Thermal management system

Abstract

A thermal management system for operating near a temperature T. The system includes a sheet-like spacer having a plurality of passageways. A degassed working fluid is disposed as a liquid within the passageways of the spacer. A flexible and substantially impermeable sheet-like envelope forms a sealed compartment enclosing the spacer and the degassed working fluid at an absolute pressure that is approximately equal to the vapor pressure of the working fluid at equilibrium with liquid phase of the working fluid at the temperature T. The spacer, the working fluid and the envelope form a sheet-like thermal management system. In some embodiments the spacer is a flexible spacer and the envelope is a flexible envelope and the sheet-like thermal management system is a flexible sheet-like management system. In some embodiments the envelope is a rigid structure.

1 . A thermal management system for operating near a temperature T, the system comprising:
 a substantially incompressible flexible sheet-like spacer having a plurality of passageways;   a working fluid having a liquid phase and a vapor pressure, wherein at least a portion of the working fluid is disposed within the passageways of the spacer;   a flexible and substantially impermeable sheet-like envelope that forms a sealed compartment enclosing the spacer and the working fluid at an absolute pressure that is approximately equal to the vapor pressure of the working fluid at equilibrium with liquid phase of the working fluid at the temperature T;   wherein the spacer, the working fluid and the envelope form a flexible sheet-like thermal management system.   
   
   
       2 . The thermal management system of  claim 1  wherein the spacer further comprises at least one material selected from the group consisting of spun fibers and bubble mat. 
   
   
       3 . The thermal management system of  claim 1  wherein the working fluid comprises a liquid that is degassed. 
   
   
       4 . The thermal management system of  claim 1  wherein the thermal management system further comprises a flexible sheet-like wick configured to transport liquid working fluid within the compartment. 
   
   
       5 . The thermal management system of  claim 1  wherein the thermal management system further comprises a sheet-like wick configured to transport liquid working fluid within the compartment. 
   
   
       6 . The thermal management system of  claim 1  wherein the envelope comprises aluminized polyester sheet material. 
   
   
       7 . The thermal management system of  claim 1  wherein the working fluid comprises a volume of water. 
   
   
       8 . The thermal management system of  claim 7  wherein the sheet-like package has a surface area referentially defined in units of cm 2 , and the volume of water is between approximately 0.10 and 2.60 cm 3  per cm 2  of surface area. 
   
   
       9 . The thermal management system of  claim 1  further comprising an element disposed in thermal contact with a portion of the envelope, the element selected from the group consisting of a heat sink and a heat source. 
   
   
       10 . A thermal management system for operating near a temperature T, the system comprising:
 a sheet-like spacer having a plurality of passageways;   a sheet-like wick disposed adjacent the spacer;   a working fluid having a liquid phase and a vapor pressure, wherein at least a portion of the working fluid is disposed as a liquid within the wick and disposed as a vapor in the passageways of the spacer;   a substantially impermeable sheet-like envelope that forms a sealed compartment enclosing the spacer and the working fluid at an absolute pressure that is approximately equal to the vapor pressure of the working fluid at equilibrium with liquid phase of the working fluid at the temperature T;   wherein the spacer, the wick, the working fluid and the envelope form a sheet-like thermal management system.   
   
   
       11 . The thermal management system of  claim 10  wherein the spacer further comprises at least one material selected from the group consisting of spun fibers and bubble mat. 
   
   
       12 . The thermal management system of  claim 10  wherein the working fluid comprises a liquid that is degassed. 
   
   
       13 . The thermal management system of  claim 12  wherein the working fluid comprises a volume of water and the sheet-like package has a surface area referentially defined in units of cm 2 , and the volume of water is between approximately 0.10 and 2.60 cm 3  per cm 2  of surface area. 
   
   
       14 . The thermal management system of  claim 10  further comprising an element disposed in thermal contact with a portion of the envelope, the element selected from the group consisting of a heat sink and a heat source. 
   
   
       15 . A thermal management garment system comprising:
 a sheet-like spacer having a plurality of passageways;   a working fluid having a liquid phase and a vapor phase, wherein at least a portion of the working fluid is disposed within the passageways of the spacer;   a flexible and substantially impermeable sheet-like envelope that forms a sealed compartment enclosing the spacer and the working fluid at a temperature and pressure where the liquid phase and the vapor phase are near equilibrium; wherein   the thermal management garment system is configured to conform to a human body and transfer heat to or from portions of the body.   
   
   
       16 . The thermal management garment system of  claim 15  further comprising a retaining portion for receiving a heat source for heating the wearer. 
   
   
       17 . The thermal management garment system of  claim 16  wherein the garment system has an upper portion and lower portion and the heat source is positioned in the lower portion. 
   
   
       18 . The thermal management garment system of  claim 15  further comprising a retaining portion for a heat sink for cooling the wearer. 
   
   
       19 . The thermal management garment system of  claim 18  wherein the garment system has an upper portion and a lower portion and the heat sink is positioned in the upper portion. 
   
   
       20 . The thermal management system of  claim 15  further comprising an element disposed in thermal contact with a portion of the envelope, the element selected from the group consisting of a heat sink and a heat source. 
   
   
       21 . A method of fabricating a thermal management system, the method comprising the steps:
 (a) disposing a spacer in a compartment of a substantially impermeable envelope having a port that provides a passageway having at least one channel for transporting at least one fluid into and out from the compartment;   (b) adjusting the air pressure in the compartment through the passageway in the port;   (c) injecting a degassed working fluid into the compartment through the passageway in the port; and   (d) closing the passageway.   
   
   
       22 . The method of  claim 21  wherein step (c) comprises injecting a working fluid at its boiling temperature through the port. 
   
   
       23 . A method of fabricating a thermal management system, the method comprising:
 (a) disposing a spacer in a substantially impermeable envelope having a compartment;   (b) disposing a frangible pouch containing a working fluid in the compartment;   (c) adjusting the air pressure in the compartment;   (d) sealing the compartment of the envelope; and   (e) breaking the frangible pouch to release the working fluid inside the compartment.