Hypersonic Laminar Boundary Layer Transition. Part 1. Nosetip Bluntness Effects on Cone Frustum Transition. Part 2. Mach 6 Experiments of Transition on a Cone at Angle of Attack
Abstract
The effects of nosetip bluntness on cone frustrum boundary layer transition were investigated by conducting hypersonic wind tunnel experiments. Frustrum transition Reynolds numbers were found to have large variations within the entropy layer swallowing region. Investigation results indicated that several nosetip blunting effects were competing for the dominant role in the frustrum transition process and it was speculated that the large variations in transition Reynolds number were associated with the shifting of dominant roles. Based upon these studies, dominant nosetip bluntness effects are tentatively identified with three regions of the entropy layer. Transition movement and patterns on the frustrum of a cone at small angles of attack were investigated at a Mach number of 5.9, using an 8-deg half angle cone with both sharp and blunt nosetips. Small angles of attack produced large asymmetries in the frustrum transition pattern for both sharp and blunt tipped configurations. For the configurations with nosetip bluntness most of the frustrum transition asymmetry occurred between meridian angles of 60 and 120 deg. Data obtained with simulated laminar ablated nosetips were generally representative of what would be expected with a larger spherically blunt nosetip. Keywords: Boundary layer transition; Angle of attack.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1986
- Accession Number
- ADA178877
Entities
People
- Kenneth F. Stetson
Organizations
- Wright Laboratory