MODULES
Mixed Convection Over A 2-D Square Cylinder
Problem Definition:
This test case is for solving a mixed convective flow around bluff bodies. The physical geometry of the problem considered is shown in Fig.7.1.A fixed two-dimensional square cylinder with side B = 1 is heated or cooled to a constant temperature TW = 1. This cylinder is exposed to a constant free-stream upward velocity and temperature fields represented by vf = 1 and Tf = 0 respectively. In order to make the problem computationally feasible, artificial confining boundaries are placed around the flow, where free-slip boundary conditions are applied. The blockage ratio ( i.e. the ratio of the width of the cylinder B to the horizontal distance between the left and right artificial boundaries, L) is taken as 1/30.The total non-dimensional vertical length of the computational domain is taken as 40 where the distance between the inlet plane and the bottom surface of the cylinder, HU, and the distance between the top surface of the cylinder and the exit plane, HD, are taken as 5 and 34 respectively.
The Reynolds number, Prandtl number and Richardson number are 100, 0.7, 1.0
respectively. Most of the researchers solved this type of problem by using non-dimensional governing equations. In order to compare the present results with Sharma et al. [1], the fluid and thermodynamic properties are chosen as follows:
Figure 7.1: Mixed convection over square cylinder
Table 6.1 shows the comparison of different parameters obtained in the present case with published results which shows a reasonably good match.
Figure 7.3: Isotherms near the cylinder at Ri=1.0
Figure 7.2: Streamlines near the cylinder at Ri=1.0
Figure 6.4: Temporal variation of lift coefficient at Ri=1.0
Figure 6.5: Temporal variation of drag coefficient at Ri=1.0
Table 6.1: A comparison of different parameters with Sharma et al. [1]
