微通道冷凝器的相变换热仿真与结构优化设计
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摘要
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 3 D 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.
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 3 D 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.
引文
[1] 王辉,汤勇,余建军.相变传热微通道技术的研究进展[J].机械工程学报,2010,46(24):101-106.
[2] TIAN Z,GU B,YANG L,et al.Performance prediction for a parallel flow condenser based on artificial neural network[J].Applied Thermal Engineering,2014,63(1):459-467.
[3] QI Z.Experimental investigation on minichannel parallel flow condenser performance with r22,R410A and R407C[J].International Journal of Refrigeration,2016,72:74-80.
[4] KWON B,MANISCALCO N I,JACOBI A M,et al.High power density air-cooled microchannel heat exchanger[J].International Journal of Heat & Mass Transfer,2018,118:1276-1283.
[5] 黄劲.车用微通道冷凝器流动及换热特性的研究[D].长春:吉林大学,2013,5.
[6] ZOU Y,TUE H,HRNIG P S.Modeling refrigerant maldistribution in microchannel heat exchangers with vertical headers based on experimentally developed distribution results[J].Applied Thermal Engineering,2014,64(1-2):172-181.
[7] ZOU Y,HRNJAK P S.Single-phase and two-phase flow pressure drop in the vertical header of microchannel heat exchanger[J].International Journal of Refrigeration,2014,44(7):12-22.
[8] HUANG L,LEE M S.A computational fluid dynamics and effectiveness-NTU based co-simulation approach for flow mal-distribution analysis in microchannel heat exchanger headers[J].Applied Thermal Engineering,2014,65:447-457.
[9] WANG T,GU B,WU B,et al.Modeling for multi-pass parallel flow condenser with the effect of refrigerant mal-distribution[J].International Journal of Refrigeration,2015,60(6):234-246.
[10] SHIBAHARA M,FUKUDA K,LIU Q S,et al.Single-phase convective heat transfer in a circular minichannel with unsteady thermal loads[J].Heat Transfer Research,2017,48(13):1179-1193.
[11] SORIANO G E,ZHANG T,ALVARADO J L.Study of the effects of single and multiple periodic droplet impingements on liquid film heat transfer[J].International Journal of Heat and Mass Transfer,2014,77:449-463.
[2] TIAN Z,GU B,YANG L,et al.Performance prediction for a parallel flow condenser based on artificial neural network[J].Applied Thermal Engineering,2014,63(1):459-467.
[3] QI Z.Experimental investigation on minichannel parallel flow condenser performance with r22,R410A and R407C[J].International Journal of Refrigeration,2016,72:74-80.
[4] KWON B,MANISCALCO N I,JACOBI A M,et al.High power density air-cooled microchannel heat exchanger[J].International Journal of Heat & Mass Transfer,2018,118:1276-1283.
[5] 黄劲.车用微通道冷凝器流动及换热特性的研究[D].长春:吉林大学,2013,5.
[6] ZOU Y,TUE H,HRNIG P S.Modeling refrigerant maldistribution in microchannel heat exchangers with vertical headers based on experimentally developed distribution results[J].Applied Thermal Engineering,2014,64(1-2):172-181.
[7] ZOU Y,HRNJAK P S.Single-phase and two-phase flow pressure drop in the vertical header of microchannel heat exchanger[J].International Journal of Refrigeration,2014,44(7):12-22.
[8] HUANG L,LEE M S.A computational fluid dynamics and effectiveness-NTU based co-simulation approach for flow mal-distribution analysis in microchannel heat exchanger headers[J].Applied Thermal Engineering,2014,65:447-457.
[9] WANG T,GU B,WU B,et al.Modeling for multi-pass parallel flow condenser with the effect of refrigerant mal-distribution[J].International Journal of Refrigeration,2015,60(6):234-246.
[10] SHIBAHARA M,FUKUDA K,LIU Q S,et al.Single-phase convective heat transfer in a circular minichannel with unsteady thermal loads[J].Heat Transfer Research,2017,48(13):1179-1193.
[11] SORIANO G E,ZHANG T,ALVARADO J L.Study of the effects of single and multiple periodic droplet impingements on liquid film heat transfer[J].International Journal of Heat and Mass Transfer,2014,77:449-463.