Analysis of Turbulent Natural and Mixed Convection Flows Using the v~2-f Model

摘要

The main objective of this work is to investigate the performance of the v~2-f model for the predictions of turbulent natural and mixed convection flows. For this purpose, a finite volume-based flow solver is developed for a collocated grid arrangement, and the v~2-f model is implemented for turbulence modeling. For natural convection flows, a tall cavity with the aspect ratio of 28.68 is selected as a test case. Mixed convection in a square cavity, ascending flow in a vertical pipe with constant wall flux, and fully developed mixed convection in a vertical channel are considered as test cases for buoyancy-driven mixed convection flows. To evaluate the performance of the v~2-f model, results obtained from the present study have been compared with the existing data of experimental studies or direct numerical simulations (DNS). Results obtained from two-equation models, viz., the RNG k-ε, realizable k-ε, and SST k-ω models are also presented for comparison. Overall, the v~2-f model predicts flow and heat transfer characteristics of natural and mixed convection flows satisfactorily.