Abstract
Velocity measurements in gaseous flows such as micro flows, high-speed flows, and rarefied gas flows are very challenging because a PIV (particle image velocimetry) technique encounters a difficulty associated with patticle inertia. MTV (molecular tagging velocimetly) is one of the advanced techniques possible to measure the velocities in such gaseous flows. In this paper, we first introduce the MTV techniques applicable to gaseous flows. Secondly, acetone-based MTV is applied to supersonic microjets issuing from the two-dimensional Laval nozzle whose heights at the throat and exit are 286μm and 500μm respectively, and we discuss the statistical uncertainties in measured velocities. Finally, we describe the future prospects of MTV as a diagnostic tool of gaseous flows.
