Internal structure of LSD wave based on a 1-D laser‑induced discharge model: Comparison between numerical simulation and experiment

Repetitively pulsed (RP) laser propulsion is one of the key beamed energy propulsion (BEP) technological concepts for future space missions. The mechanism by which a laser beam source is absorbed to produce plasma in an ambient gas and to propagate an ionization wave efficiently for thrust generation is termed as laser supported detonation (LSD). Discharge-based physics is required to describe the LSD wave propagation properties as detonation theory based only on hydrodynamic relations is inadequate to do. This paper describes a computational fluid dynamics (CFD) simulation tool for laser-produced plasma fluid system based on a 1-D photoionization-induced laser discharge model. The set of equations described here consists of radiative transfer equations coupled with plasma fluid equations. The simulated results for argon gas at 1 atm, based on the model, are compared with experimentally observed results for the same gas in order to validate the model. The simulated results are shown to be consistent with experimentally obtained characteristics of the internal structure of the LSD wave.