Numerical Study on Two-Phase Heat Transfer and Flow of Subcooled Flow Boiling of R290 in A Vertical Tube

Dengchen Qi ； Jiakai Zhang ； Wenzhong Gao

《World Scientific Research Journal》 6卷7期 (2020/07) Pp. 261-270

https://doi.org/10.6911/WSRJ.202007_6(7).0038

摘要

This study numerically investigates the two-phase heat transfer and flow of R290 during subcooled flow boiling in a vertical tube. The operation condition of the simulations is as follows: 500kg/m^2s for mass flux and 12kW/m^2 for heat flux. The simulations are carried out for 3D model using Fluent. The computations are based on two-fluid model combined with RPI wall boiling model. Main characteristics of subcooled flow boiling are analyzed, including vapor volume fraction, wall and bulk temperature, vapor and liquid velocity and heat transfer coefficient. The results show that heat transfer coefficient and wall temperature change significantly from single phase connective region to subcooled nuclear boiling region. The distributions of vapor volume fraction are different along axial and radial directions. There is a nearly constant trend for the rise of bulk temperature. Vapor velocity is lower than liquid velocity initially while exceed that finally.

關鍵字

Subcooled flow boiling ； two-phase flow ； heat transfer ； CFD

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