Compact heat exchangers for gas purification heat recovery systems

Abstract

A heat exchanger includes an enclosure with distinct inlets and outlets for hot and cold fluids. The enclosure also houses a heat exchanger core, which includes a partition defining sets of hot and cold fluid channels. This partition features a common boundary between a cold fluid channel and a hot fluid channel facilitating heat exchange between the hot and cold fluids. The partition is designed such that at least some cold fluid channels exhibit variations in the common boundary's area per unit length along their extensions. These changes are designed to promote a predetermined and optimized heat exchange between the cold and hot fluids, increasing heat exchanger's efficiency and offering enhanced thermal performance in a compact and well-structured configuration.

What is claimed is: 
     
         1 . A heat exchanger comprising:
 an enclosure including
 a hot inlet for inflow of a hot fluid, 
 a hot outlet for outflow of the hot fluid, 
 a cold inlet for inflow of a cold fluid, and 
 a cold outlet for outflow of the cold fluid; and 
   a heat exchanger core including a plurality of partitions forming a set of hot fluid channels and a set of cold fluid channels,
 wherein each of the partitions is defined by a wall common to adjacent hot and cold fluid channels, the wall defining a continuous, thermally conductive boundary between adjacent hot and cold fluid channels to facilitate a heat exchange between a hot fluid and a cold fluid flowing within adjacent hot and cold fluid channels, and 
 wherein the plurality of partitions and the sets of hot and cold fluid channels define a three-dimensional lattice structure including multiple cells having a Y:X aspect ratio. 
   
     
     
         2 . The heat exchanger of  claim 1 , wherein the walls defining the partitions have a constant curvature along a length of the heat exchanger core. 
     
     
         3 . The heat exchanger of  claim 2 , wherein a curvature of the walls defining the partitions increases along a length of the heat exchanger core in a direction from the cold inlet to the cold outlet. 
     
     
         4 . The heat exchanger of  claim 1 , wherein a ratio between a cross-sectional area of the set of cold fluid channels and the set hot fluid channels is fixed along a length of the heat exchanger core. 
     
     
         5 . The heat exchange of  claim 1 , wherein a ratio between a cross-sectional area of the set of cold fluid channels and the set hot fluid channels changes along a length of the heat exchanger core. 
     
     
         6 . The heat exchanger of  claim 1 , wherein the cross-sectional area of the hot fluid channels is greater than the cross-sectional areas of the cold fluid channels. 
     
     
         7 . The heat exchanger of  claim 1 , wherein a Y:X aspect ratio of the multiple cells ranges from 1:1 to 4:1. 
     
     
         8 . The heat exchanger of  claim 1 , wherein a Y:X aspect ratio of the multiple cells increases along an extension of the heat exchanger core. 
     
     
         9 . The heat exchanger of  claim 1 , further comprising first and second regions including multiple cells having a first Y:X aspect ratio and a transition region disposed between the first and second regions, the transition region including multiple cells having a second Y:X aspect ratio. 
     
     
         10 . The heat exchanger of  claim 9 , wherein the second Y:X aspect ratio is greater than the first Y:X aspect ratio. 
     
     
         11 . The heat exchanger of  claim 1 , wherein the walls defining the plurality of partitions includes a roughness, wherein the roughness creates a turbulent flow within a fluid channel adjacent to the wall. 
     
     
         12 . The heat exchanger of  claim 1 , wherein the walls defining the plurality of partitions vary in at least one of a thickness and a material along a length of the heat exchanger. 
     
     
         13 . The heat exchanger of  claim 1 , further comprising a cold fluid outflow manifold for fluidly coupling the set of cold fluid channels and the cold outlet, the cold fluid outflow manifold having a cross-sectional area that is greater than a cross-sectional area of the cold outlet causing a temperature decrease of the cold fluid flowing within the cold fluid outlet. 
     
     
         14 . A gas purification system comprising a feed gas inlet, a purified gas outlet, a heater, a purifier, and at least one heat exchanger according to  claim 1 . 
     
     
         15 . The gas purification system of  claim 14 , including two or more heat exchangers, wherein the two or more heat exchangers are arranged in parallel. 
     
     
         16 . The gas purification system of  claim 14 , including two or more heat exchangers, wherein the two or more heat exchangers are arranged in series. 
     
     
         17 . A method of manufacturing a heat exchanger comprising:
 forming an enclosure and a heat exchanger core by an additive manufacturing process, the heat exchanger core including
 a plurality of partitions forming a set of hot fluid channels and a set of cold fluid channels, 
 wherein each of the partitions is defined by a wall common to adjacent hot and cold fluid channels, the wall defining a continuous, thermally conductive boundary between adjacent hot and cold fluid channels to facilitate a heat exchange between a hot fluid and a cold fluid flowing within adjacent hot and cold fluid channels, and 
 wherein the plurality of partitions and the sets of hot and cold fluid channels define a three-dimensional lattice structure including multiple cells having a Y:X aspect ratio, and 
 wherein an aspect ratio of the multiple cells in at least one region of the heat exchanger core is controlled during the additive manufacturing process to achieve a predetermined pressure drop for at least one of a hot fluid outlet or a cold fluid outlet of the heat exchanger. 
   
     
     
         18 . A heat exchanger including an enclosure, the enclosure comprising:
 a hot inlet for inflow of a hot fluid;   a hot outlet for outflow of the hot fluid;   a cold inlet for inflow of a cold fluid;   a cold outlet for outflow of the cold fluid; and   a heat exchanger core including a partition defining a set of hot fluid channels and a set of cold fluid channels, the partition including at least a boundary common to both the hot and the cold fluid channels, the common boundary being configured to facilitate a heat exchange between the hot fluid and the cold fluid,
 wherein at least one cold fluid channel from the set of cold fluid channels forms a set of branches within a region of the heat exchanger core and 
 a number of the branches of the at least one cold fluid channel is proportional to a decrease in a temperature difference between the cold fluid and the hot fluid within that region as compared to a temperature difference between the cold fluid at the cold inlet and the hot fluid at the hot outlet. 
   
     
     
         19 . The heat exchanger of  claim 18 , wherein at least one hot fluid channel from the set of hot fluid channels includes branches, each branch defining a segment of the at least one hot fluid channel, and wherein a number of segments of the at least one hot fluid channel increases along an length of the at least one hot fluid channel in a direction from the hot inlet to the hot outlet. 
     
     
         20 . The heat exchange of  claim 18 , wherein a cold fluid channel from the set of cold fluid channels, having a channel cross-sectional area, is configured to split into a first branch having a first branch cross-sectional area and a second branch having a second branch cross-sectional area, and wherein the channel cross-sectional area raised in a preset power is about equal to a sum of the first branch cross-sectional area raised in the preset power and the second branch cross-sectional area raised in the preset power.