4 papers
Linear and Nonlinear Disturbance Evolution on the Frustum of Hypersonic Ogive-Cylinders
Hemanth Goparaju, Kunal Kanawade, S Unnikrishnan +1
Aspects of transition mechanisms on a sharp-nosed ogive-cylinder at Mach~ are elucidated by considering linear and nonlinear disturbance evolution of freestream sto…
Instabilities and transition in cooled-wall hypersonic boundary layers
S. Unnikrishnan, Datta V. Gaitonde
Wall cooling has substantial effects on the development of instabilities and transition processes in hypersonic boundary layers (HBLs). A sequence of linear stability theory, two-d…
Linear, nonlinear and transitional regimes of second mode instability
S. Unnikrishnan, Datta V. Gaitonde
The 2D second-mode is a potent instability in hypersonic boundary layers (HBLs). We study its linear and nonlinear evolution, followed by its role in transition and eventual breakd…
A Robust Approach for Stability Analysis of Complex Flows Using Navier-Stokes Solvers
Rajesh Ranjan, S. Unnikrishnan, Datta Gaitonde
Direct methods to obtain global stability modes are restricted by the daunting sizes and complexity of Jacobians encountered in general three-dimensional flows. Jacobian-free itera…