Numerical simulation of active control of boundary layer transition
Abstract
A numerical model has been developed for investigating boundary layer transition control for a threedimensional flat plate boundary layer. Control of a periodically forced boundary layer in an incompressible fluid is studied using surface heating techniques. The spatially evolving boundary layer is simulated. The NavierStokes and energy equations are integrated using a fully implicit finite difference/spectral method. The NavierStokes equations are in vorticityvelocity form and are coupled with the energy equation through the viscosity dependence on temperature. Both passive and active methods of control by surface heating are investigated. In passive methods of control, wall heating is employed to alter the stability characteristics of the mean flow. Both uniform and nonuniform surface temperature distributions are studied. In the active control investigations, temperature perturbations are introduced locally along finite heater strips to directly attenuate the instability waves in the flow. A feedback control loop is employed in which a downstream sensor is used to monitor wall shear stress fluctuations. Passive control of small amplitude twodimensional TollmienSchlichting waves and threedimensional oblique waves are numerically simulated with both uniform and nonuniform passive heating applied.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 December 1988
 Bibcode:
 1988STIN...8922068K
 Keywords:

 Active Control;
 Boundary Layer Control;
 Boundary Layer Transition;
 Digital Simulation;
 Flat Plates;
 Flow Equations;
 NavierStokes Equation;
 Finite Difference Theory;
 Flow Distribution;
 Flow Stability;
 Incompressible Flow;
 Shear Stress;
 Surface Temperature;
 Three Dimensional Flow;
 Fluid Mechanics and Heat Transfer