On three-dimensional boundary layer stability analysis on curved aerodynamic surfaces

Abstract

Numerical simulation of three-dimensional flow past a prolate spheroid located at an angle of attack of 10° accompanied by the laminar-turbulent transition was performed for subsonic (M∞ = 0.136) and transonic (M∞ = 0.75) velocities. The general-purpose gas-dynamic package ANSYS Fluent in integration with a laminar-turbulent transition module based on software bundle LOTRAN 3 was used. The principles of numerical simulation of the main flow are discussed: requirements for the near-wall region allocation and independence of the results from various methods of presetting the position of forced turbulence. It was shown that two instability mechanisms take place in the boundary layer of the spheroid: the Tollmien-Schlichting instability and the cross-flow instability with a predominance of the last on side surfaces. A comparison of predicted position of the transition for different flow regimes was performed.