Phase-change material heat exchanger

Abstract

A phase-change material heat exchanger includes a frame configured to define a chamber therein and house a first fluid, the first fluid being water. At least one heat exchange element is configured to have a second fluid pass through an interior of the heat exchange element, the at least one heat exchange element moveably retained within the chamber. When the second fluid passes through the heat exchange element at a first temperature, the first fluid changes from a liquid to a solid, and the second fluid exits the heat exchange element at a second temperature that is higher than the first temperature.

What is claimed is: 
     
         1 . A phase-change material heat exchanger comprising:
 a frame configured to define a chamber therein and house a first fluid, the first fluid being water; and   at least one heat exchange element configured to have a second fluid pass through an interior of the heat exchange element, the at least one heat exchange element moveably retained within the chamber;   wherein when the second fluid passes through the heat exchange element at a first temperature, the first fluid changes from a liquid to a solid, and the second fluid exits the heat exchange element at a second temperature that is higher than the first temperature.   
     
     
         2 . The heat exchanger of  claim 1 , wherein the at least one heat exchange element includes a plurality of surface area structures on an exterior surface thereof. 
     
     
         3 . The heat exchanger of  claim 2 , wherein the plurality of surface area structures are at least one of fins and pins. 
     
     
         4 . The heat exchanger of  claim 1 , wherein the at least one heat exchange element has a plate configuration. 
     
     
         5 . The heat exchanger of  claim 1 , wherein the at least one heat exchange element is configured to define a freeze front of the first fluid along an exterior surface of the at least one heat exchange element. 
     
     
         6 . The heat exchanger of  claim 1 , wherein the second fluid is an operating fluid for a high powered laser. 
     
     
         7 . The heat exchanger of  claim 1 , wherein the frame defines a tapered shape with a bottom of the frame being narrower than a top of the frame. 
     
     
         8 . The heat exchanger of  claim 1 , further comprising at least one expansion element configured to support the at least one heat exchange element within the chamber. 
     
     
         9 . The heat exchanger of  claim 8 , wherein the at least one expansion element is a spring. 
     
     
         10 . The heat exchanger of  claim 1 , further comprising a membrane retained about the frame and configured to expand when the first fluid changes from a liquid to a solid. 
     
     
         11 . The heat exchanger of  claim 1 , wherein the at least one heat exchange element comprises a first support and a second support, with a body extending between the first support and the second support. 
     
     
         12 . The heat exchanger of  claim 1 , further comprising an enclosure, wherein the enclosure includes the frame and at least a portion of the enclosure is configured to expand in response to water freezing. 
     
     
         13 . A method of using a phase-change material heat exchanger, the method comprising:
 conveying an operating fluid at a first temperature through at least one heat exchange element, the at least one heat exchange element disposed within a chamber of a phase-change material heat exchanger, the chamber filled with water;   causing the water to phase change from a liquid to a solid within the chamber; and   conveying the operating fluid out of the at least one heat exchange element at a second temperature that is higher than the first temperature.   
     
     
         14 . The method of  claim 13 , the method further comprising conveying the operating fluid through the at least one heat exchange element at a third temperature when the chamber is filled with ice. 
     
     
         15 . The method of  claim 14 , wherein the third temperature is a temperature sufficiently high to phase change the ice to liquid water when passing through the at least one heat exchange element. 
     
     
         16 . The method of  claim 13 , further comprising forming a freeze front progression within the chamber such that a volumetric expansion of the water when freezing does not damage the phase-change material heat exchanger.