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With the increasing thermal challenges of electronic equipment, topology optimization of heat sinks has aroused great research interest in recent years. However, most related researches deal with heat transfer problems of the laminar flow. Only several papers deal with heat transfer problems of the turbulent flow which exhibits better heat dissipation capacity. This paper intends to demonstrate the topology optimization of turbulent forced convective heat sinks with a computational-cheap multi-layer thermofluid model. Based on the assumption of a hydrodynamically fully developed turbulent flow, a single-layer flow model is derived from the 3D turbulent flow model. Viscous effects in the out-of-plane direction are modeled as the additional terms in the derived momentum and transportation equations. Similarly, based on the assumption of adaptive temperature profiles in the out-of-plane direction, heat fluxes between adjacent layers are modeled and a multi-layer heat transfer model is constructed. Further, the porosity field is introduced to describe the channel's topology and the corresponding topology optimization scheme is presented. Topology optimizations of a heat sink for coil-cooling are carried out to reduce the average temperature rise of the heat source under a maximum volume fraction constraint. The accuracy of the multi-layer model is evaluated via 3D thermofluid simulation of optimized and reference designs. Topology-optimized heat sinks exhibit better thermal performance and provide up to a 32.39% reduction of the average temperature rise, compared with the reference designs. Additionally, a comparative study is also provided between designs optimized in heat transfer problems under laminar and turbulent flows. [ABSTRACT FROM AUTHOR]

This paper investigates the topology optimization of planar cooling channels using a low-cost multilayer thermofluid model. A novel three-layer model including the upper/lower cover-plate layers and the central solid-fluid mixing layer is proposed. The flow boundary layer effect and the heat transfer effect in the thickness direction are modeled as the flow coupling and thermal coupling effects between adjacent layers, respectively. Particularly, in order to estimate more accurate temperature fields, the constructed three-layer heat transfer model in the solid-fluid mixing channel is derived based on the assumption of adaptive temperature profiles in the thickness direction. Further, based on the three-layer thermofluid model, the porosity field is introduced to describe the channel's topology, and the corresponding topology optimization scheme is presented. Several optimized channels under different constraints and boundary conditions are shown and discussed in comparison. Optimized channels show streamlined boundaries and reasonable layouts and exhibit competitive heat dissipation performance. Parametric studies are conducted to analyze the effectiveness and reliability of the topology optimization scheme. Further, to evaluate the accuracy and efficiency of the proposed three-layer model, optimized channels are simulated with the full 3D model and previous low-cost models. The proposed three-layer model exhibits good consistency with the full 3D model while achieves great improvement in efficiency. [ABSTRACT FROM AUTHOR]

With the increasing dissipated power levels of electronic equipment, heat sink design problems are significant aspects of some industrial design fields. Topology optimization theory has attracted much research interest in thermal-fluid problems to design high-performance heat sinks. These researches focus on optimizing the internal flow channel of heat sinks under predefined inlet and outlet schemes. However, inlet/outlet schemes also exhibit great influence on the performance of optimized heat sinks. This paper intends to demonstrate a concurrent optimization method of the internal flow channel, inlets, and outlets in forced convection heat sinks. The porosity field and moving morphable components (MMCs) are adopted to describe structural topologies of the internal channel design domain and the inlet/outlet design domains, respectively. The internal porosity field and the shape/position parameters of MMCs are applied as design variables. A conventional inlet/outlet component is presented and the corresponding topology description transformation function is constructed to convert the inlet/outlet topology into corresponding porosity fields. Further, the thermal-fluid coupling problems are solved through porosity-interpolated fluid flow and heat transfer governing equations. To ensure accurate inlet flow and temperature conditions during the topology iteration, continuous design-dependent inlet governing equations are established under inlet pressure, velocity, and flow flux boundary conditions. Design variables are concurrently optimized based on the sensitivity information. The proposed method is shown in detail by taking design problems of water-cooled heat sinks as examples. Various numerical examples are presented to validate the applicability and efficiency of this method. [ABSTRACT FROM AUTHOR]