Rotational Accommodation of NO on a Hot SiC-Surface in a Rarefied Flow

Laser-induced fluorescence (LIF) spectra of NO seeded in He have been measured in a rarefied hypersonic free jet flow. A SiC-disk (heat protection material used for reentry bodies) was installed in the V2G (Vacuum Wind Tunnel Goettingen). NO molecules, reflected from the heated surface, were excited within the D(0)-X(1)-band. From the fluorescence, rotational temperatures could be determined; the reflected molecules are not completely accommodated to the wall temperature of the hot disk model