Measuring molecular flows with high-resolution stimulated Raman spectroscopy

We propose using high-resolution stimulated Raman spectroscopy to directly measure high-speed molecular flow velocities in wind tunnels and in combustive chambers. Our feasibility study indicates that flow speeds from Mach 0.04 up may be measured with the proposed method using available laser systems. It is pointed out that the success of the proposed technique will make possible the potential of measuring all interesting flow parameters, i.e., species concentration, temperature, and velocity, in a time of less than 1 μs at a repetition rate of 10⁴/s using a single experimental arrangement.