Heat pump

Abstract

A heating or cooling device comprising a closed circuit wherein a fluid is continuously or intermittently circulated in one direction by a pump, the system including a body of macroporous, microporous or mesoporous solid through which the fluid circulates to create a temperature gradient.

1 . A heating or cooling device for air conditioning, refrigeration and heat pumping systems comprising a closed circuit wherein a fluid is continuously or intermittently circulated in one direction by a pump, the system including a heat transfer unit comprising a body of macroporous, mesoporous or microporous solid through which the fluid can circulate to create a temperature gradient. 
   
   
       2 . The device as claimed in  claim 1 , wherein the heat transfer unit further comprises a body of porous material having one or more inlet and outlet surfaces, means for supplying fluid to the inlet surface and means for removing fluid from the outlet surface, wherein a fluid supplied to the inlet surface passes through the body to the outlet surface. 
   
   
       3 . The device as claimed in  claim 2 , wherein the one or more of the inlet and outlet surfaces comprises a sorbent layer of liquid sorbent material. 
   
   
       4 . The device as claimed in  claim 3 , wherein a thermal conductivity of the sorbent layer in a direction of passage of the fluid is greater than the thermal conductivity perpendicular to the direction of passage of the fluid. 
   
   
       5 . The device as claimed in  claim 3 , wherein the thermal conductivity of the body of porous material in the direction of passage of the fluid is less than the thermal conductivity perpendicular to the direction of passage of the fluid. 
   
   
       6 . The device as claimed in  claim 2 , wherein the unit further comprises a laminate of a porous material between two layers of sorbent material. 
   
   
       7 . The device claimed in  claim 6 , wherein the sorbent material comprises elongated pieces of a thermally conductive material. 
   
   
       8 . The device as claimed in  claim 7 , wherein the thermally conductive material is a metal or graphite. 
   
   
       9 . The device as claimed in  claim 8 , wherein the thermally conductive material further comprises metal or graphite flakes or a mixture thereof. 
   
   
       10 . The device as claimed in  claim 2 , wherein the porous material comprises a mixture of sorbent material together with elongate pieces of thermally conductive material. 
   
   
       11 . The device as claimed in  claim 1 , wherein the macroporous, microporous or mesoporous solid is selected from materials having a mean pore size in a range of 100 μm to 0.5 nm. 
   
   
       12 . The device as claimed in  claim 1 , wherein the fluid is selected from: carbon dioxide, hydrofluorocarbons, hydrofluorocarbon ethers, hydrocarbons, hydrocarbon ethers, ammonia, water, nitrogen, inert gases or mixtures thereof. 
   
   
       13 . The device as claimed in  claim 12 , wherein the fluid is carbon dioxide. 
   
   
       14 . The device as claimed in  claim 1 , wherein there is substantially no absorption interaction between the fluid and the solid. 
   
   
       15 . The device as claimed in  claim 1 , wherein the system is a refrigerator or air conditioning system. 
   
   
       16 . The device as claimed in  claim 1 , wherein the system is a refrigerator comprising casing having inner and outer surfaces, the body of macroporous, microporous or mesoporous solid being disposed between the inner and outer surfaces so that the fluid circulating between the inner and outer surfaces passes through the said body. 
   
   
       17 . A casing for an electronic apparatus including a device as claimed in  claim 1 . 
   
   
       18 . A conduit for a fluid stream comprising a device as claimed in  claim 1 .