Numerical Investigation of Flow Boiling Characteristics Using Two-Fluid Eulerian CFD Model in Narrow Rectangular Channel
Narrow channel heat exchange technology is one of the key technologies for the develop-ment of integrated small modular reactors(SMR),since the flow boiling heat transfer in the narrow channel has the potential to result in higher heat transfer efficiency and more compact structure for the heat exchangers in SMR.The'wall heat flux partitioning'(WHFP)model in conjunction with an Eulerian-Eulerian Multiphase Flow(EEMF)method is found to be an apartment tool for two-phase hydrothermal analysis.In this paper,the accuracy of the EEMF-WHFP is evaluated over a large database of boiling flows in a narrow rectangular channel,avoiding the rather popular case-by-case tuning of descriptive models to a limited number of experiments.In this paper,the effects of different sub-models(including bubble departure diameter dw and nucleation site density Nw)on bubble parameters,heat transfer and flow field prediction in flow boiling are systematically analyzed.Based on the selection of different sub-model under the simulation results,an optimized combination of bubble parameter sub-models suitable for flow boiling in rectangular narrow channels with a wide range of working conditions is proposed.The conclusions can provide reference for the design and calculation of reactor heat exchange elements and compact heat exchangers.
narrow rectangular channelflow boilingCFDwall boiling model
NETL
NSTL
万方数据
