Supercritical nitrogen free jet investigated by spontaneous Raman scattering
- Cite this article as:
- Oschwald, M. & Schik, A. Experiments in Fluids (1999) 27: 497. doi:10.1007/s003480050374
The injection of fuel and oxidizer in high pressure rocket combustion chambers is simulated in a model experiment dedicated to investigate the phenomenology of coaxial injection at supercritical pressures. Cryogenic nitrogen is injected in a pressurized reservoir of N2 at ambient temperature at 4 Mpa and 6 Mpa, above the critical pressure for nitrogen of 3.4 Mpa. The radial density distribution of the N2 is determined by spontaneous Raman-scattering, from the measured densities temperature distributions are derived. The radial density and temperature pro les are analyzed as a function of the distance from the injector for x/D = 1 to 30. The influence of density gradients, internal field effects and interference effects on the performance of the Raman technique when applied to turbulent high density flows is discussed.