Turbulent Transition Over Conical Nose Cones Combining Yaw and Nose Bluntness Effects
Abstract
We propose combined numerical simulations and experiments on a conical nose geometry with variable nose bluntness and at yaw angles that focus on the combined mechanisms of 2nd Mode and cross-flow instabilities leading to transition to turbulence. The two mechanisms of turbulence transition are usually considered in isolation, with the delimiter usually being the degree of yaw angle. However little is known for intermediate yaw angles where both mechanisms are viable routes to transitions, and in which potential interaction between the two instabilities might occur that impacts transition predictions based on a linear theory eN method. At hypersonic Mach numbers, turbulence transition has a critical impact on surface heat flux. This motivates techniques for transition control. 2nd mode ampli fication can be reduced through increased nose bluntness. Turbulent transition resulting from cross-flow instability can be suppressed with specifi cally tailored discrete roughness. Both approaches are based on linear theory predictions of each mechanism in isolation. The proposed research will investigate conditions at which both instability mechanisms exist simultaneously. It will investigate the potential for interactions, and provide a framework for transition prediction in this instance. Based on this understanding, it will develop mechanistic approaches to transition control. The practical impact is on reducing the thermal requirements on materials, apertures and sensors located on the aft portion of hypersonic vehicle nose cones.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 21, 2021
- Source ID
- N001742110007
Entities
People
- Eric Matlis
Organizations
- United States Navy
- University of Notre Dame