热科学学报（英文版）2009，Vol.18Issue(2)：126-136,11.DOI:10.1007/s11630-009-0126-1
Prediction of Turbulent Flow Structure in a Fully Developed Rib-Roughened Narrow Rectangular Channel
Prediction of Turbulent Flow Structure in a Fully Developed Rib-Roughened Narrow Rectangular Channel
Md. Shafiqul IsIam 1M. Kaminaga 2R. Hino 2M. Monde3
作者信息
- 1. Atomic Energy Research Establishment, DEPZ-1359, Dhaka, Bangladesh
- 2. Japan Atomic Energy Agency (JAEA), Tokai 319-1195, Japan
- 3. Department of Mechanical Engineering, Saga University, Saga 840-8502, Japan
- 折叠
摘要
Abstract
Fully developed turbulent water-flow structure over one-side repeated-fibs in narrow two-dimensional rectangular channels was investigated experimentally by Particle Image Velocimetry (PIV) and analytically by the standard κ-εand nonlinear κ-ε turbulent models. Two fib-pitch to height ratios (p/k) of 10 and 20 were investigated while the rib height was held constant at 4 mm. The rib height-to-channel equivalent diameter ratio (k/De) was 0.1. The streamwise mean velocity and turbulent kinetic energy distributions at six selected axial stations from the center fib for the two Reynolds number (Re) of 7,000 and 20,000 were obtained and compared with the predicted one The performance ability in predicting separating and reattaching turbulent water-flow between the standard κ-ε and nonlinear κ-ε models had yielded no clear conclusion. A large-scale turbulent eddy was generated by the rib promoter and then propagated into the mainstream flow, which led to the deformation of the velocity profile. The turbulent kinetic energy was increased about two times higher at p/k = 20 than that at p/k =10 under the two Reynolds numbers. The effect of the p/k value and the Reynolds number (Re) on reattachment length (XR) was investigated and showed that the p/k and Re had no significant effect on the reattachment length beyond a critical value of Re = 15,000 where XR was found to be approximately 4 times of the rib height under water-flow condi-tion.关键词
Turbulent water-flow structure/repeated-ribs/narrow rectangular channels/two-dimensional analysis/reattachment lengthKey words
Turbulent water-flow structure/repeated-ribs/narrow rectangular channels/two-dimensional analysis/reattachment length分类
数理科学引用本文复制引用
Md. Shafiqul IsIam,M. Kaminaga,R. Hino,M. Monde..Prediction of Turbulent Flow Structure in a Fully Developed Rib-Roughened Narrow Rectangular Channel[J].热科学学报（英文版）,2009,18(2):126-136,11.
