Passive Control of Hydrodynamic Forces on a Circular Obstacle in a Transient Flow: FEM Computations

Hydrodynamic forces are crucial in engineering applications; therefore, various research initiatives have been conducted to limit them. In this research, a passive control technique to investigate the fluid forces acting on a circular cylinder in a laminar flow regime is studied. The reliability of the usage of a splitter plate (passive control device) downstream of the obstacle in suppressing the fluid forces on a circular obstacle of diameter D = 0.1 is presented. The first parameter of the current study is the attachment of splitter plates of various lengths (L-i) with the obstacle, whereas the gap separation (G(i)) between the splitter plate and the obstacle is used as a second parameter. The control element of the first and second parameters are varied from 0.1 to 0.3 . For the attached splitter plates of lengths 0.2 and 0.3 , the oscillatory behavior of transient flow at R e = 100 is successfully controlled. For the gap separations 0.1 and 0.2 , the suppression of vortex shedding is also observed. However, it is observed that a splitter plate of too short length and a plate located at an inappropriate gap from an obstacle are worthless. Moreover, the present study is extended for power-law fluid in the same domain, and maximum drag reduction is achieved using the same strategy as for Newtonian fluid. The finite element method is utilized as a computational strategy for complicated nonlinear governing equations. For a clear physical depiction of the problem, velocity and pressure plots have been provided. It is concluded that the presence of a splitter plate has suppressed the vortex shedding and the flow regime turns out to be steady, as is evident from the nonoscillatory drag and lift coefficients.