Interactions between two flat plates at different positions in a current

Two-dimensional flow over two inclined flat plates in a staggered arrangement at low Reynolds numbers has been investigated by numerical simulation. The two flat plates with the same length d and thickness are modeled using the immersed boundary method. The spacing between the centers of the two plates in streamwise and transverse direction is in the range of s/d≤6.0 and t/d≤0.8, respectively, with one plate always located in the wake interference area of the other plate. The lift, drag, and moment coefficients are investigated systematically based on the variation of the spacing and the inclination angles of the two plates. The frequency domain was obtained through fast Fourier transform of the velocity component. The results show that, for cases with s/d<2.5, both of the plates are suffering significant effect due to the existing of the other plate. The drag and lift forces on the upstream plate decrease with 17% and 20%, while the drag and lift forces on the downstream plate decrease with 52% and 66%. For cases with s/d>2.5, the interaction to the upstream plate is smaller compared to the downstream plate, and new frequencies are exited in the wake of the second plate.