Heat exchanger systems and methods

Abstract

Disclosed herein are heat exchanger system comprising: a refrigerant; a phase-changing material in thermal communication with the refrigerant; and a valve configured to selectively permit an amount of the refrigerant to flow through the heat exchanger system, the amount of the refrigerant being based on a temperature difference between the refrigerant and the phase-changing material. Also disclosed herein are methods of using the same.

What is claimed is: 
     
         1 . A heat exchanger system for use with a cooling system, the heat exchanger system comprising:
 a phase-changing material in thermal communication with a refrigerant flow path that is configured to permit refrigerant to flow therethrough; and   a valve configured to selectively permit an amount of the refrigerant to flow through the refrigerant flow path, the amount of the refrigerant being based on a temperature difference between the refrigerant and the phase-changing material.   
     
     
         2 . The heat exchanger system of  claim 1 , further comprising a controller in communication with the valve and one or more sensors, the controller being configured to:
 receive temperature data from the one or more sensors; and   control the valve based on the temperature data.   
     
     
         3 . The heat exchanger system of  claim 1 , wherein the phase-changing material has a melting point such that an absolute difference between the melting point of the phase-changing material and the median refrigerant temperature of the refrigerant is in the range from approximately 0° F. to approximately 10° F. 
     
     
         4 . The heat exchanger system of  claim 1 , wherein the valve has a degree of openness corresponding to the temperature difference between the refrigerant and the phase-changing material. 
     
     
         5 . The heat exchanger system of  claim 4 , wherein the valve has an open state and a closed state, and wherein the degree of openness is completely open in the open state and completely closed in the closed state. 
     
     
         6 . The heat exchanger system of  claim 5 , wherein the valve is configured to transition to the closed state when the median refrigerant temperature of the refrigerant and a temperature of the phase-changing material are substantially equivalent. 
     
     
         7 . The heat exchanger system of  claim 6 , wherein the valve is configured to transition to the open state when a difference between the temperature of the phase-changing material and the median refrigerant temperature of the refrigerant is greater than a predetermined threshold. 
     
     
         8 . The heat exchanger system of  claim 7 , wherein the degree of openness is proportional to the difference between the temperature of the phase-changing material and the median refrigerant temperature of the refrigerant. 
     
     
         9 . The heat exchanger system of  claim 1 , wherein the phase-changing material has a latent heat of fusion from 200 kJ/kg to 400 kJ/kg. 
     
     
         10 . A cooling system comprising:
 a refrigerant flow path;   a refrigerant configured to flow through the refrigerant flow path;   a compressor in fluid communication with the refrigerant flow path;   a condenser in fluid communication with the refrigerant flow path;   an evaporator in fluid communication with the refrigerant flow path;   a thermal expansion valve in fluid communication with the refrigerant flow path; and   a heat exchanger comprising:
 a phase-changing material in thermal communication with the refrigerant flow path, the phase-changing material being fluidly separated from the refrigerant; and 
 a valve configured to selectively permit an amount of the refrigerant to flow through the heat exchanger system, the amount of the refrigerant corresponding to a temperature difference between the refrigerant and the phase-changing material. 
   
     
     
         11 . The cooling of  claim 10 , further comprising a controller in communication with the valve and one or more sensors, the controller being configured to:
 receive temperature data from the one or more sensors; and   control the valve based on the temperature data.   
     
     
         12 . The cooling system of  claim 10 , wherein the phase-changing material has a melting point such that a difference between the melting point of the phase-changing material and the median refrigerant temperature is in the range from approximately 0° F. to approximately 10° F. 
     
     
         13 . The cooling system of  claim 10 , wherein the valve is configured to transition between a plurality of states. 
     
     
         14 . The cooling system of  claim 13 , wherein the plurality of states includes an open state, a closed state, and one or more intermediate states. 
     
     
         15 . The cooling system of  claim 14 , wherein the one or more intermediate states correspond to a difference between a temperature of the phase-changing material and a median refrigerant temperature of the refrigerant. 
     
     
         16 . The cooling system of  claim 14 , wherein the valve is configured to enter the closed state when a median refrigerant temperature of the refrigerant and a temperature of the phase-changing material are substantially equivalent. 
     
     
         17 . The cooling system of  claim 15 , wherein the valve is configured to transition to the open state when a difference between the temperature of the phase-changing material and the median refrigerant temperature of the refrigerant is greater than a predetermined threshold. 
     
     
         18 . A method of capturing cooling energy during partial-load cycles in a cooling system, the method comprising:
 responsive to a median refrigerant temperature of a refrigerant of the cooling system being less than a melting point of a phase-changing material, transitioning a valve to an open state such that the refrigerant can flow through a heat exchanger of the cooling system, thereby effecting heat transfer between the refrigerant and the phase-change material to cause the phase-changing material to become at least partially solidified; and   responsive to the phase-changing material reaching thermal equilibrium with the median refrigerant temperature of the refrigerant, transitioning the valve to a closed state.   
     
     
         19 . The method of  claim 18 , further comprising:
 responsive to the median refrigerant temperature of the refrigerant being greater than the melting point of the phase-changing material, transitioning the valve to the open state such that the refrigerant can flow through the heat exchanger, thereby effecting heat transfer between the refrigerant and the phase-change material to cause the phase-changing material to become at least partially melted; and   responsive to the phase-changing material reaching thermal equilibrium with the median refrigerant temperature of the refrigerant, transitioning the valve to the closed state.   
     
     
         20 . The method of  claim 18 , wherein the phase-changing material has a latent heat of fusion from 200 kJ/kg to 400 kJ/kg.