0
research-article

Numerical Simulation of the Effect of Channel Orientation on Fluid Flow and Heat Transfer at High Buoyancy Number in a Rotating Two-Pass Channel with Angled Ribs

[+] Author and Article Information
Berrabah Brahim

Department of Mechanical Engineering, Materials and Reactive Systems Laboratory, Faculty of Technology, Djillali Liabes University, Sidi Bel-Abbes 22000, Algeria
Berrabah_brahim@yahoo.fr

Aminallah Miloud

Department of Mechanical Engineering, Materials and Reactive Systems Laboratory, Faculty of Technology, Djillali Liabes University, Sidi Bel-Abbes 22000, Algeria
aminallahm@yahoo.fr

1Corresponding author.

ASME doi:10.1115/1.4041797 History: Received September 18, 2017; Revised September 28, 2018

Abstract

Convective heat transfer in a rotating two-pass square channel with 45-deg ribs is numerically investigated to simulate turbine blade cooling operation under extreme design cooling conditions (high rotation number, high density ratio and high buoyancy number).Two channel orientations are examined 0-Deg and 45-Deg in order to determined the effets of passage orientation on flow and heat transfer. For a reference pressure of 10-atm and a Reynolds number of 25,000, the results show that at low buoyancy number and for both channel orientations, the combined effect of Coriolis and centrifugal buoyancy forces generates an important thermal gradient between low and high pressure surfaces of the first passage, while the second passage remains almost unchanged compared to the stationary cases. At high buoyancy number and unlike low buoyancy number, the interaction of Coriolis driven cells, rib-induced vortices and buoyancy driven cells is destructive, which degrades the heat transfer rate on trailing and leading surfaces in the first passage for 0-Deg. In contrast, for 45-Deg, this interaction is constructive, which enhances the heat transfer rate on co-trailing and co-leading surfaces. In the second passage, the interaction of rib-induced vortices and buoyancy driven cells deteriorates significantly the heat transfer rate in case of 0-Deg than in case of 45-Deg compared to low buoyancy number. The computations are performed using the second moment closure turbulence model and numerical results are in fair agreement with available experimental data.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In