Turbulent Mixing in Inert and Combusting Flows Visualized by HF Tracer Absorption

Abstract

A noninterfering diagnostic technique that employs monomeric hydrogen fluoride, HF, as a passive tracer gas has been developed. Infrared absorption by HF is used to infer turbulent mixing rates in inert and combusting flows. Data are presented on the turbulent diffusion of HF seeded streams of air, heated air, H₂, and CO₂ into an outer coaxial air stream. Combustion of C₂H₂ and air in a free jet configuration has also been investigated with the H F tracer. In most of these flow situations, the HF exhibited apparent rotational nonequilibrium. Development of the experimental technique and methods for data acquisition and analysis are discussed.