Modeling Laser Absorption Measurements in a Shock Tube using the Photon Monte Carlo Method

The photon monte carlo (PMC) method has been used to model laser absorption measurements in a shock tube by solving the radiative transport equation for a one-dimensional computational domain. A new wavelength selection procedure has been implemented to select wavelengths for photon bundles at initialization which has been shown to be significantly faster than other various root-finding algorithms. The PMC method was applied to simulate tunable diode laser absorption spectroscopy (TDLAS) measurements targeting nitric oxide (NO) ro-vibrational transitions in the infrared (IR) region behind a normal air shock for different laser beam powers.