微通道冷凝器的相变换热仿真与结构优化设计

Phase Change Heat Transfer Simulation and Structural Optimization of Micro-channel Condenser

为改善微通道冷凝器制冷剂侧的流动均匀性,提高换热能力,以扁管插入深度、入口管插入深度和入口管位置等参数为设计变量,流动均匀性、压降和出口温度为目标,采用Optimate+模块对三维冷凝器模型进行多目标多参数优化。采用定向网格对扁管进行网格处理,提高了网格的精度和计算速度。以VOF模型和蒸发冷凝模型进行冷凝器整体相变仿真分析,研究制冷剂在流道中流动的不均匀现象。结构优化后,最终使冷凝器的出口温度降低1.7 K,压降减小39 kPa。

To improve the flow uniformity in the refrigerant side of micro-channel condenser and enhance its heat exchange capacity, the Optimate+module is adopted to conduct a multi-objective multi-parameter optimization on 3D condenser model, with the insertion depths of flat tubes and the insertion depth and position of inlet tube as design variables and the flow uniformity, pressure drop and outlet temperature as objectives. The directed mesh is used to discretize the flat tube model for raising the mesh accuracy and computation speed. A phase transition simulation is performed on the whole condenser with volume of fluid model and evaporation-condensation model to study the phenomenon of flow unevenness in refrigerant tube. The structural optimization finally leads to the lowering of outlet temperature by 1.7 K and a reduction of pressure drop by 39 kPa for the whole condenser.