Thermal management systems

Abstract

A heat transfer apparatus includes a plurality of “n” number of control valves, each of the plurality of “n” number of control valves including a control valve inlet and a control valve outlet; a like plurality of “n” number of evaporator sections, each of the like plurality of “n” number of evaporator sections including an evaporator section inlet and an evaporator section outlet, each evaporator section inlet fluidly coupled to a corresponding one of the plurality of “n” number of control valve outlets, each evaporator section configured to extract heat from at least one heat load that is in thermal conductive or convective contact or proximate to the evaporator section; a refrigerant fluid inlet fluidly coupled to the like plurality of evaporator sections; and a refrigerant fluid outlet fluidly coupled to the like plurality of evaporator sections.

What is claimed is: 
     
         1 . A heat transfer apparatus, comprising:
 a plurality of “n” number of control valves, each of the plurality of “n” number of control valves comprising a control valve inlet and a control valve outlet;   a like plurality of “n” number of evaporator sections, each of the like plurality of “n” number of evaporator sections comprising an evaporator section inlet and an evaporator section outlet, each evaporator section inlet fluidly coupled to a corresponding one of the plurality of “n” number of control valve outlets, each evaporator section configured to extract heat from at least one heat load that is in thermal conductive or convective contact or proximate to the evaporator section;   a refrigerant fluid inlet fluidly coupled to the like plurality of evaporator sections; and   a refrigerant fluid outlet fluidly coupled to the like plurality of evaporator sections.   
     
     
         2 . The heat transfer apparatus of  claim 1 , wherein the plurality of “n” number of control valves are fluidly coupled between the refrigerant fluid inlet and the evaporator outlets. 
     
     
         3 . The heat transfer apparatus of  claim 1 , wherein each of the plurality of “n” number of control valves is configured to receive a control signal. 
     
     
         4 . The heat transfer apparatus of  claim 1 , wherein the refrigerant fluid inlet comprises an inlet distributor having a plurality of outlets, with each of the plurality of outlets being coupled to the inlet of a corresponding one of the plurality of “n” number of control valves, and
 the refrigerant fluid outlet comprises an outlet collector having a plurality of inlets, with each of the plurality of inlets being coupled to the evaporator section outlet of a corresponding one of the like plurality of evaporator sections. 
 
     
     
         5 . The heat transfer apparatus of  claim 1 , wherein the plurality of “n” number of control valves are configured to selectively:
 expand a refrigerant fluid to generate a refrigerant fluid mixture comprising liquid refrigerant fluid and refrigerant fluid vapor; and 
 direct the refrigerant fluid mixture into the corresponding like plurality of evaporator sections. 
 
     
     
         6 . The heat transfer apparatus of  claim 5 , wherein the plurality of “n” number of control valves comprise expansion valves that are further configured to selectively stop a refrigerant fluid flow through the expansion valves. 
     
     
         7 . A method of cooling at least one heat load, comprising:
 providing a flow of a refrigerant fluid to a refrigerant fluid inlet of a heat transfer device;   providing the flow of the refrigerant fluid from the refrigerant fluid inlet to a plurality of “n” number of control valves, each of the plurality of “n” number of control valves comprising a control valve inlet and a control valve outlet;   providing the flow of the refrigerant fluid from the refrigerant fluid inlet to a like plurality of “n” number of evaporator sections, each of the like plurality of “n” number of evaporator sections comprising an evaporator section inlet and an evaporator section outlet, each evaporator section inlet fluidly coupled to a corresponding one of the plurality of “n” number of control valve outlets;   extracting heat, with at least one evaporator section, from at least one heat load that is in thermal conductive or convective contact or proximate to the evaporator section; and   providing the flow of the refrigerant fluid through a refrigerant fluid outlet fluidly coupled to the like plurality of evaporator sections.   
     
     
         8 . The method of  claim 7 , further comprising:
 expanding, in at least one of the a plurality of “n” number of control valves, the refrigerant fluid to generate a refrigerant fluid mixture comprising liquid refrigerant fluid and refrigerant fluid vapor; and   directing the refrigerant fluid mixture into the corresponding at least one evaporator section.   
     
     
         9 . The method of  claim 8 , further comprising selectively stopping the flow of the refrigerant fluid through the heat transfer device with the control valves. 
     
     
         10 . The method of  claim 7 , further comprising:
 directing the refrigerant fluid to enter a first set of “n”- “x” number of the plurality of evaporator sections over a first interval, while inhibiting the refrigerant fluid to enter a second, different set of “x” number of the plurality of evaporator sections over the first interval, where “n” is a total number of the plurality of evaporator sections; and   switching the refrigerant fluid to direct the transported refrigerant fluid that enters the gated evaporator to contact a third, different set of “n”- “x”′ number of the plurality of evaporator sections over a second, subsequent interval, while inhibiting the refrigerant fluid to enter a fourth, different set of “x”′ number of the plurality of evaporator sections over the second interval.   
     
     
         11 . A thermal management system, comprising:
 an open-circuit refrigeration system (OCRS), comprising:
 a receiver configured to store a refrigerant fluid; 
 at least one gated evaporator configured to extract heat from a plurality of heat loads when the plurality of heat loads are in thermal conductive or convective contact or proximate to the gated evaporator, with the gated evaporator comprising:
 a plurality of “n” number of control valves, each of the plurality of “n” number of control valves having a control valve inlet and a control valve outlet; and 
 a like plurality of evaporator sections, each of the like plurality of evaporator sections having an evaporator section inlet and an evaporator section outlet, with each evaporator section inlet coupled to a corresponding one of the plurality of “n” number of control valve outlets; 
 
   an exhaust line; and   a flow control device having an inlet and having an outlet, with the outlet coupled to an exhaust line, the flow control device configured to control a refrigerant fluid pressure upstream of the flow control device, with the receiver, the gated evaporator, the flow control device, and the exhaust line fluidly coupled to form an open-circuit refrigerant fluid flow path.   
     
     
         12 . The system of  claim 11 , further comprising an inlet distributor coupled to the outlet of the receiver, and having a plurality of outlets, with each of the plurality of outlets being coupled to the inlet of a corresponding one of the plurality of “n” number of control valves. 
     
     
         13 . The system of  claim 11 , further comprising an outlet collector having a plurality of inlets with each of the plurality of inlets being coupled to the evaporator section outlet of a corresponding one of the like plurality of evaporator sections, and having an outlet coupled to the inlet of the flow control device. 
     
     
         14 . The system of  claim 11 , wherein the plurality of “n” number of control valves are configured to selectively:
 expand the refrigerant fluid to generate a refrigerant fluid mixture comprising liquid refrigerant fluid and refrigerant fluid vapor; and 
 direct the refrigerant fluid mixture into the corresponding like plurality of evaporator sections. 
 
     
     
         15 . The system of  claim 14 , wherein the plurality of “n” number of control valves are expansion valves that are further configured to selectively stop refrigerant fluid flow through the expansion valves. 
     
     
         16 . The system of  claim 11 , wherein the plurality of “n” number of control valves are expansion valves that are not configured to stop refrigerant fluid flow through the expansion valves, with the system further comprising a plurality of solenoid control valves coupled to the expansion valves, the plurality of solenoid valves configured to selectively stop the refrigerant fluid flow through the expansion valves. 
     
     
         17 . The system of  claim 11 , wherein the plurality of “n” number of control valves are configured to selectively perform a constant-enthalpy expansion of a liquid refrigerant fluid to generate a refrigerant fluid mixture for the like plurality of evaporator sections. 
     
     
         18 . The system of  claim 11 , wherein the refrigerant fluid comprises ammonia. 
     
     
         19 . The system of  claim 11 , wherein the plurality of “n” number of control valves are further configured to control temperatures of the plurality of heat loads. 
     
     
         20 . The system of  claim 11 , wherein the flow control device comprises a back-pressure regulator connected downstream from the evaporator along the open-circuit refrigerant fluid flow path. 
     
     
         21 . The system of  claim 20 , wherein the back-pressure regulator is configurable to receive refrigerant fluid vapor generated in the gated evaporator and to regulate the pressure of the refrigerant fluid upstream from the back-pressure regulator along the refrigerant fluid flow path. 
     
     
         22 . The system of  claim 20 , wherein the back-pressure regulator is configurable to discharge the refrigerant vapor through the exhaust line, without returning the refrigerant vapor to the receiver. 
     
     
         23 . The system of  claim 11 , wherein the refrigerant fluid from the exhaust line is discharged so that the discharged refrigerant fluid is not returned to the receiver. 
     
     
         24 . The system of  claim 11 , further comprising a control system configured to respond to signals from at least one sensor to control operation of the plurality of “n” number of control valves. 
     
     
         25 . The system of  claim 24 , wherein the control system is configured to process the signals from the at least one sensor to switch “x” number of the plurality of “n” number of control valves to inhibit refrigerant flow through the “x” number of the plurality of “n” number of control valves during a period, with “x” having a value that is at least one less than “n”.” 
     
     
         26 . The system of  claim 24 , wherein the control system is configured to process signals that are time period signals to indicate that “x” number of uncooled evaporator sections have reached a maximum time period for a heat load operation, with “x” having a value that is at least one less than “n.” 
     
     
         27 . The system of  claim 24 , wherein the control system is configured to process signals that are temperature signals to indicate that “x” number of the uncooled evaporator sections have reached the maximum heat load temperature rise during a heat load operation, with “x” having a value that is at least one less than “n.” 
     
     
         28 . The system of  claim 24 , wherein the control system is configured to process signals that are temperature signals to indicate that “x” number of uncooled evaporator sections have reached a maximum evaporator section temperature rise during a heat load operation, with “x” having a value that is at least one less than “n.” 
     
     
         29 . The system of  claim 21 , wherein the flow control device is a first flow control device, and the system further comprises a second flow control device coupled between the receiver outlet and the inlet to the flow distributer, with the second flow control device configured to control vapor quality at the outlet of the gated evaporator. 
     
     
         30 . The system of  claim 21 , further comprising a closed-circuit refrigeration system (CCRS) integrated with the OCRS. 
     
     
         31 . The system of  claim 30 , further comprising a liquid separator having an inlet, a vapor-side outlet, and a liquid-side outlet. 
     
     
         32 . The system of  claim 31 , wherein the CCRS comprises:
 a compressor having a compressor inlet fluidly coupled to the vapor-side outlet and having a compressor outlet; and   a condenser having a condenser inlet fluidly coupled to the compressor outlet and having a condenser outlet coupled to an inlet of the receiver to condense a superheated refrigerant vapor at the condenser inlet by removing heat from the refrigerant fluid.   
     
     
         33 . The system of  claim 32 , further comprising a junction having an inlet fluidly coupled to the vapor-side outlet of the liquid separator and first and second outlets fluidly coupled to the compressor inlet and the inlet of the flow control device. 
     
     
         34 . The system of  claim 31 , further comprising:
 an electronically controllable expansion valve;   a sensor disposed downstream of the gated evaporator to generate a sensor signal that directly or indirectly controls the electronically controllable expansion valve.   
     
     
         35 . The system of  claim 31 , further comprising a recuperative heat exchanger that has a first fluid path that receives the refrigerant fluid from the receiver and a second fluid path that receives refrigerant vapor from the vapor-side outlet, with the second fluid path providing thermal contact between the refrigerant fluid leaving the receiver and the refrigerant vapor passing through the recuperative heat exchanger. 
     
     
         36 . The system of  claim 35 , wherein the recuperative heat exchanger evaporates any remaining liquid prior to being fed to the inlet of the compressor. 
     
     
         37 . The system of  claim 35 , further comprising:
 an electronically controllable expansion valve;   a sensor disposed downstream of the gated evaporator to generate a sensor signal that directly or indirectly controls the electronically controllable expansion valve, with the electronically controlled expansion valve operated with the sensor to maintain a superheat at an outlet of the recuperative heat exchanger.   
     
     
         38 . The system of  claim 37 , wherein the recuperative heat exchanger is configured to transfer heat energy from the refrigerant fluid emerging from liquid separator to refrigerant fluid upstream from the electronically controllable expansion valve. 
     
     
         39 . The system of  claim 31 , further comprising an ejector having a primary inlet, a secondary inlet, and an outlet, with the primary inlet fluidly coupled to receive refrigerant from the receiver, and the secondary inlet fluidly coupled to receive refrigerant fluid from the liquid-side outlet of the liquid separator. 
     
     
         40 . The system of  claim 39 , wherein the ejector is configured to pump a secondary refrigerant fluid flow received at the secondary inlet from the liquid side outlet using energy of a primary refrigerant flow from the receiver outlet. 
     
     
         41 . The system of  claim 31 , further comprising a pump having an inlet and an outlet, with the inlet fluidly coupled to the liquid-side outlet of the liquid separator and the outlet fluidly coupled to an inlet of the gated evaporator. 
     
     
         42 . The system of  claim 41 , wherein the pump is configured to circulate a refrigerant fluid flow received from the liquid-side outlet of the liquid separator to the inlet of the gated evaporator. 
     
     
         43 . The system of  claim 41 , further comprising a control system configured to control operation of the gated evaporator, the control system comprising a processor device, memory and storage operatively connected. 
     
     
         44 . The system of  claim 43 , wherein the control system is configured to:
 produce a first control signal to direct transported refrigerant fluid to enter a first set of fewer than the like plurality of evaporator sections over a first interval, and inhibits the refrigerant fluid to enter a second, different set of the fewer than the like plurality of evaporator sections over the first interval; and   produce a second control signal to direct the transported refrigerant fluid that enters the gated evaporator to contact a third, different set of the evaporator sections over a second, subsequent interval, and inhibits the refrigerant fluid to enter a fourth, different set of the fewer than the plural evaporator sections over the second interval.   
     
     
         45 . A thermal management method, comprising:
 transporting a refrigerant fluid from a receiver, through a gated evaporator having a plurality of evaporator sections configured to extract heat from a plurality of heat loads when the plurality of heat loads are in thermal conductive or convective contact or are in proximity to the gated evaporator, through a flow control device to control to control refrigerant fluid pressure upstream of the flow control device, and to an exhaust line of an open-circuit refrigeration system (OCRS);   directing the transported refrigerant fluid to enter a first set of “n”- “x” number of the plurality of evaporator sections over a first interval, while inhibiting the refrigerant fluid to enter a second, different set of “x” number of the plurality of evaporator sections over the first interval, where “n” is a total number of the plurality of evaporator sections;   switching the refrigerant fluid to direct the transported refrigerant fluid that enters the gated evaporator to contact a third, different set of “n”- “x”′ number of the plurality of evaporator sections over a second, subsequent interval, while inhibiting the refrigerant fluid to enter a fourth, different set of “x”′ number of the plurality of evaporator sections over the second interval; and   discharging refrigerant vapor that is generated by the plurality of heat loads from the exhaust line so that the discharged refrigerant vapor is not returned to the receiver.   
     
     
         46 . The method of  claim 45 , wherein the flow control device is a first flow control device, and the method further comprises controlling a vapor quality of the refrigerant fluid at an outlet of the gated evaporator by operation of a second flow control device. 
     
     
         47 . The method of  claim 45 , wherein switching occurs by controlling operation of a plurality of control valves coupled to a plurality of outlets of an inlet distributor of the gated evaporator, with the plurality of outlets being coupled to inlets of the plurality of evaporator sections. 
     
     
         48 . The method of  claim 45 , further comprising collecting refrigerant flows by an outlet collector having a plurality of inlets coupled to evaporator section outlets. 
     
     
         49 . The method of  claim 45 , further comprising:
 expanding, by the plurality of control valves, the refrigerant fluid to generate a refrigerant fluid mixture comprising liquid refrigerant and refrigerant vapor; and   directing the refrigerant fluid mixture into the corresponding evaporator sections.   
     
     
         50 . The method of  claim 49 , wherein the plurality of control valves are expansion valves that are configured to selectively stop refrigerant fluid through the expansion valves. 
     
     
         51 . The method of  claim 49 , wherein the plurality of “n” number of control valves are expansion valves that are not configured to stop refrigerant fluid through the expansion valves, and the method further comprises operating a plurality of solenoid control valves fluidly coupled to the expansion valves to selectively stop the refrigerant fluid through the expansion valves. 
     
     
         52 . The method of  claim 49 , wherein the plurality of control valves are configured to selectively perform a constant-enthalpy expansion of the liquid refrigerant fluid to generate the refrigerant fluid mixture for the evaporator sections. 
     
     
         53 . The method of  claim 45 , wherein the refrigerant fluid comprises ammonia. 
     
     
         54 . The method of  claim 45 , wherein the plurality of control valves are configured to control temperatures of the heat loads. 
     
     
         55 . The method of  claim 45 , wherein discharging comprises discharging the refrigerant vapor through a back-pressure regulator. 
     
     
         56 . The method of  claim 45 , wherein the back-pressure regulator is configured to receive refrigerant vapor generated in the gated evaporator and to regulate the pressure of the refrigerant fluid upstream from the back-pressure regulator. 
     
     
         57 . The method of  claim 45 , wherein the back-pressure regulator is configured to discharge the refrigerant vapor through the exhaust line without returning the refrigerant vapor to the receiver. 
     
     
         58 . The method of  claim 45 , wherein the refrigerant fluid from the exhaust line is discharged so that the discharged refrigerant vapor is not returned to the receiver. 
     
     
         59 . The method of  claim 45 , further comprising operating a control system to:
 respond to signals from sensors to control operation of the plurality of control valves; and   process the signals from the sensor to switch “x” number of the plurality of control valves to inhibit refrigerant flow through the “x” number of the plurality of control valves during the first interval, with “x” having a value that is at least one less than “n.”   
     
     
         60 . The method of  claim 59 , further comprising operating the control system to:
 process the signals as time period signals to indicate that “x” number of uncooled evaporator sections have reached a maximum time period for proper heat load operation, with “x” having a value that is at least one less than “n”.   
     
     
         61 . The method of  claim 59 , further comprising operating the control system to:
 process the signals as temperature signals to indicate that “x” number of the uncooled evaporator sections have reached the maximum heat load temperature rise during the heat load operation, with “x” having a value that is at least one less than “n.”   
     
     
         62 . The method of  claim 59 , further comprising operating the control system to:
 process the signals as temperature signals to indicate that “x” number of uncooled evaporator sections have reached a maximum evaporator section temperature rise during the heat load operation, with “x” having a value that is at least one less than “n.”   
     
     
         63 . The method of  claim 45 , wherein the flow control device is a first flow control device, and the method further includes controlling vapor quality at the outlet of the gated evaporator with a second flow control device fluidly coupled between the receiver outlet and the inlet to the flow distributer. 
     
     
         64 . The method of  claim 45 , wherein transporting the refrigerant fluid comprises transporting the refrigerant fluid through a closed-circuit refrigeration system (CCRS) that is integrated with the OCRS. 
     
     
         65 . The method of  claim 64 , further comprising transporting the refrigerant fluid through a liquid separator having an inlet, a vapor-side outlet, and a liquid-side outlet. 
     
     
         66 . The method of  claim 65 , further comprising:
 transporting the refrigerant fluid to a compressor of the CCRS, the compressor having a compressor inlet coupled to the vapor-side outlet and having a compressor outlet; and   transporting the refrigerant fluid to a condenser having a condenser inlet coupled to the compressor outlet and having a condenser outlet coupled to an inlet of the receiver to condense a superheated vapor at the condenser inlet by removing heat from the refrigerant fluid.   
     
     
         67 . The method of  claim 66 , further comprising receiving refrigerant fluid from the receiver by a recuperative heat exchanger that has a first fluid path that receives the refrigerant fluid from the receiver and a second fluid path that receives refrigerant vapor from the vapor-side outlet, with the second fluid path providing thermal contact between the refrigerant fluid leaving the receiver and refrigerant vapor passing through the recuperative heat exchanger. 
     
     
         68 . The method of  claim 67 , further comprising evaporating any remaining refrigerant liquid in the recuperative heat exchanger prior to the inlet of the compressor. 
     
     
         69 . The method of  claim 65 , further comprising transporting refrigerant fluid from the liquid side outlet of the liquid separator to a secondary inlet of an ejector that further has a primary inlet and an outlet, with the primary inlet fluidly coupled to receive refrigerant from the receiver, and the outlet fluidly coupled to deliver refrigerant fluid to the inlet of the liquid separator. 
     
     
         70 . The method of  claim 69 , further comprising pumping, with the ejector, a secondary refrigerant fluid flow received by the secondary inlet from the liquid side outlet using energy of a primary refrigerant flow from the receiver outlet. 
     
     
         71 . The method of  claim 65 , further comprising pumping, with a pump, refrigerant liquid from the liquid-side outlet of the liquid separator to an inlet of the gated evaporator.