用户名: 密码: 验证码:
Large-eddy simulation of natural convection in an asymmetrically-heated vertical parallel-plate channel: Assessment of subgrid-scale models
详细信息查看全文 | 推荐本文 |
摘要
The performance of four different large-eddy simulation subgrid-scale models has been examined a posteriori for natural convection in an asymmetrically-heated vertical parallel-plate channel with a high aspect ratio. The compressible three-dimensional Favre-filtered mass, momentum and energy conservation equations have been closed using the Smagorinsky, dynamic, approximate localised dynamic and Vreman models. A two-stage predictor-corrector numerical methodology for low-Mach-number compressible flows was adopted to strongly couple the density with the Navier-Stokes equations. Based on the comparison with experimental data, it has been shown that the Smagorinsky model predicts inaccurate near-wall flow dynamics and delayed transitional behaviour while both dynamic procedures to compute the Smagorinsky model coefficient result in over prediction of wall temperatures, suggesting an under estimation of subgrid-scale dissipation. The time extrapolation procedure utilised in the approximate localised dynamic model has been shown to produce better adaptation towards the local flow behaviour when compared with the standard dynamic model. At the same time, time-averaged wall temperature and velocity field profiles have been well captured by the Vreman model, demonstrating its superiority when compared to the rest of the models.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700