摘要
本文建立三维模型并模拟了管壳式蒸发器内制冷剂R410A的流动分配情况,通过计算支管的相对标准方差,系统地研究了蒸发器结构和入口参数对制冷剂均分性能的影响。结果表明,蒸发器的结构参数、入口参数和入口管箱结构使流体均分呈现不同的变化规律。不均匀度随支管总流通面积的减小而显著降低,而管箱尺寸的影响较为有限;根据流场特点优化入口管箱结构可减小涡流区和压力分布不均,使不均匀度降低15.8%~36.5%,并提升制冷剂均分性能;同时,入口流速增大会导致流体分配出现恶化,不均匀度随入口干度的提高略微下降并达到平稳,而且最大降幅不超过4%。
A three-dimensional model is established to simulate the flow and distribution of R410 A in the shell and tube evaporator in this paper.The effects of evaporator structure and inlet parameters on the performance of refrigerant distribution are studied systematically by calculating the relative standard deviation of the branches.The results show that the structure parameters,inlet parameters and the entrance box structure of evaporator make the fluid distribution change differently.The unevenness has declined evidently with the decrease of the total flow area of branch pipes,while the influence of the size of pipe box is limited.According to characteristics of the flow field,optimizing the structure of entrance box is helpful to narrow the eddy current area and pressure maldistribution.The unevenness is reduced by 15.8%-36.5%and the refrigerant distribution is improved.Besides,the increase of inlet velocity leads to the deterioration of fluid distribution.The maximum decrease of unevenness is less than 4%and the unevenness gradually achieves stability with the increase of the inlet dryness.
作者
宋哲
许波
陈振乾
SONG Zhe;XU Bo;CHEN Zhenqian(School of Energy and Environment,Southeast University,Nanjing 210096,Jiangsu,China)
出处
《制冷技术》
2021年第5期45-51,共7页
Chinese Journal of Refrigeration Technology
关键词
流动
均匀分配
不均匀度
数值模拟
Flow
Uniform distribution
Unevenness
Numerical simulation
