Quantitative Heat Transfer Measurement Using Thermographic Phosphors

Abstract

A technique to obtain, optically, quantitative heat transfer distributions on wind tunnel models in short-run duration facilities is discussed. The phosphor coating is very sensitive to temperature and the activating ultraviolet radiation intensity but insensitive to aerodynamic surface loads and surface contamination. These characteristics, combined with millisecond response time, have made accurate thermal mapping practical under transient conditions. Visible and infrared radiation from the gas cap on blunt bodies has been effectively filtered without impairing the usefulness of the phosphor.