r sadeghi - Department of Mechanical Engineering, Eqbal Lahoori Institute of Higher Education, Mashhad, Iran
f pourtaghi - Department of Mechanical Engineering, Eqbal Lahoori Institute of Higher Education, Mashhad, Iran

In this study, the hydrodynamic modeling of air flow on the channel’s wall was performed using CFD based on finite volume method. A section of a canal that is a wall and has a cavity with a cross-section of a square of 3 cm, and in another case, we have a canal wall with an equilateral triangle cross-section with a length cm 3. In another case, a channel’s wall with an equilateral triangle with a length of 3 cm, exposed to the air flow, for the cross-section, is perpendicular to the side corresponding to the channel width and for the cross-section of the triangle, the vertex of the triangle is toward the air stream. This modeling is based on the dynamics of computational fluids and is carried out in two-dimensional systems in steady and transient systems in the range of 1.4 to 180 Reynolds. The modeling results are the speed contours that generate the sequence, and also predict critical Reynolds. In the critical Reynolds, the lines of the velocity around the canals are out of symmetry and, as Reynolds increases, this asymmetry is more evident. Critical Reynolds is obtained for a cylinder with a cross-section of the square is 36, and for a cylinder with a cross-section of the triangle 40. In addition, changes in lift and drag coefficients have been evaluated in different Reynolds.

Laminar flow, Triangular cylinder in cross flow, square cylinder in cross flow, finite volume method