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.