On the Applicability of a One-Dimensional Two-Fluid Flow Model to Simulation of Flows and Heat Transfer at Near- and Supercritical Pressures
For the purpose of simulating flows at near-and supercritical pressures, the one-dimensional separate two-fluid model (the six-equation model) of APROS process simulation software has been modified to allow calculation of transitions between the subcritical (two-phase) region and the supercritical pressure region, where the fluid stays in a single phase. This modification consisted of handling the liquid-to-supercritical-to-gas phase transition in a sound manner by introducing a numeric pseudo-phase-transition to the supercritical pressure region, and extending the constitutive equations to the supercritical pressures. In this paper, the results of the modification process are carefully evaluated paying special attention to the approach taken to handle the pseudo-phase transition. Validity of the implemented supercritical-pressure heat transfer correlations discussed, including the possibility to estimate the heat transfer coefficient in conditions characterized by presence of deteriorating phenomena. The approach taken to handle the pseudo-phase-transition is proved valid by ensuring the fulfillment of the conservation laws and comparing results with results from a one-phase solution. These are accomplished by calculating two fundamental test cases involving the pseudo phase transition. Possible limitations and short-comings of the model are indicated where appropriate.
System codes Thermal-hydraulics Supercritical pressures Code development SCWR
Joona Kurki Markku H(a）nninen
VTT Technical Research Centre of Finland Tietotie 3, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
国际会议
上海
英文
1494-1505
2010-10-10（万方平台首次上网日期，不代表论文的发表时间）