Rayleigh Scattering Studies of CO2 Expansion Flow Fields.

Sonic orifice expansions of CO2 were investigated using laser Rayleigh scattering for detection of condensation onset within the expansion flow field. The axial region studied was 0.8 to 60 orifice diameters downstream of the orifice, and a range of reservoir pressures was employed for expansions of CO2 at ambient temperature. Two sonic orifice sources, 1.325- and 3.2-mm diameter, were studied for the purpose of determining the appropriate reservoir scaling laws for condensation onset and growth. Rayleigh scattering intensities are presented as a function of axial distance and reservoir pressure, and the results clearly show the regions of condensation onset and growth.
Prepared in cooperation with ARO, Inc., Tullahoma, Tenn. Rept. no. ARO-VKF-TR-75-104.