Analysis of Non-Stochastic Lattice Structure Design for Heat Exchanger Applications

Abstract

MANOGHARAN, GUHA PRASANNA. Analysis of Non-Stochastic Lattice Structure Design for Heat Exchanger Applications. (Under the directions of Dr. Ola Harrysson and Dr. Denis Cormier.)

Non-stochastic lattice structures are cellular solids with periodically repeating array of cells formed by interconnected struts. Conventional manufacturing limits cellular solid structures to stochastic foams and honeycombs. The recent advancement of Solid Freeform Fabrication (SFF) enables the manufacturing of spatially controlled non-stochastic cellular solids engineered for the requirements of a particular application.

Recent developments led to the application of metal cellular solids for air heating applications. This research proposes to optimize the cellular solid structure design for efficient heat transfer with minimum fluidic pressure loss. The novel concept is to design cellular solids with thicker struts in the direction along the fluid flow and thinner struts perpendicular to the flow with appropriate current supply for optimum performance. The model analyzed has a resistive cellular solid at a fixed temperature. The geometries examined include hexagonal lattice and rhombic dodecahedron. The heat transfer can be enhanced by thicker struts in the core of the structures and subsequently, by increasing the current across the cells.

With corresponding experimental validation, the analysis indicates that by varying the cell length at the entry and exit along the flow direction, pressure loss can be significantly reduced. The pressure loss can be minimized by thinner struts in the entry and exit of the cellular solid. The study indicates that there is no significant effect of the angle between the edges on the performance of the system in the length scale considered.