Abstract
The Taylor-Couette (TC) flow holds many industrial applications. The flow dynamics between two independently rotating concentric cylinders is governed by the parameters such as the angular velocity ratio (μ = Ωo/Ωi), the radii ratio (η = R1/R2), and Reynolds number (Re). The non modal stability analysis is an important tool to analyse the time evolution of disturbances, occuring due to non-normality of the operators governing the behaviour of perturbations, in order to understand the transition mechanism in a fluid flow 1. In this work, we have studied the linear stability of the TC flow for different cases of radii ratio (η = 0.1, 0.25, 0.5, 0.75) and angular velocity ratio (μ = −1, 0). Further we have applied wall transpiration techniques to actively control the transient kinetic energy growth of the perturbations by the help of an LQR (Linear Quadratic Controller) controller. We solve the stability equation in the cylindrical coordinate system. The state-space model2 is formed for open loop (without control) and closed loop (with control) system. Further, variational method is used to optimize the growth of perturbation kinetic energy. A reduction of upto 72% is observed by application of the presented control technique.
About the Speaker
Prof. Vinod Narayanan is an Associate Professor in the Department of Mechanical Engineering at Indian Institute of Technology (IIT) Gandhinagar, India. He received Bachelor’s and Masters degree in Mechanical Engineering from University of Kerala, India. He completed his PhD from JNCASR Bangalore India.
His research interests are in hydrodynamic stability, transition, flow control. He also work in high speed flows with focus on scramjet engines and air-fuel mixing at supersonic speeds. Recently he started working isotopic decaying turbulence with colloidal suspensions.
Host: Professor Leonardo Chamorro