configured to prevent particles in the coolant from entering the secondary path via the inlet of the secondary path such that particles in the coolant flow within the main path past the outlet of the secondary path. A dimension of the particles is greater than a threshold dimension.

[0018] In one embodiment, the passive fluid flow controller includes a filter disposed on the inlet of the secondary path.

[0019] In one embodiment, the passive fluid flow controller includes a structure in the main channel upstream of an inlet to the secondary channel, the structure being configured to increase the velocity of the particles.

[0020] In one embodiment, the electric vehicle includes a cooling system. A first heat source can be cooled by a primary path and a second heat source can be cooled by a secondary path. The first heat source can be a hotter heat generating device and the second heat source can be a cooler heat generating device. The first heat source can include a battery and the second heat source can include a vehicle electronics system. [Brief description of the drawings]

[0021] Specific implementations will now be described with reference to the following drawings, which are provided by way of example and not limitation.

[0022] [Figure 1] FIG. 2 illustrates a cooling loop in an exemplary cooling system configured to dissipate heat from high heat and low heat devices.

[0023] [Figure 2A] 4 is a graph showing the relationship between the fin spacing of a cold plate of an electronic control unit (ECU) and the temperature of the ECU.

[0024] [Figure 2B] 1 is a graph showing cold plate flow rate versus cold plate pressure drop for different fin spacings.

[0025] [Diagram 3] 1 is a schematic diagram of a fluid flow controller in a cooling system according to one embodiment.

[0026] [Figure 4] 2 is a schematic diagram of a fluid flow controller in a cooling system according to another embodiment.

[0027] [Figure 5A] 1 is a schematic diagram of a fluid flow controller in a cooling system in a first state in which there is less fluid flow in the cooling system according to another embodiment.

[0028] [Figure 5B] FIG. 5B is a schematic diagram of a fluid flow controller in the cooling system of FIG. 5A in a second state where there is more fluid flow in the cooling system.

[0029] [Figure 5C] 5C is a schematic cross-sectional side view of the fluid flow controller of FIGS. 5A and 5B in a first condition. FIG.

[0030] [Figure 6A] 2 is a schematic perspective view of a fluid flow controller in a first state according to another embodiment. FIG.

[0031] [Figure 6B] 6B is a schematic perspective view of the fluid flow controller of FIG. 6A in a second state.

[0032] [Figure 7] 2 is a schematic diagram of a fluid flow controller in a cooling system according to another embodiment.

[0033] [Figure 8] 2 is a schematic diagram of a fluid flow controller in a cooling system according to another embodiment.

[0034] [Figure 9A] 2 is a schematic cross-sectional view of a fluid flow controller in a cooling system according to another embodiment.

[0035] [Figure 9B] FIG. 9B is a schematic perspective view of the fluid flow controller of FIG. 9A.

[0036] [Figure 9C] FIG. 2 is a schematic perspective view of a centrifuge.

[0037] [Figure 10A] 2 is a schematic cross-sectional view of a fluid flow controller in a cooling system according to another embodiment.

[0038] [Figure 10B] FIG. 10B is a schematic perspective view of the fluid flow controller of FIG. 10A.

[0039] [Figure 10C] FIG. 1C is a schematic perspective view of one half of the fluid flow controller of FIGS. 10A and 10B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] The following detailed description presents various descriptions of specific embodiments. However, the innovations described herein can be implemented in many different ways, for example, as defined and encompassed by the claims. In this description, reference is made to the drawings, in which like reference numbers and / or terms may indicate identical or functionally similar elements. It will be understood that the elements illustrated in the drawings are not necessarily drawn to scale. It will further be understood that a particular embodiment may include more elements than shown in the drawings and / or a subset of the elements illustrated in the drawings. Furthermore, some embodiments may incorporate any suitable combination of features from two or more drawings.

[0041] In a vehicle, such as an electric vehicle, there may be one or more cooling systems. For example, a vehicle may include a battery coolant loop, a heating, ventilation, and air conditioning (HVAC) cabin and battery refrigerant loop, an inverter, charger, and motor / transmission cooling loop, and a motor oil cooling loop. There may be electronic components or electronic equipment with different cooling needs in the same loop. For example, in a battery cooling loop, there may be a high heat generating device (e.g., a battery) and a low heat generating device (e.g., an electronic control unit such as a vehicle electronic control unit, another vehicle electronic system, etc.) that generates less heat than the high heat generating device. Because the low heat generating device generates less heat, the low heat generating device can be cooled with less coolant flow than the high heat generating device.

[0042] FIG. 1 illustrates a cooling loop in an exemplary cooling system 1 configured to dissipate heat from a high heat device (e.g., a battery 10) and a low heat device (e.g., a vehicle electronic control unit (ECU) 12). The vehicle ECU 12 may include an autopilot ECU, a driver assistance ECU, an infotainment ECU, and the like. In the present disclosure, the battery 10 and the vehicle ECU 12 may be used as examples of the high heat device and the low heat device, respectively, but any other suitable components or equipment that generate heat may be the high heat device and the low heat device regardless of their power dissipation, so long as the high heat device and the low heat device have different cooling needs. The cooling system 1 includes a restrictor 14 that restricts or controls the flow of coolant flowing through the cooling loop. The cooling loop includes a primary loop 16 for cooling the battery 10 and a secondary loop 18 for cooling the vehicle ECU 12. The coolant flowing through the primary loop 16 can reduce the heat of the battery 10, and the coolant flowing through the secondary loop 18 can reduce the heat of the vehicle ECU 12. The cooling system 1 may include a pump 20 that drives the flow of coolant within the cooling system 1. The cooling system 1 may also include any combination of chillers, radiators, or cooling systems (not shown in FIG. 1 ) that may reduce the temperature of the coolant. The arrows in the flow paths (main path or loop 16 and secondary path or loop 18) indicate example coolant flow directions. Although embodiments of the present disclosure may refer to the main loop 16 and secondary loops, any suitable principles and advantages disclosed herein may be applied to any suitable main path and any suitable secondary path.

[0043] During use, the battery 10 may generate a significant amount of heat. To ensure proper operation of the battery 10 and / or other sensitive components near the battery 10 that may be affected by the heat from the battery 10, the battery 10 may be cooled to an operable temperature within the operating temperature range.

[0044] The vehicle ECU 12 may include, for example, any custom electronics, a graphics processing unit (GPU), a microcontroller unit (MCU), a heat spreader, and a cold plate (e.g., a heat sink). The cold plate may include cooling fins, which are spaced apart by a spacing between them. The vehicle ECU 12 may be cooled to an operable temperature within an operating temperature range for proper operation of the vehicle ECU 12 and / or other sensitive components near the vehicle ECU 12 that may be affected by heat from the vehicle ECU 12. Coolant may pass through channels between the cooling fins of the cold plate to cool the vehicle ECU 12.

[0045] The battery 10 typically generates more heat than the vehicle ECU 12. Thus, compared to the battery 10, the vehicle ECU 12 can operate within its operating temperature with less cooling than the battery 10. For example, the flow rate of coolant to maintain the operable temperature of the battery 10 may be about 5 times (e.g., 3 to 7 times, or 4 to 6 times) the flow rate of coolant to maintain the operable temperature of the vehicle ECU 12. If the vehicle ECU 12 is placed in the primary loop 16 and the vehicle ECU 12 is overcooled, the pressure in the primary loop 16 may drop significantly, which may adversely affect the cooling function of the cooling system 1. In other words, the impedance of a cooling loop including the serially connected paths for cooling the vehicle ECU 12 and the battery 10 may be significantly higher than the impedance of a cooling loop that connects the primary loop 16 and the secondary loop 18 in parallel. The serially connected paths may cause relatively high pump power consumption, noise and / or system pressure, which may adversely affect the reliability of the cooling system. As shown in FIG. 1, the vehicle ECU 12 may be placed in a secondary loop 18, and a portion of the coolant flowing through the primary loop 16 may be routed to the secondary loop 18 to cool the vehicle ECU 12. By arranging the secondary loop 18 for the vehicle ECU 12 in this manner, the pressure drop in the primary loop 16 may be reduced or minimized. There may be other considerations for diverting a portion of the flow in the primary loop 16 to the secondary loop 18. Regardless of the reason for diverting the flow partially, the proposed solutions disclosed herein may be applicable. The principles and advantages disclosed herein may be implemented in any suitable device or system for diverting a flow path to multiple flow paths. For example, although a loop for circulating a coolant in the system may be used as an example herein, the principles and advantages disclosed herein may be implemented in a system that does not circulate a coolant in the system.

[0046] The restrictor 14 may be used to route a portion of the coolant flowing through the primary loop 16 to the secondary loop 18. The restrictor 14 may be an active valve in certain applications. However, using such an active component or device may be complicated and / or expensive. Thus, in certain applications, a simpler, less expensive restriction component or device may be advantageous.

[0047] Various embodiments disclosed herein relate to passive flow control devices that can be used as restrictors in cooling systems, such as restrictor 14 in cooling system 1. The passive flow control devices disclosed herein can be configured to function without routine maintenance or service. The passive flow control devices disclosed herein can enable the integration of relatively high performance cooling solutions for vehicle electronics that may have large surface area cooling fins (smaller gaps between fins). This can improve system performance. The self-regulating flow control embodiments disclosed herein enable more energy efficient operation of the battery cooling loop in electric vehicles. At the same time, noise, vibration and harshness (NVH) of electric vehicles can be reduced. These improvements can benefit one or more of reliability, driving range or quality of customer experience.

[0048] 2A is a graph showing the relationship between fin spacing of a cold plate of an ECU (e.g., vehicle ECU 12) and the temperature of the vehicle ECU 12. The graph in FIG. 2A shows that closer spacing can provide better cooling than larger spacing.

[0049] FIG. 2B is a graph showing the relationship between cold plate flow rate and cold plate pressure drop. The graph in FIG. 2B shows that the higher the flow rate in the secondary loop 18, the higher the pressure drop. The graph in FIG. 2B also shows that the smaller the fin spacing, the higher the pressure drop. Thus, as more coolant is sent to the secondary loop 18, the overall pressure drop of the cooling system 1 may be higher. In some applications, reducing or minimizing the pressure drop in the cooling system 1 while still providing sufficient cooling to the vehicle ECU 12 may be important to avoid or mitigate excessive power consumption of the pump driving the coolant flow in the cooling system 1. The ability to tune the cold plate fin spacing(s) to the design specifications of any particular ECU is important to optimize the cooling system 1 for improved performance.

[0050] The vehicle ECU 12 may be sensitive to relatively small particles in the coolant due to the relatively small fin spacing of the cold plate of the vehicle ECU 12. For example, if the particle size is larger than the spacing size, the particle may disrupt the flow of the coolant by clogging the fin spacing. On the other hand, the battery 10 may be less sensitive to particles in the coolant. Various embodiments disclosed herein relate to flow control devices that can prevent or impede particles of certain sizes from entering the secondary loop 18. In some embodiments, the flow control device can filter particles and prevent or impede the particles from entering the secondary loop 18.

[0051] FIG. 3 is a schematic diagram of a fluid flow controller 30 in a cooling system 2, according to one embodiment. The cooling system 2 of FIG. 3 may have a similar overall structure as the cooling system 1 of FIG. 1. The fluid flow controller 30 is an example of the restrictor 14 shown in FIG. 1. The cooling system 2 may include a flow path having a main loop 16 and a secondary loop 18. The fluid flow controller 30 may be disposed in the main loop 16 of the flow path. The fluid controller 30 may be disposed in the main loop 16 of the cooling system 2 between an inlet 18a and an outlet 18b of the secondary loop 18. The inlet 18a is in fluid communication with a first portion of the main loop 16, and the outlet 18b is in fluid communication with a second portion of the main loop 16. The main loop 16 may be for cooling a higher temperature heat generating device or a first heat source, and the secondary loop 18 may be for cooling a lower temperature heat generating device or a second heat source that generates less heat than the first heat source. The cooling system 2 can dissipate heat generated from multiple heat generating sources (e.g., electronic devices) coupled to a flow path (e.g., connected in a manner that allows thermal communication). The heat generating sources can be referred to as heat sources. The electronic devices can include high heat generating devices (see FIG. 1) that can generate more heat than low heat generating devices (e.g., vehicle ECU 12), such that more cooling is desired for the high heat generating devices than for the low heat generating devices. The high heat generating devices can be referred to as higher temperature heat generating devices. The low heat generating devices can be referred to as lower temperature heat generating devices.

[0052] The flow path can be configured to allow more coolant to flow in the primary loop 16 than in the secondary loop 18. In some embodiments, the fluid flow controller 30 can control the flow in the secondary loop 18 based at least in part on the heat generated by the heat source. For example, the fluid flow controller 30 can direct 10%-20%, 10%-15%, or 15%-20% of the fluid flow in the primary loop 16 to the secondary loop 18.

[0053] The fluid flow controller 30 may be a passive flow restrictor or a passive flow controller. The fluid flow controller 30 is a passive device that can dynamically adjust the fluid flow in the flow path. The fluid flow controller 30 may include a plug 32 coupled to a portion of the cooling system 2 by a spring 34. The plug 32 and the spring 34 may provide resistance to the flow of coolant in the primary loop 16. The flow of coolant in the primary loop 16 may displace the plug 32 in the direction of the coolant flow. The amount of displacement of the plug 32 may vary based at least in part on the flow rate of the coolant in the primary loop 16 and / or the spring force or tensile strength of the spring 34. The resistance to flow may cause at least a portion of the coolant in the primary loop 16 to flow into the secondary loop 18. The spring force or tensile strength of the spring 34 may be selected to deliver a desired amount and / or ratio of coolant to flow through the secondary loop 18 to the vehicle ECU 12. As the amount and / or rate of coolant flow in the primary loop 16 increases, the fluid force can overcome the spring force, pushing the plug 32 to the right in FIG. 3, causing a greater displacement and therefore a less restrictive fluid path between the plug 32 through which the coolant flows and the inner wall of the primary loop 16. Such a self-regulating or passive feature can be beneficial in certain system design configurations. A combination of plug shape and spring strength can be used to regulate the flow in the secondary loop 18 at different flow values ​​in the primary loop 16.

[0054] In the illustrated embodiment, the plug 32 has a generally triangular or conical shape, however, the plug 32 may have any other suitable shape. For example, a more flow-resistant shape may be used to increase the amount of coolant delivered to the vehicle ECU 12. In some embodiments, the surface of the plug 32 may be smoothed to increase the amount of coolant delivered to the main loop 16.

[0055] A plug 32 having particular characteristics and / or a spring 34 having a particular spring force can be selected to control the amount of coolant that is directed to the secondary loop 18. For example, the plug 32 and spring 34 can be configured to direct 10%-20% of the coolant flowing through the primary loop 16 to the secondary loop 18.

[0056] Figure 4 is a schematic diagram of a fluid flow controller 40 in a cooling system 3, according to one embodiment. The cooling system 3 of Figure 4 may have a similar overall structure to the cooling system 1 of Figure 1. The fluid flow controller 40 is an example of the restrictor 14 shown in Figure 1. The fluid flow controller 40 may be located in the primary loop 16 of the cooling system 3, between the inlet 18a and outlet 18b of the secondary loop 18.

[0057] The fluid flow controller 40 may be a passive flow restrictor or a passive flow rate controller. The fluid flow controller 40 is a passive device that can dynamically adjust the fluid flow in the flow path. The fluid flow controller 40 may include an elastic band 42, such as a rubber band, wrapped around an elastic, expandable or flexible tube 44, such as a rubber tube, that at least partially defines a portion of the main loop 16. The elastic band 42 may provide resistance to the flow of coolant in the main loop 16. The flow of coolant in the main loop 16 may push against the inner wall of the flexible tube 44, thereby deforming the flexible tube 44 and increasing the diameter of the flow path defined by the flexible tube 44. The amount of deformation of the flexible tube 44 may vary based at least in part on the flow rate of coolant in the main loop 16 and / or the elasticity of the elastic band. The resistance to flow may allow at least a portion of the coolant in the main loop 16 to flow into the secondary loop 18. The elasticity of the elastic band 42 may be selected to deliver a desired amount and / or ratio of coolant to flow through the secondary loop 18 to the vehicle ECU 12 .

[0058] The dimensions and material properties of the elastic band 42 and / or the flexible tubing 44 can be selected to control the amount of coolant delivered to the secondary loop 18. For example, the flow controller 40 can deliver to the secondary loop 18 between 10% and 20% of the amount of coolant flowing through the primary loop 16.

[0059] FIG. 5A is a schematic diagram of a fluid flow controller 50 in a cooling system 3 in a first state where there is no fluid flow or there is less fluid flow in the cooling system 4, according to one embodiment. FIG. 5B is a schematic diagram of a fluid flow controller 50 in a cooling system 4 in a second state where there is more fluid flow in the cooling system 4. FIG. 5C is a schematic cross-sectional side view of the fluid flow controller 50 in the first state. The cooling system 4 of FIGS. 5A and 5B may have a similar overall structure to the cooling system 1 of FIG. 1. The fluid flow controller 50 is an example of the restrictor 14 shown in FIG. 1. The fluid flow controller 50 may be located in the primary loop 16 of the cooling system 4 between the inlet 18a and the outlet 18b of the secondary loop 18.

[0060] The fluid flow controller 50 may be a passive flow restrictor or a passive flow controller. The fluid flow controller 50 is a passive device that can dynamically adjust the fluid flow in a flow path. The fluid flow controller 50 may include a flap 52, such as a rubber flap, coupled to an inner wall 54 of a portion of the primary loop 16. The flap 52 may provide resistance to the flow of coolant in the primary loop 16. The flow of coolant in the primary loop 16 pushes against the flap 52, displacing the flap 52 and allowing the coolant to pass through the fluid flow controller 50. The amount of displacement of the flap 52 may vary based at least in part on the flow rate of the coolant in the primary loop 16. The resistance to flow may allow at least a portion of the coolant in the primary loop 16 to flow into the secondary loop 18. The material and / or shape of the flap 52 may be selected to deliver a desired amount and / or ratio of coolant to flow through the secondary loop 18 to the vehicle ECU 12.

[0061] The material and / or shape of the flap 52 can be selected to control the amount of coolant sent to the secondary loop 18. For example, the flow controller 50 can send 10%-20% of the coolant flowing through the primary loop 16 to the secondary loop 18.

[0062] FIG 6A is a schematic perspective view of a fluid flow controller 60 in a first state (first temperature) according to one embodiment. FIG 6B is a schematic perspective view of the fluid flow controller 60 in a second state (second temperature). The fluid flow controller 60 is an example of the restrictor 14 shown in FIG 1. The fluid flow controller 60 may be implemented in a cooling system in a manner similar to the fluid flow controller 50 shown in FIGS 5A-5C. The fluid flow controller 60 may be disposed in the primary loop 16 of the cooling system between the inlet and outlet of the secondary loop 18, similar to the exemplary fluid flow controller of FIGS 3-5C.

[0063] The fluid flow controller 60 may be a passive flow restrictor or a passive flow rate controller. The fluid flow controller 60 is a passive device that can dynamically adjust the fluid flow in the flow path. The fluid flow controller 60 utilizes the temperature-dependent behavior of a shape memory alloy to adjust the opening of the restrictor to change the fluid flow. The fluid flow controller 60 may include a base plate 62, a shape memory spring 64, and a movable plate 66 that is connected to the base plate 62 by the shape memory spring 64 and is movable during operation of the cooling system 60. The shape memory spring 64 may expand and compress in response to temperature changes. When the coolant flows through the flow path 68, the temperature of the coolant may change the temperature of the shape memory spring 64. In a first state (see FIG. 6A), the shape memory spring 64 expands and the movable plate 66 is located at a first position. In a second state (see FIG. 6B), the shape memory spring 64 compresses and the movable plate 66 is located at a second position. The shape memory spring 64 can expand and compress as the temperature of the coolant changes (which changes the temperature of the shape memory spring 64). Thus, intermediate states can exist between a first state having a first temperature and a second state having a second temperature.

[0064] In the first state, the diameter of the flow passage 68 is at a minimum, and in the second state, the diameter of the flow passage 68 is at a maximum. Thus, if the fluid flow controller is positioned similarly to the fluid flow controllers of Figures 3 through 5C, more coolant will flow through the main loop 16 in the first state, and less coolant will flow through the main loop 16 in the second state.

[0065] Each of the shape memory springs 64 in the fluid flow controller 60 may be the same or different from one another. For example, springs having different properties (e.g., different expansion / compression rates) may be used to further control the flow rate of coolant in the cooling system. The properties of the shape memory springs 64 and / or the shape and dimensions of the movable plate 66 may be selected to control the amount and / or ratio of coolant delivered to the secondary loop 18. For example, the fluid flow controller 60 may deliver 10%-20% of the amount of coolant flowing through the primary loop 16 to the secondary loop 18.

[0066] The fluid flow controllers 30, 40, 50, 60 shown in Figures 3-6B utilize the mechanical properties of components (e.g., the plug 32 and spring 34 of the fluid flow controller 30, the elastic band 42 and flexible tube 44 of the fluid flow controller 40, and the flap 52 of the fluid flow controller 50, and the shape memory spring 64 of the fluid flow controller 60) to control the flow of coolant in the primary loop 16 and the secondary loop 18. Thus, the fluid flow controllers 30, 40, 50, 60 are passive controllers. As discussed above, compared to active flow restrictors, the passive fluid flow controllers disclosed herein can enable cooling systems that are simpler, more cost-effective, and / or consume less energy.

[0067] The fluid flow controller disclosed herein can control the flow of coolant driven to different portions of a flow path (e.g., a primary loop and a secondary loop) in a cooling system. Figures 3 to 6B relate to a fluid flow controller that can control the amount of coolant driven to different portions of a flow path. Figures 7 to 10C relate to a fluid flow controller that can control the flow of specific particles in the coolant in the primary loop 16 and the secondary loop 18. Any suitable principles and advantages of these embodiments related to controlling the flow of coolant and / or controlling the flow of particles can be implemented together with each other. The technical solutions of Figures 7 to 10C can prevent or impede particles larger than the channels in the cooling solution of a heat generating source (e.g., a vehicle ECU) cooled by the secondary loop of the cooling system from entering the secondary loop 18.

[0068] FIG. 7 is a schematic diagram of a fluid flow controller 70 in a cooling system 5, according to one embodiment. The cooling system 5 of FIG. 7 may have a similar overall structure to the cooling system 1 of FIG. 1. The cooling system 5 may include a flow path having a primary loop 16 and a secondary loop 18. The fluid flow controller 70 may include a filter 72. In some embodiments, the filter 72 may be disposed at the inlet 18a of the secondary loop 18. The cooling system 5 may dissipate heat generated from multiple heat generating sources (e.g., one or more electronic devices, one or more batteries, etc.) coupled to the flow path (e.g., connected in a manner that allows thermal communication). The heat generating sources may include high heat generating devices (see battery 10 of FIG. 1) that may generate more heat than low heat generating devices (e.g., vehicle ECU 12), such that more cooling is desired for the high heat generating devices than the low heat generating devices. In some implementations, for example, as described above, the vehicle ECU 12 may be sensitive to relatively small particles in the coolant. For example, the vehicle ECU 12 may be more sensitive to smaller particles than high heat generating devices (e.g., batteries). In some embodiments, the filter 72 of the fluid flow controller 70 may filter particles in the coolant at the inlet 18a of the secondary loop 18. This may prevent or reduce the number of particles in the coolant larger than a threshold size from entering the secondary loop 18. The fluid flow controller 70 may include a flow rate controller 74. In some embodiments, the flow rate controller 74 may be implemented in accordance with any suitable principles and advantages of one or more of the fluid flow controllers 30, 40, 50, 60.

[0069] The filter 72 can filter particles larger than a threshold size to prevent or reduce the number of such particles from entering the secondary loop 18. Such filtering can reduce or eliminate the impact of a relatively small filter on the cooling solution of a low heat generating device. For example, filtering can reduce or eliminate clogging of relatively small channels between fins in a cold plate of an electronic system such as the vehicle ECU 12. In the primary loop 16, the coolant can flow at a flow rate that is greater than the flow rate of the coolant in the secondary loop 18. If particles larger than a threshold size are contained in the coolant flowing toward the secondary loop 18, the particles can be filtered by the filter 72. Thus, the filter 73 can prevent the particles from entering the secondary loop 18. The filtered particles can be swept away from the filter 72 by the flow of coolant in the primary loop 16 and travel within the primary loop 16. Thus, replacement and / or cleaning of the filter 72 may not be required due to particles being in the filter 72. Filter 72 may be positioned and shaped in any suitable manner so that particles above a threshold size are suitably filtered from entering secondary loop 18 and removed therefrom by the flow of coolant in primary loop 16. Such particles flow through primary loop 16.

[0070] The size of the particles to be filtered may be determined based at least in part on the specifications of the low heat generating device (e.g., vehicle ECU 12). For example, filter 72 may be configured to filter particles having diameters greater than 500 μm, 300 μm, 100 μm, or 50 μm.

[0071] The flow controller 74 can control the relative flow rates of coolant in the primary loop 16 and the secondary loop 18. The flow rate of coolant in the primary loop 16 is typically greater than the flow rate of coolant in the secondary loop 18. For example, the flow rate of coolant in the primary loop 16 can be sufficiently greater than the flow rate of coolant in the secondary loop 18 such that particles filtered by the filter 72 are removed from the surface of the filter 72 by the flow rate of coolant in the primary loop 16.

[0072] The cooling system 5 can be designed such that a flow parallel to the surface of the filter 72 sweeps or removes particles from the surface that may block or clog the filter 72, thus eliminating or minimizing the need for any servicing or cleaning of the filter 72.

[0073] FIG. 8 is a schematic diagram of a fluid flow controller 80 in a cooling system 6, according to one embodiment. The cooling system 6 of FIG. 8 may have a similar overall structure as the cooling system 1 of FIG. 1. The cooling system 6 may include a flow path having a primary loop 16 and a secondary loop 18. The fluid flow controller 80 includes a speed regulating structure including a first flow control 82 and a second flow control 84. In some embodiments, the first flow control 82 may be located in the primary loop 16 at a location upstream of the inlet 18a of the secondary loop 18, and the second flow control 84 may be located in the primary loop 16 at a location between the inlet 18a and the outlet 18b of the secondary loop 18. In some implementations, the vehicle ECU 12 may be sensitive to particles in the coolant, for example, as described above. For example, the vehicle ECU 12 may be more sensitive to particles than a high heat generating device (e.g., a battery). In some embodiments, the fluid flow controller 80 may prevent or reduce the number of particles of at least a threshold size from entering the secondary loop 18. Fluid flow controller 80 may prevent or reduce the number of particles of a particular size from entering secondary loop 18 without blocking inlet 18a to secondary loop 18. In some embodiments, first flow control 82 and second flow control 84 may be implemented in accordance with any suitable principles and advantages of one or more of fluid flow controllers 30, 40, 50, 60.

[0074] Particles in the coolant flowing downstream of the first flow control 82 in the main loop 16 have a first velocity V1. Particles in the coolant flowing through the first flow control 82 in the main loop 16 have a second velocity V2. Particles in the coolant flowing through the second flow control 84 in the main loop 16 have a third velocity V3. Coolant flowing through the inlet 18a of the secondary loop 18 has a fourth velocity V4. The first flow control 82 can increase the velocity of the particles in the main loop 16 such that the second velocity V2 is greater than the first velocity V1.

[0075] In some embodiments, the first flow control portion 82 can include an opening that narrows the flow path of the coolant. For example, as shown in FIG. 8, an opening 86 that narrows the flow path of the coolant can be located on the lower side of the flow path (e.g., opposite the inlet 18a of the secondary loop 18). The primary loop 16 has a diameter d1, and the opening 86 has a diameter d2. The diameter d1 of the primary loop 16 can be larger than the diameter d2 of the orifice opening 86. The location of the opening 86, its diameter, and / or a higher fluid velocity V2 through the opening 86 can allow particles 88 in the coolant to continue flowing in the primary loop 16 without entering the secondary loop 18 due to their inertial forces.

[0076] In some embodiments, the second flow control section 84 can include a flow control that is the same as or substantially similar to the first flow control section 82. In some embodiments, the second flow control section 84 can include one or more of the fluid flow controllers 30, 40, 50, 60 of Figures 3-6B.

[0077] The size and location of the first flow control portion 82 may be selected based at least in part on one or more of the coolant flow rate, the physical properties of the coolant, and the size and / or density of the particles 88 to prevent or impede the particles 88 from entering the secondary loop 18. Such parameters may be adjusted to prevent or mitigate particles larger than a certain size from entering the secondary loop 18. The Stokes number is a dimensionless number that is widely used to describe the behavior of particles in a fluid flow, with a higher value indicating that the particle is more likely to break away from the fluid streamline due to its inertia.

[0078] A smaller diameter d2 of the openings 86 allows for a larger Stokes number and a larger pressure drop. Thus, the diameter d2 of the openings 86 can be tailored to a desired Stokes number and / or acceptable pressure drop. Coolant temperature and / or particle size can affect the velocity change of the particles 88 through the openings 86. The fin spacing or channel dimensions of the cooling solution for the vehicle ECU 12 can be determined at least in part based on the diameter of the particles that can flow through the openings 86 to the secondary loop 18 under the operating conditions of the coolant.

[0079] FIG. 9A is a schematic cross-sectional view of a fluid flow controller 90 in a cooling system 7, according to one embodiment. The cooling system 7 of FIG. 9A can have a similar overall structure as the cooling system 1 of FIG. 1. FIG. 9B is a schematic perspective view of the fluid flow controller 90 of FIG. 9A. The cooling system 7 can include a flow path having a main loop 16 and a secondary loop 18. The fluid flow controller 90 can include a turbulence generator, such as a centrifuge 92. FIG. 9C is a schematic perspective view of the centrifuge 92. In some embodiments, the centrifuge 92 can be located in the main loop 16 at a location upstream of the inlet 18a of the secondary loop 18. In some implementations, certain devices or components may be sensitive to particles in the coolant, for example, as described above. For example, a low heat generating device (e.g., a vehicle ECU) located in the secondary loop 18 may be more sensitive to particles than a high heat generating device (e.g., a battery) located in the main loop 16. In some embodiments, the fluid flow controller 90 can prevent or reduce the number of particles of a certain size from entering the secondary loop 18. In some embodiments, the centrifuge 92 may be welded to a portion of the main loop 16 .

[0080] The centrifugal separator 92 may include a helical structure that induces a helical flow in the coolant flowing through the main loop 16 to force particles in the coolant against the inner wall of the main loop 16. In some embodiments, the coolant flowing at or near the center of the main loop 16 may be free of particles. In some other embodiments, the coolant flowing at or near the center of the main loop 16 may have a relatively small number of particles. In some other embodiments, the coolant flowing at or near the center of the main loop 16 may have particles smaller than a certain size. The inlet 18a of the secondary loop 18 may be located at or near the center of the main loop 16. The coolant flowing at or near the center of the main loop 16 may enter the secondary loop 18. The location of the centrifugal separator 92 and the inlet 18a may prevent or reduce the number of particles of a certain size from entering the secondary loop 18. The diameter of the opening 18a may be determined at least in part based on the desired flow rate in the secondary loop 18 and the maximum size of particles allowed in the secondary loop 18.

[0081] FIG. 10A is a schematic cross-sectional view of a fluid flow controller 100 in a cooling system 8, according to one embodiment. The cooling system 8 of FIG. 10A can have a similar overall structure to the cooling system 1 of FIG. 1. FIG. 10B is a schematic perspective view of the fluid flow controller 100 of FIG. 10A. FIG. 10C is a schematic perspective view of a half of the fluid flow controller 100 of FIGS. 10A and 10B. The cooling system 8 can include a flow path having a primary loop 16 and a secondary loop 18. The fluid flow controller 100 can include a perforated plate 102. In some embodiments, the perforated plate 102 can be located in the primary loop 16 at a location upstream of the inlet 18a of the secondary loop 18. In some implementations, certain devices or components can be sensitive to particles in the coolant, for example, as described above. For example, a low heat generating device (e.g., a vehicle ECU) located in the secondary loop 18 can be more sensitive to particles than a high heat generating device (e.g., a battery) located in the primary loop 16. In some embodiments, the fluid flow controller 100 can prevent or reduce the number of particles of a particular size from entering the secondary loop 18 .

[0082] Each of the perforated plates 102 can include a number of pores capable of filtering particles larger than a certain dimension. In some embodiments, the perforated plates 102 can have different pore sizes. For example, the perforated plate 102 located downstream can have a larger pore size configured to filter larger particles, and the perforated plate 102 located upstream can have a smaller pore size configured to filter smaller particles. The perforated plate 102 can include openings 104. In some embodiments, the openings 104 of the perforated plate 102 can function the same as or substantially similar to the openings 86 of the first flow control portion 82 shown in FIG. 8. When the pores of the perforated plate 102 become clogged, the perforated plate 102 can function as a baffle to divert flow away from the inlet 18a of the secondary loop 18.

[0083] The fluid flow controllers 70, 80, 90, 100 shown in Figures 7-10C utilize fluid dynamics to control the flow of particles in the coolant in the primary and secondary loops 16, 18. Thus, the fluid flow controllers 70, 80, 90, 100 are passive fluid flow controllers. Compared to active flow restrictors, the passive fluid flow controllers disclosed herein may enable cooling systems that are simpler, more cost-effective, and / or consume less energy.

[0084] Although various embodiments are depicted in separate figures, any suitable principles and advantages disclosed herein may be implemented in combination or separately. For example, any one or more of the fluid flow controllers disclosed herein may be implemented in a single cooling system.

[0085] Unless the context clearly dictates otherwise, words such as "comprise," "comprising," "include," "including," and the like, throughout the specification and claims, should be construed in an inclusive sense, i.e., "including, but not limited to," as opposed to an exclusive or exhaustive sense. The term "connected," as generally used herein, refers to two or more elements that may be directly connected or connected by one or more intermediate elements. Similarly, the term "connected," as generally used herein, refers to two or more elements that may be directly connected or connected by one or more intermediate elements. Furthermore, the words "herein," "above," "below," and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above detailed description using singular or plural numbers may also include plural or singular numbers, respectively. The word "or" in connection with a list of two or more items covers any of the listed items, all of the listed items, and any combination of the listed items.

[0086] Additionally, conditional language as used herein, particularly "can," "could," "might," "may," "eg," "for example," "such as," and the like, is generally intended to convey that certain embodiments include certain features, elements and / or conditions while other embodiments do not, unless specifically stated otherwise or understood otherwise within the context in which it is used. Thus, such conditional language is generally not intended to imply that features, elements and / or conditions are in any way required for one or more embodiments.

[0087] The above description has been given with reference to specific embodiments. However, the above illustrative description is not intended to be exhaustive or to limit the invention to the precise form described. Many modifications and variations are possible in light of the above teachings. This will enable those skilled in the art to best utilize the techniques and various embodiments with various modifications suitable for various applications.

[0088] Although the present disclosure and embodiments have been described with reference to the accompanying drawings, various changes and modifications will become apparent to those skilled in the art. Such changes and modifications should be understood to be included within the scope of the present disclosure.

Claims

1. a flow path including a main path for cooling a first heat source and a secondary path for cooling a second heat source, the secondary path having an inlet and an outlet, the inlet in fluid communication with a first portion of the main path and the outlet in fluid communication with a second portion of the main path; a passive fluid flow controller disposed in the main pathway between the first and second portions and configured to adjust an amount of coolant in the flow path that is routed from the main pathway through an inlet of the secondary pathway to the secondary pathway; A cooling system comprising:

2. The cooling system of claim 1 , wherein the passive fluid flow controller comprises a plug and a spring.

3. The cooling system of claim 1 , wherein the passive fluid flow controller comprises an elastic band and a flexible tube.

4. The cooling system of claim 1 , wherein the passive fluid flow controller comprises one or more flaps coupled to an inner wall of the main passage.

5. The cooling system of claim 1 , wherein the passive fluid flow controller comprises a structure that expands and / or compresses in response to temperature changes to adjust an opening of the primary passage.

6. 2. An electric vehicle comprising: the cooling system according to claim 1; the first heat source cooled by the main path; and the second heat source cooled by the sub path, wherein the first heat source is a heat-generating device having a higher temperature and the second heat source is a heat-generating device having a lower temperature.

7. 7. The electric vehicle of claim 6, wherein the first heat source comprises a battery and the second heat source comprises a vehicle electronics system.

8. a flow path including a main path and a secondary path, the secondary path having an inlet and an outlet, the inlet in fluid communication with a first portion of the main path and the outlet in fluid communication with a second portion of the main path; a heat source coupled to the secondary path, the heat source having a channel that defines at least a portion of the secondary path; a fluid flow controller configured to prevent particles from entering the secondary passageway through an inlet of the secondary passageway, the particles having dimensions greater than dimensions of the heat source channel; and A system comprising:

9. The system of claim 8 , wherein the fluid flow controller comprises a filter configured to filter the particles.

10. The system of claim 8 , wherein the fluid flow controller is disposed in the main channel upstream of an inlet to the secondary channel.

11. The system of claim 10 , wherein the fluid flow controller is configured to increase the velocity of the particles.

12. The system of claim 10 , wherein the fluid flow controller is configured to filter the particles.

13. The system of claim 8 , wherein the fluid flow controller is configured to cause the particles to flow in the main channel past an inlet of the minor channel.

14. The system of claim 8 , wherein the heat source comprises an electronic system containing a cooling solution, the cooling solution comprising the channel.

15. An electric vehicle comprising: the system of claim 8; a vehicle electronics system cooled by the secondary path and including the channel and the heat source; and a battery cooled by the primary path.

16. 10. The system of claim 8, further comprising a passive fluid flow controller disposed in the main pathway between the first portion and the second portion and configured to regulate an amount of coolant routed from the main pathway through an inlet of the secondary pathway to the secondary pathway.

17. a flow path including a main path for cooling a first heat source and a secondary path for cooling a second heat source, the secondary path having an inlet and an outlet, the inlet in fluid communication with a first portion of the main path and the outlet in fluid communication with a second portion of the main path; a passive fluid flow controller configured to prevent particles in the coolant from entering the secondary channel via the secondary channel inlet such that the particles flow within the primary channel past the secondary channel outlet, the particles having a dimension greater than a threshold dimension; and A cooling system comprising:

18. The cooling system of claim 17 , wherein the passive fluid flow controller comprises a filter disposed on an inlet of the secondary path.

19. 20. The cooling system of claim 17, wherein the passive fluid flow controller comprises a structure in the main channel upstream of an inlet to the secondary channel configured to increase a velocity of the particles.

20. 18. An electric vehicle comprising: the cooling system according to claim 17; the first heat source cooled by the main path; and the second heat source cooled by the sub path, wherein the first heat source is a heat-generating device having a higher temperature and the second heat source is a heat-generating device having a lower temperature.

21. 21. The electric vehicle of claim 20, wherein the first heat source comprises a battery and the second heat source comprises a vehicle electronics system.

Images