Effects of Mass Transfer on Transition Behavior at High Speeds,

Abstract

Surface heat transfer and boundary layer transition easurements have been performed on a slender blunted cone at = 8.0. These measurements have been obtained on the conical surface with mass transfer occurring on the spherical nose cap. The free stream Reynolas number, based on nose radius, varied between .6,cl and i s-. Data was obtained both at zero angle of at-*tack and at angles as high as WX, which exceeds the semi-vertex. cone angle of "We. The technique utilized in the determination. of transition location was the observation of the RKS output of a thih film gauge, imbedded in the model surface, and maintained at a constant temperature by an anemoeter system. A sudden change in the RMS output of the film gauge r' s found to accurately locate the onset of boundary layer transition.

Hypersonic Boundary-Layer Transition with Ablation and Blowing

“…The present author is skeptical about the streamwise relaminarization that is inferred by comparing heat transfer to the film-cooling boundary layer code. It appears that similar skepticism existed at the time, for hotfilm measurements were later performed in the same facility to clarify this issue [42]. In combination with the work of Martellucci and others, these measurements might shed light on the effect of nosetip ablation on frustum transition.…”

“…However, p. 9 of Ref. [42] states thats is the distance from the stagnation point divided by the nose radius. Starkenberg's Ph.D. thesis probably provides additional information.…”

“…Plostins and Cresci carried on the work of Starkenberg and Cresci [41] by measuring with a single flush-mounted hot-film in the same tunnel [42]. Freestream unit Reynolds numbers varied from 0.14 to 1.6 million per foot, at a total temperature of 2000 • R. Plostins fabricated a 10-deg.…”