Numerical study on the laminar fluid flow characteristics around a rectangular cylinder with different width to height ratios

摘要

The present study numerically investigates laminar fluid flow past a rectangular cylinder with different width to height ratios. The mass and momentum conservation equations to govern the fluid flow around the rectangular cylinder are solved using the finite volume method which has the second order accuracy and the immersed boundary method is used to handle effectively the rectangular cylinder. The Reynolds number Re and the width to height ratio W/H are varied in the range of 50 ≤ Re ≤ 150 and 0.1 ≤ WIH ≤ 1, respectively. The distribution of the Strouhal number and the drag and lift coefficients strongly depend on the fluid flow and vortex structure around the rectangular cylinder varying as a function of the width to height ratio and the Reynolds number. The Strouhal number decreases monotonically with increasing width to height ratio in the Reynolds number varying in the range of 50 to 80. However, as the width to height ratio increases in the Reynolds number varying in the range of 90 to 150, the Strouhal number increases until it has a maximum value, followed by the decrease in its value.