Numerical simulation of flow past two circular cylinders in tandem and side-by-side arrangement at low Reynolds numbers

A numerical simulation was used to compare the characteristics of flows past two cylinders in tandem versus side-by-side arrangements. Numerical experiments were performed at various Reynolds numbers and with different distances between the two cylinders. Diverse characteristics of flow, such as drag force, vortex shedding, and pressure distributions were investigated here. In tandem arrangement, at a certain distance, the drag coefficients of both cylinders change abruptly. However, at other distances, the drag coefficients vary somewhat linearly with the distance between cylinders. In side-by-side deployment, when the distance is more than three times the cylinders’ diameter, the higher Reynolds number has a smaller drag coefficient (as in the case of a single cylinder). At points where the flow pattern, drag, and pressure coefficients change significantly, the critical spatial ratios between the two cylinders were determined at different Reynolds numbers. In addition to the study of such changes in flow characteristics, the effect of flow pattern on the pressure field and drag force coefficients, as well as their relationship, was also investigated.