Comparison of electron and electronic temperatures in recombining nozzle flow of ionized nitrogen–hydrogen mixture. Part 2. Experiment

Abstract

This is part 2 of a two-part paper. In this part, visible and infrared line radiations from nitrogen and hydrogen are measured with a spectrograph in an ionized flow expanding through a supersonic nozzle, wherein the hydrogen content is less than 0·1 %. The geometry and stagnation conditions are those for which the calculations were made in part 1. The experiment confirms quantitatively the predictions of part 1 that the electronic excitation temperatures of hydrogen aud (3P) core states of nitrogen are higher than the electron temperature, and that (3P) excitation temperatures exhibit maxima within the nozzle. The measured excitation temperatures of states with (1D) core are found to agree with the calculated electron temperatures.