와법을 이용한 원주군을 지나는 후류의 특성 계산

Abstract

Abstract: The Characteristics of the flow field through cylinders with in -line and staggered arrangements were calculated by vortex method. Vorte x distributions and velocity profiles around the cylinders with in-line and stagger ed arrangements were simulated at the pitch ratio of Pt/D=1.25~2.0 and Reynolds numb er of Re=4.0×10 1 ~4.0×10 4 . As the results the vortices of clockwise at the upper separation point cylinder and the vortices of anticlockwise at the lower s eparation point of each cylinder were generated at both in-line and staggered arrangeme nts. The generation of the reverse flow in the rear region of the cylinders was caused by the pitch ratio and Reynolds number, the boundary region was at the pitch ratio of Pt/D=1.5 and Reynolds number of Re=4.0×10 2 ~4.0×10 3 in case of in-line arrangement and was at the pitch ratio of Pt/D=1.4 and Reynolds number of Re=4.0 ×10 1 ~4.0×10 2 in case of staggered arrangement. Key words: Fluid mechanics, Numerical calculation, Vortex method, Unsteady flow, Cylinders