Multi-objective and multi-load topology optimization and experimental validation of homogenized coupled fluid flow and heat transfer and structural stiffness

Abstract

This work focuses on designing materials for elasticity and coupled fluid flow and heat transfer. The macroscale equations for homogenized elasticity and coupled fluid flow and heat transfer are presented. The topology optimization problem is formulated, its implementation detailed, and the design sensitivities of the homogenized coupled fluid flow and heat transfer problem deduced. Using the Method of Moving Asymptotes, bidimensional periodic cells are optimized for homogenized coupled fluid flow and heat transfer with a multi-load formulation, in which weights are assigned to the longitudinal and transverse components. The effect of the weighting parameter is discussed. A bidimensional periodic cell is optimized for longitudinal and transverse stiffness by means of a Multi-Objective Sequential Quadratic Programming method. The Pareto curve is presented, and the implementation details are discussed. The MOSQP is then used to perform multi-objective optimization of tridimensional cells for longitudinal homogenized coupled fluid flow and heat transfer and both components of homogenized transverse stiffness. Solutions are presented and compared for two Peclet numbers, for conductive and convective dominated regimes, respectively. Selected optimized geometries were produced and their thermo-hydraulic behavior was characterized in an experimental setup designed for this study. An experimental setup was assembled and tested in order to characterize the thermo-hydraulic behavior of periodic media subjected to forced convective heat transfer. Five samples were selected from the topology optimization results to be produced through additive manufacturing and subjected to thermo-hydraulic characterization. Each sample was tested for four mass flow rates and four heat fluxes.