High temperature instantaneous supersonic flow measurement using hydroxyl tagging velocimetry

A miniature high-temperature supersonic flow simulation device has been introduced. The velocity distribution of the flow produced by the device was diagnosed using hydroxyl tagging velocimetry(HTV). Through changing the spatial position of the 193 nm laser relative to the flow, some HTV experimental images were acquired at different areas of the flow. And axial velocity distributions of the flow were calculated from the images. The measurement results indicated that the velocity of the flow in the compression area is much slower than that in the expansion area. In the initial part of the compression area the velocity at the flow center is higher than that at both sides, while in the second expansion area the velocity at the center is slower.