Additively manufactured thermal energy storage units

Abstract

A thermal energy storage unit is arranged on a surface to be cooled or heated and includes a housing defining at least one flow path that extends along the surface, and at least one non-rectilinear structure that is arranged in the at least one flow path and has a plurality of substructures that are interconnected. The interconnected substructures define a plurality of exterior fluid channels external to the substructures and a plurality of interior cavities within the substructures. The exterior flow paths cross over or under the interior cavities. One of either the plurality of exterior fluid channels or the plurality of interior cavities is configured to contain a phase change material and the other of the plurality of exterior fluid channels and the plurality of interior cavities accommodates a heat transfer fluid that cross-flows the phase change material.

1 . A thermal energy storage unit arranged on a surface to be cooled or heated, the thermal energy storage unit comprising:
 at least one housing defining at least one flow path that extends along the surface; and   at least one non-rectilinear structure that is arranged in the at least one flow path and has a plurality of thermally conductive substructures, the substructures defining a plurality of interior cavities within the substructures and a plurality of exterior fluid channels that cross over or under the plurality of interior cavities,   wherein one of either the plurality of exterior fluid channels or the plurality of interior cavities is configured to contain a phase change material and the other of either the plurality of exterior fluid channels or the plurality of interior cavities accommodates a heat transfer fluid that cross-flows the phase change material.   
     
     
         2 . The thermal energy storage unit according to  claim 1 , wherein the at least one non-rectilinear structure has a shape that is conformal to the at least one housing. 
     
     
         3 . The thermal energy storage unit according to  claim 1 , wherein the at least one non-rectilinear structure is shellular in shape, whereby the non-rectilinear structure is gravity independent and gravitationally agnostic. 
     
     
         4 . The thermal energy storage unit according to  claim 1 , wherein the non-rectilinear structure is a hollow lattice, and each of the plurality of substructures has a hollow interior and a plurality of openings that are fluidly connected between the hollow interior and adjacent substructures. 
     
     
         5 . The thermal energy storage unit according to  claim 4 , wherein each of the substructures has an exterior surface that defines the hollow interior and tapers to each of the plurality of openings. 
     
     
         6 . The thermal energy storage unit according to  claim 5 , wherein the exterior surface is curved and non-planar. 
     
     
         7 . The thermal energy storage unit according  claim 4 , wherein the substructures are interconnected by tubular members connected between the plurality of openings. 
     
     
         8 . The thermal energy storage unit according to  claim 1 , wherein each of the substructures are identical in shape. 
     
     
         9 . The thermal energy storage unit according to  claim 1 , wherein the substructures have an ordered arrangement. 
     
     
         10 . The thermal energy storage unit according to  claim 1 , wherein the plurality of interior cavities are configured to contain the phase change material, and the phase change material is cross-flowed with a heat transfer fluid flowing through the plurality of exterior fluid channels. 
     
     
         11 . The thermal energy storage unit according to  claim 1  further comprising a plurality of housings that each include at least one non-rectilinear structure, wherein the plurality of housings are connected to each other to form the thermal energy storage unit, whereby the thermal energy storage unit is modular. 
     
     
         12 . A method of forming a thermal energy storage unit for a surface to be cooled or heated, the method comprising:
 using an additive manufacturing process to form at least one non-rectilinear structure having a plurality of thermally conductive substructures, the substructures defining a plurality of interior cavities within the substructures and a plurality of exterior fluid channels that cross over or under the plurality of interior cavities;   arranging the non-rectilinear structure in a housing defining at least one flow path that extends along the surface to be cooled or heated;   providing a phase change material in one of either the plurality of exterior fluid channels or the plurality of interior cavities; and   cross-flowing the phase change material with a heat transfer fluid.   
     
     
         13 . The method of forming the thermal energy storage unit according to  claim 12 , wherein using the additive manufacturing process includes using a 3D printing manufacturing process. 
     
     
         14 . The method of forming the thermal energy storage unit according to  claim 12 , wherein using the additive manufacturing process includes using a powder bed additive manufacturing process. 
     
     
         15 . The method of forming the thermal energy storage according to  claim 12  further comprising forming the at least one non-rectilinear structure to have a shape that is conformal to the housing. 
     
     
         16 . The method of forming the thermal energy storage unit according to  claim 12  further comprising forming each of the substructures to be identical in shape and in an ordered arrangement. 
     
     
         17 . The method of forming the thermal energy storage unit according to  claim 12  further comprising forming the non-rectilinear structure as a hollow lattice, and forming each of the plurality of substructures to have a hollow interior and a plurality of openings that are fluidly connected between the hollow interior and adjacent substructures. 
     
     
         18 . The method of forming the thermal energy storage unit according to  claim 17  further comprising forming each of the plurality of substructures to have an exterior surface that is non-planar and tapers to each of the plurality of openings. 
     
     
         19 . The method of forming the thermal energy storage unit according to  claim 12  further comprising:
 arranging the phase change material in the plurality of interior cavities; and 
 cross-flowing the phase change material with the heat transfer fluid through the external fluid channels. 
 
     
     
         20 . The method of forming the thermal energy storage unit according to  claim 12  further comprising:
 providing a plurality of housings; 
 forming a plurality of non-rectilinear structures that each have a plurality of thermally conductive substructures, wherein each of the plurality of non-rectilinear structures is arranged in a corresponding one of the plurality of housings; and 
 connecting the housings to each other to form the thermal energy storage unit, wherein the thermal energy storage unit is modular.