Research On Topology Optimization Of Cooling Channels And Heat Sources Distribution For Liquid-cooled Heat Sink

Liquid-cooled heat sinks are widely used in many heat-generating devices,such as injection molds,large-scale integrated circuits,and battery packs of green car.The quality of the cooling system has a direct impact on the efficiency and service life of the equipment.Traditional cooling system design methods such as parametric optimization,and heuristic algorithm have the disadvantages of requiring pre-determined topological connection,and the inability to guarantee the reliability of the optimization results.Topology optimization is based on the simulation of physical fields to redistribute a finite amount of material within the design domain in order to minimize the objective function.Therefore.topology optimization enables both design freedom and design reliability.In this paper,the following works are carried out:1.Two-dimensional fluid-thermal coupling topology optimization based on moving morphable components method.To address the problems in the density method that absence of explicit geometric information,a two-dimensional fluid-thermal topology optimization method based on the component method is established for the first time,and a bendable component based on quadratic B-spline curve is proposed to describe the flow path.The method achieves better optimization results than the density method and can be combined with adaptive mesh refinement to improve the accuracy of flow simulation.2.Studying related problems of topology optimization on three-dimensional heat sinks.Aiming at the unreasonable wall-like fluid structure,we proposed that whether the solid domain is dominated by the heat conduction effect as a criterion for applicability of Brinkman equation.Numerical examples show that the Darcy number should be less than 10-7 to get reasonable results.In order to ensure the load-bearing capability of the heat sink and to avoid the impractical solid suspension structure in the 3D topology optimization,topology optimization method of the heat sink considering the load-bearing capability is established based on the density method.The typical structure in optimization results that with and without thermal expansion effects are summarized through numerical examples.In addition,a preliminary study on the design of cooling system for injection molding is carried out,and a simplified model is used to optimize the conformal flow channel for spherical products.3.A synergistic topology optimization method for cooling channels and heat source distribution.For the coupling effects of cooling channels and heat source locations in the optimal design of heat sink,a synergistic topology optimization method is established to describe the cooling channels by the density method and the heat source by the component method.For the problem of initial distribution dependence when multiple heat sources have different intensities,a heat source redistribution algorithm is proposed.It is shown that the established optimization method can optimize the design of heat sources and cooling channels quickly and efficiently,and a general criterion for multi-intensity heat sources is summarized,i.e.,high-intensity heat sources should be as close to the cooling inlet as possible.4.The development of the multi-physics topology optimization software on the OpenFOAM platform.The program currently supports multiple topology optimization methods,flow-thermal-structure topology optimization,massively parallel computing,and adaptive mesh refinement.