Measurement of highvelocity gas flow parameters using laser Brillouin scattering

Laser Brillouin scattering is the result of the inelastic light scattering from the medium density fluctuations. The shape of the Brillouin scattering spectrum is dependent on the gas pressure, temperature, and the scattering angle. An effective nonintrusive method for measuring the temperature and pressure in gas flow was provided. The measurement principle of the highvelocity gas flow parameters by using laser Brillouin scattering was reviewed. A measurement device based on the FabryPerot interferometer (FPI) was designed to measure the RayleighBrillouin spectrum of the gas flow, and the laser Brillouin scattering spectrum was obtained for a N2 gas flow. Experimental results show that the error of the pressure and temperature derived from the Brillouin scattering spectrum is less than 15% compared with the theory model.