Numerical study of laminar flow in a sudden expansion obstacled channel

Abstract

In the present work, a numerical study has been conducted to investigate the flow heat transfer through an obstacled sudden expansion channel. Rectangular adiabatic obstacles mounted behind the expansion region on the upper and lower wall of the channel used. The effects of obstacles length, obstacles thickness and number of obstacles on flow and thermal fields for different Reynolds number and expansion ratio examined. Three values of expansion ratio (ER) equal to 1.5, 1.75 and 2 were used. The choice of values of Reynolds number takes in consideration the symmetry state. The governing equations of continuity, momentum and energy discretized by using the finite difference formulation and the resulting algebraic equations solved by using Gauss-Seidle iteration method. The obtained results show that the obstacles have a considerable effect on dynamics of the flow and enhancement of heat transfer. In addition, it is found that the heat transfer is enhanced more as the obstacles thickness increases and this trend is decreased as the obstacles length increases.

Keywords

Dates

  • Submission Date2012-10-29
  • Revision Date2013-07-20
  • Acceptance Date2013-07-22
  • Online Date2013-08-17

DOI Reference

10.2298/TSCI121029105M

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