Heat exchanger

Abstract

A heat exchanger (9) comprises a first conduit module (10a) for the flow of a first fluid, and a second conduit module (11a) for the flow of a second fluid. The second conduit module (11a) is fluidly isolated from the first conduit module (10a). The heat exchanger further comprises a first fluid flow path (12) for the flow of a third fluid in heat exchange with the first and second fluids. The first fluid flow path (12) extends in a substantially radial direction (13) of the heat exchanger (9). At least a portion of the first conduit module (10a) and at least a portion of the second conduit module (11a) are each arranged in a respective path that gradually widens or tightens about a longitudinal axis (14) of the heat exchanger (9). The first conduit module (10a) and the second conduit module (11a) are nested with one another.

1 . A heat exchanger comprising:
 a first conduit module for a first flow of a first fluid;   a second conduit module for a second flow of a second fluid, wherein the second conduit module is fluidly isolated from the first conduit module; and   a first fluid flow path for a third flow of a third fluid in heat exchange with the first and second fluids, wherein the first fluid flow path extends in a substantially radial direction of the heat exchanger;   wherein at least a portion of the first conduit module and at least a portion of the second conduit module are each arranged in a respective path that gradually widens or tightens about a longitudinal axis of the heat exchanger; and   wherein the first conduit module and the second conduit module are nested with one another.   
     
     
         2 . A heat exchanger as claimed in  claim 1 , wherein at least a portion of the first conduit module follows a first spiral path and at least a portion of the second conduit module follows a second spiral path. 
     
     
         3 . A heat exchanger as claimed in  claim 2 , wherein the first spiral path and/or the second spiral path comprises a plurality of straight sections and/or one or more curved sections. 
     
     
         4 . A heat exchanger as claimed in  claim 3 , wherein the first spiral path and/or the second spiral path is circular or elliptical or a polygon. 
     
     
         5 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module has an inner diameter and an outer diameter, and the second conduit module has an inner diameter and an outer diameter, wherein the inner diameter of the first conduit module is different to the inner diameter of the second conduit module and/or the outer diameter of the first conduit module is different to the outer diameter of the second conduit module. 
     
     
         6 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module comprises a first material and the second conduit module comprises a second material that is different to the first material. 
     
     
         7 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module comprises an inlet and an outlet, and the second conduit module comprises an inlet and an outlet, wherein the inlet of the first conduit module is spaced apart from the outlet of the first conduit module in the radial direction of the heat exchanger, and the inlet of the second conduit module is spaced apart from the outlet of the second conduit module in the radial direction of the heat exchanger. 
     
     
         8 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module comprises an inlet and an outlet, and the second conduit module comprises an inlet and an outlet, wherein the inlet of the first conduit module is spaced apart from the inlet of the second conduit module in the radial direction of the heat exchanger and/or the outlet of the first conduit module is spaced apart from the outlet of the second conduit module in the radial direction of the heat exchanger. 
     
     
         9 . A heat exchanger as claimed in  claim 1 , wherein the heat exchanger further comprises a third conduit module for a fourth flow of a fourth fluid in heat exchange with the third fluid, wherein the third conduit module is fluidly isolated from the first conduit module and the second conduit module, and wherein at least a portion of the third conduit module is arranged in a path that gradually widens or tightens about the longitudinal axis of the heat exchanger and is nested with the first and second conduit modules. 
     
     
         10 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module comprises a plurality of first tubes each wound in a respective path that gradually widens or tightens about the longitudinal axis of the heat exchanger and each spaced from one another in rows along the longitudinal direction of the heat exchanger, and wherein the second conduit module comprises a plurality of second tubes each wound in a respective path that gradually widens or tightens about the longitudinal axis of the heat exchanger and each spaced from one another in rows along the longitudinal direction of the heat exchanger. 
     
     
         11 . A heat exchanger as claimed in  claim 1 , wherein the heat exchanger comprises a plurality of the first conduit modules and a plurality of the second conduit modules, wherein at least a portion of each of the plurality of the first conduit modules and at least a portion of each of the plurality of the second conduit modules are nested with one another in an alternating manner. 
     
     
         12 . A heat exchanger as claimed in  claim 11 , wherein the plurality of the first conduit modules and the plurality of the second conduit modules are orientated such that their respective inlets and outlets are angularly spaced relative to one another. 
     
     
         13 . A heat exchanger as claimed in  claim 11 , wherein the heat exchanger further comprises a first inlet manifold in fluid communication with the inlets of each of the first conduit modules, a first outlet manifold in fluid communication with the outlets of each of the plurality of first conduit modules, a second inlet manifold in fluid communication with the inlets of each of the plurality of second conduit modules, and a second outlet manifold in fluid communication with the outlets of each of the plurality of second conduit modules. 
     
     
         14 . A heat exchanger as claimed in  claim 13 , wherein each of the first inlet manifold, the first outlet manifold, the second inlet manifold and the second outlet manifold is annular in shape. 
     
     
         15 . A heat exchanger as claimed in  claim 1 , wherein the heat exchanger further comprises one or more valves arranged within the first conduit module and/or the second conduit module, the one or more valves being configured to selectively reverse, stop or alter the first flow of the first fluid in the first conduit module and/or the second flow of the second fluid in the second conduit module. 
     
     
         16 . A heat exchanger as claimed in  claim 1 , wherein the first fluid is one of water, oil or refrigerant, wherein the second fluid is a different one of water, oil or refrigerant, and wherein the third fluid is air. 
     
     
         17 . A heat exchanger as claimed in  claim 1 , wherein the first conduit module contains the first fluid, the second conduit module contains the second fluid, and the first fluid flow path contains the third fluid. 
     
     
         18 . A vehicle, such as an aircraft, flying machine or automobile, comprising a heat exchanger as claimed in  claim 1 . 
     
     
         19 . A method of operating the heat exchanger as claimed in  claim 17 , the method comprising:
 heating or cooling the first fluid and heating or cooling the second fluid by causing the first fluid to flow through the first conduit module, the second fluid to flow through the second conduit module, and the third fluid to flow through the first fluid flow path.   
     
     
         20 . A method as claimed in  claim 19 , comprising providing a means for forcing the third fluid to flow through the first fluid flow path. 
     
     
         21 . A method of operating the heat exchanger as claimed in  claim 16 , wherein the first conduit module contains the first fluid, the second conduit module contains the second fluid, and the first fluid flow path contains the third fluid, the method comprising:
 heating or cooling the first fluid and heating or cooling the second fluid by causing the first fluid to flow through the first conduit module, the second fluid to flow through the second conduit module, and the third fluid to flow through the first fluid flow path; and   reversing or altering the direction of flow in one or more of the first conduit module, the second conduit module and the first fluid flow path.   
     
     
         22 . A method as claimed in  claim 21 , wherein the method further comprises stopping the flow in one of the first conduit module and the second conduit module while maintaining flow in the other of the first conduit module and the second conduit module and then subsequently starting the flow in said one of the first conduit module and the second conduit module. 
     
     
         23 . A method as claimed in  claim 21 , wherein the method further comprises operating the heat exchanger in one or more modes of operation, wherein in at least one of the modes of operation the flow in one or more of the first conduit module, the second conduit module and the first fluid flow path may be reversed or altered and/or the flow in one of the first conduit module and the second conduit module may be stopped.