Experimental study on pressure drop characteristic of two-phase flow in reduced tee junction with flat tube

doi:10.11949/j.issn.0438-1157.20181171

Abstract

Abstract:

The pressure drop characteristic of two-phase flow in normal T-junction has been fully investigated. However, few articles focus on the pressure drop characteristics of the reduced T-junction with flat tube. In this paper, R134a were used as the work medium, and the experimental study on the pressure drop characteristics was carried out at the T-junction placed horizontally. Experimental results show that the existing pressure drop empirical correlations of microchannel were not able to predict the two-phase flow in microchannel flat tube frictional pressure drop accurately. Through fitting experimental data, the empirical correlation of frictional pressure drop for stratified flow with quality range of 0.01-0.45 and flow range of 0.7-3 g/s in microchannel flat tube is obtained, and the gas-liquid interaction coefficient C in Chisholm model was modified to predict the irreversible pressure drop of stratified flow with flow range of 1.1-5.3 g/s, quality range of 0.03-0.26 and separation ratio is 0.1-0.8 from header to flat tube.

摘要：

两相流在普通T型管中的压降特性已经得到充分研究，但是鲜有文献关注侧管为扁平管的T型管（扁平T型管）中的压降特性。以R134a作为工质，对水平放置扁平T型管进行了压降特性的实验研究。结果表明，现有的微通道摩擦压降经验关联式不能够准确预测两相流在微通道扁平管的摩擦压降。通过实验数据的拟合，得到了干度范围为0.01～0.45，流量范围为0.7～3 g/s的分层流在微通道扁平管中的摩擦压降经验关联式，并对Chisholm模型中气液两相相互作用系数C进行修改，使其能够预测主管进口流量在1.1～5.3 g/s，进口干度在0.03～0.26，流量分离比在0.1～0.8时的分层流从集管流入微通道扁平管时的不可逆压降。

CLC Number:

TQ028.8

XU Xiaoxiao, CHEN Long, XIAO Jiumin, LIU Chao. Experimental study on pressure drop characteristic of two-phase flow in reduced tee junction with flat tube[J]. CIESC Journal, 2018, 69(S2): 174-179.

徐肖肖, 陈龙, 肖久旻, 刘朝. 两相流在扁平T型管中压降特性的实验研究[J]. 化工学报, 2018, 69(S2): 174-179.

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