Patent Application
20110073285
The present invention relates generally to fluid cooling systems employed with automotive vehicles.
A condenser, radiator, fan module (CRFM) for an automotive vehicle typically includes several separate heat exchangers for cooling fluids that flow through various vehicle subsystems. In more recent vehicles, such as hybrid vehicles, with an increase in the number of subsystems the number of cooling loops has increased, and thus the number of heat exchangers in the CRFM has also increased. Moreover, each of these heat exchangers is sized to meet the cooling requirements for its respective cooling loop under that particular loop's peak load conditions. These heat exchangers, then, take up more packaging space in the CRFM than is desired. Consequently, it is desirable to meet the peak cooling demands for each of the cooling loops while reducing the packaging space required for heat exchangers in the CRFM.
An embodiment contemplates a multi-zone cooling system for use in a vehicle. The cooling system may comprise a multi-zone heat exchanger, a first cooling loop and a second cooling loop. The multi-zone heat exchanger may have a first zone, a second zone and a third zone, a first one-way check valve between the first zone and the second zone configured to only allow fluid flow from the first zone to the second zone and a second one-way check valve between the third zone and the second zone configured to only allow fluid flow from the third zone to the second zone, a zone one fluid inlet, a zone one fluid outlet, a zone three fluid inlet, a zone three fluid outlet, a first zone two fluid outlet and a second zone two fluid outlet. The first cooling loop may include a first three-way valve having a first inlet for receiving fluid flow from the zone one fluid outlet, a second inlet for receiving fluid flow from the first zone two fluid outlet and a valve outlet, with the first three-way valve being controllable to selectively block fluid flow from one or the other of the first inlet and the second inlet. The second cooling loop may include a second three-way valve having a third inlet for receiving fluid flow from the zone three fluid outlet, a fourth inlet for receiving fluid flow from the second zone two fluid outlet and a valve outlet, with the second three-way valve being controllable to selectively block fluid flow from one or the other of the third inlet and the fourth inlet.
An embodiment contemplates a multi-zone cooling system for use in a vehicle that may comprise a multi-zone heat exchanger having a first zone, a second zone and a third zone; a first cooling loop that provides a flow of a fluid through a first vehicle component to cool the first vehicle component, with the first cooling loop configured to direct fluid flow from the first cooling loop into the first zone; a second cooling loop that provides a flow of the fluid through a second vehicle component to cool the second vehicle component, with the second cooling loop configured to direct fluid flow from the second cooling loop into the third zone; a first valve that selectively allows for fluid flow from one or the other of the first zone and the second zone into the first cooling loop; a second valve that selectively allows for fluid flow from one or the other of the third zone and the second zone into the second cooling loop; and a controller engaging the first and second valves to control switching of the first and second valves.
An embodiment contemplates a method of operating a multi-zone cooling system in a vehicle including a first cooling loop for providing cooling for a first vehicle component and a second cooling loop for providing cooling for a second vehicle component, the method comprising the steps of: (a) directing fluid flow from the first cooling loop into a first zone of a multi-zone heat exchanger and back into the first cooling loop from the first zone during a first operating condition for the first vehicle component; (b) directing fluid flow from the second cooling loop into a third zone of the multi-zone heat exchanger and back into the second cooling loop from the third zone during a first operating condition for the second vehicle component; (c) directing fluid flow from the first cooling loop into the first zone of the multi-zone heat exchanger, from the first zone to a second zone of the multi-zone heat exchanger and back into the first cooling loop from the second zone during a first cooling loop peak operating condition where peak cooling for the first vehicle component is needed; (d) while performing step (c), directing fluid flow from the second cooling loop into the third zone of the multi-zone heat exchanger and back into the second cooling loop from the third zone during the first operating condition for the second vehicle component; (e) directing fluid flow form the second cooling loop into the third zone of the multi-zone heat exchanger, from the third zone to the second zone of the multi-zone heat exchanger and back into the second cooling loop from the second zone during a second cooling loop peak operating condition where peak cooling for the second vehicle component is needed; and (f) while performing step (e), directing fluid flow from the first cooling loop into the first zone of the multi-zone heat exchanger and back into the first cooling loop from the first zone during the first operating condition for the first vehicle component.
An advantage of an embodiment is that a reduced number of heat exchangers is employed in the CRFM of the vehicle while still providing adequate cooling for peak cooling loads of the various cooling loops. This reduced number of heat exchangers may reduce the cost and improve the packaging of the CRFM in the vehicle.
An advantage of an embodiment is that two separate coolant loops using the same coolant and seeing peak loads typically under distinct operating conditions will operate through different zones of a single heat exchanger, with a shared zone that provides the additional cooling capacity to account for the distinct peak load conditions of the two loops. In effect, additional reserve cooling capacity is available for either loop when a high cooling load condition arises for one of the two loops, allowing for variable cooling capacity for each of these two loops. In effect, this one multi-zone heat exchanger acts as essentially four heat exchangers, while minimizing the packaging space.
An advantage of an embodiment may be that the use of the multi-zone heat exchanger may allow for a reduction in vehicle drag, a reduction in engine fan coolant pump power consumption, and a reduced overall pressure drop in the fluids across the CRFM.
Referring to
The multi-zone cooling system 26 includes a multi-zone heat exchanger 40 that may be contained in the CRFM 28 and is connected to two different cooling loops, a first cooling loop 42 and a second cooling loop 44. The first cooling loop 42 may be, for example, an internal combustion engine coolant loop and may contain a conventional type of coolant mixture, such as water and ethylene glycol. This coolant loop 42 may direct the coolant through, for example, an internal combustion engine 50 and an HVAC heater core (not shown). This cooling loop may be employed to cool a different component or subsystem, if so desired, such as, for example, a battery pack or battery related electronics components. The term “component” as used herein when referring to items cooled by the cooling loop includes a subsystem or subsystems and just refers to one or more items being cooled by the fluid in that particular loop. The first cooling loop 42 may include an electronically controllable pump 46 for pumping the coolant through the loop 42, and an electronically controllable 3-way valve 48 for redirecting the coolant flow through the loop 42.
The second cooling loop 44 may be a powertrain electronics cooling loop containing the same coolant mixture as the first cooling loop 42. This coolant loop 44 may direct the coolant through, for example, powertrain electronics such as a traction power inverter module 52. The second cooling loop 44 may include an electronically controllable pump 54 for pumping the coolant through the loop 44, and an electronically controllable 3-way valve 56 for redirecting the coolant flow through the loop 44. The valves 48, 56 may be separate from, mounted on or mounted in the multi-zone heat exchanger 40.
An electronic controller 58 may be connected to and control the operation of the pumps 46, 54 and the valves 48, 56 (as indicated by dotted lines in
The multi-zone heat exchanger 40 interacts with both the first and second cooling loops 42, 44. This heat exchanger 40 is a single heat exchanger that is divided up into three zones, a first zone 60, a second zone 62 and a third zone 64. The coolant in the heat exchanger 40 cannot flow from the first zone 60 into the second zone 62 except through a zone 1-2 one-way check valve 66, and cannot flow from the second zone 62 directly back into the first zone 60 (i.e., without flowing through the first cooling loop 42). The coolant in the heat exchanger 40 cannot flow from the third zone 64 into the second zone 62 except through a zone 3-2 one-way check valve 68, and cannot flow from the second zone 62 directly back into the third zone 64 (i.e., without flowing through the second cooling loop 44). In addition, the heat exchanger 40 does not allow for coolant flow directly between the first zone 60 and the third zone 64.
The multi-zone heat exchanger 40 also includes a zone one inlet 70 into the first zone 60 that receives fluid flow from the pump 46 in the first cooling loop 42, a zone one outlet 72 that directs fluid flow from the first zone 60 toward a first inlet of the 3-way valve 48 in the first cooling loop 42, and a first zone two outlet 74 that directs fluid flow from the second zone 62 toward a second inlet of the 3-way valve 48 in the first cooling loop 42. An outlet 76 from the 3-way valve 48 directs the fluid into the rest of the first cooling loop 42 (such as the internal combustion engine 50). Alternatively, the pump 46 may be located between the 3-way valve 48 and the internal combustion engine 50 rather than between the engine 50 and the zone one inlet 70, if so desired.
A zone three inlet 78 into the third zone 64 receives fluid into the third zone 64 from the pump 54 in the second cooling loop 44, a zone three outlet 80 directs fluid flow from the third zone 64 toward a first inlet of the 3-way valve 56 in the second cooling loop 44, and a second zone two outlet 82 directs fluid flow from the second zone 62 toward a second inlet of the 3-way valve 56. An outlet 84 from the 3-way valve 56 directs the fluid into the rest of the second cooling loop 44 (such as the traction power inverter module 52). Alternatively, the pump 54 may be located between the 3-way valve 56 and the traction power inverter module 52 rather than between the inverter module 52 and the zone three inlet 78, if so desired.
Thus, for fluid flow, the first zone 60 is always connected to the first cooling loop 42, the third zone 64 is always connected to the second cooling loop 44 and the second zone 62 may be connected to one of the first or second loops 42, 44 or to neither of the cooling loops. This allows for three distinct modes of coolant cooling for the multi-zone heat exchanger 40 as it interacts with the first and second cooling loops 42, 44.
The arrow heads on the fluid lines in
For operation of this multi-zone cooling system 26 in the vehicle 20, the first and second cooling loops will have the same coolant mixture and the peak load conditions of these loops will have little to no overlap (i.e., when one loop demands peak cooling capacity the other can be managed with a much more reasonable cooling capacity). In addition, while this embodiment has been discussed with two cooling loops interacting with the multi-zone heat exchanger 40, it is contemplated that another embodiment could have, for example, a third cooling loop and the addition of another zone, check valve, pump, 3-way valve and corresponding inlets and outlets from the heat exchanger 40.
While certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.
