Library Subscription: Guest
TSFP DL Home Archives Executive Committee

QUANTITATIVE MEASUREMENTS OF ABLATION-PRODUCTS TRANSPORT IN A SUPERSONIC TURBULENT BOUNDARY LAYER USING SIMULTANEOUS PIV AND NAPHTHALENE PLIF

Christopher S. Combs
Department of Aerospace Engineering and Engineering Mechanics The University of Texas at Austin 210 E. 24th St., Austin, Texas, 78712, United States

Noel T. Clemens
Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, 210 East 24th Street, Austin, TX 78712

Abstract

The dispersion of a passive scalar in a Mach 5 turbulent boundary layer is investigated using a lowtemperature sublimating ablator (naphthalene). Twodimensional fields of naphthalene mole fraction and velocity are obtained by using simultaneous particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF). The images show large-scale naphthalene vapor structures that coincide with regions of relatively low streamwise velocity. Additionally, the covariance of naphthalene mole fraction with velocity indicates that an ejection mechanism is transporting low-momentum, highscalar-concentration fluid away from the wall, resulting in the protrusions of naphthalene vapor evident in the instantaneous PLIF images. Mean profiles of streamwise velocity and naphthalene mole fraction are also presented, with the mean mole fraction profile having the expected shape of a classical scalar boundary layer profile.