Experimental investigation on high-enthalpy sphere flow field using absorption spectroscopy

In this paper, we report an experimental study using tunable diode laser absorption spectroscopy (TDLAS) in high enthalpy sphere flow field. Based on the relatively strong direct absorption level of the oxygen atom ⁵P₃ ← ⁵S⁰₂ transition near the wavelength of 777.2 nm in a high-temperature environment, a flow-field component measurement system was set up to measure the flow field temperature and the component concentration in the region where the head of the sphere model. The analysis of the experimental data shows that the sphere flow field can achieve a high total temperature of more than 10000 K at the stationary point of the ball head model, and can be used to carry out the study of the components of the disturbed flow field and the total temperature study. This experiment has preliminarily verified the feasibility of using the oxygen atom TDLAS to evaluate the high enthalpy sphere flow field.