SURFACE ABLATION PATTERNS - A PHENOMENOLOGY STUDY

This paper presents experimental observations concerning the formation of diamondshaped surface ablation patterns. These patterns have developed on several types of ablation materials (melting, subliming, and char forming) under diverse flow conditions. The pattern angle is shown to correlate with the local Mach angle for all classes of materials. A ratio of the pattern wavelength to the boundary-layer thickness appears to be insensitive to the dimensionless blowing rate or Mach number. The frequent appearance of longitudinal grooves upstream of the diamond patterns suggests a relation between longitudinal vorticity and pattern development. This study emphasizes the surface pattern phenomena on char forming materials. © 1969 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.