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Abstract

Investigation is done on incompressible flow around circular cylinder with two passive controls. The first passive control has a cylinder type I, placed in front of the cylinder with a fixed distance. The second passive control investigated with two types are ellipse and circle, placed behind the cylinder at varying distances. Reynolds numbers used are 100, 500 and 1000. Variations of the passive control's shapes, the distance between the passive control and the cylinder, and the variation of the Reynolds number influence the drag coefficient received passive control. The smallest drag coefficient received passive control occurs in the Reynolds number 1000 and the distance T/D= 1.8. The drag coefficient received passive control ellipse or circular shape has very small difference, but for comparison investigation, passive control ellipse receives drag coefficient smaller than passive control circle shape.