TY - JOUR T1 - Optimal Control of Vortex Shedding Around Square Cylinder via Reduced Order Model TT - کنترل بهینه ریزش گردابه حول سیلندر مربعی شکل با استفاده از مدل رتبه کاسته JF - mdrsjrns JO - mdrsjrns VL - 13 IS - 5 UR - http://mme.modares.ac.ir/article-15-2145-en.html Y1 - 2013 SP - 49 EP - 62 KW - Optimal Control KW - Vortex Shedding KW - Suction and blowing N2 - In this paper, optimal control of vortex shedding behind square cylinder in laminar flow regime (Re=200) has been investigated. When Navier-Stokes equations are used as state equations, the discretization of the optimality system leads to large scale discretized optimization problems that represent a tremendous computational task. In order to reduce the number of state variables during the optimization process, a Reduced-Order Model (ROM) based on POD modes is derived to be used as state equations. Then, these equations are modified by introducing a Control Function to ROM in order to gain equations which are suitable for optimal control. Optimal trajectory for control input has been found by employment of Quasi-linearization which is one of the numerical methods for solving optimal control equations. The flow is actuated via suction and blowing slots. The results have been investigated in Results Section. Keywords: Optimal Control- Vortex Shedding- Suction and blowing- Reduced Order Model- POD modes- Quasi-linearization method. M3 ER -