Accession Number : ADA298555
Title : Diagnostic Developments for Velocity and Temperature Measurements in Uni-Element Rocket Environments
Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
Personal Author(s) : Philippart, Kenneth D.
PDF Url : ADA298555
Report Date : AUG 1995
Pagination or Media Count : 130
Abstract : Velocity and temperature measurements were taken within a uni-element rocket combustion chamber for hydrogen-oxygen propellants using laser Doppler velocimetry, thermocouples, and a thermocouple-based temperature rake developed for this effort. Velocity and turbulence profiles were obtained for firings with a gaseous oxygen (GO2)/gaseous hydrogen (GH2) coaxial shear injector at axial locations of 1.6 mm (0.063 in.), 6.4 mm (0.25 in.), 12.7 mm (0.5 in.), 25.4 mm (1 in.) and 50.8 mm (2 in.). Aluminum oxide particles of various sizes seeded the flow in an attempt to explain the discrepancies. While cold-flow simulations were promising, hot-fire results for the various particles were virtually identical and still lower than earlier data. The hot-firings were self-consistent and question the reproducibility of the previous data. Velocity measurements were made closer to the injector than the preceding work. Asymmetries were noted in all profiles. The shear layer displayed high turbulence levels. The central flow near the injector resembled turbulent pipe flow. Recirculation zones existed at the chamber walls and became smaller as the flow evolved downstream. The combusting flow region expanded with increasing axial distance. A thermocouple-instrumented coaxial injector was fired with GO2/GH2 propellants. The injector exit plane boundary conditions were determined. The feasibility of a thermocouple-based temperature rake was established. Tests at three axial positions for air/GM2 firings revealed asymmetric profiles. Temperatures increased with increasing axial distance.
Descriptors : *LASER VELOCIMETERS, *GASEOUS ROCKET PROPELLANTS, VELOCITY, HIGH TEMPERATURE, SIGNAL TO NOISE RATIO, AIR FLOW, THESES, TURBULENCE, TURBULENT FLOW, COMPUTATIONAL FLUID DYNAMICS, FLOW VISUALIZATION, PRESSURE MEASUREMENT, NITROGEN, HYDROGEN, OXYGEN, MASS FLOW, FLOW FIELDS, TEMPERATURE GRADIENTS, ALUMINUM OXIDES, DATA ACQUISITION, COMBUSTION CHAMBERS, FLAME PROPAGATION, INJECTORS, ROCKET ENGINES, THERMOCOUPLES, RAMAN SPECTRA, GAS SURFACE INTERACTIONS, DOWNSTREAM FLOW, SHEAR FLOW, RECIRCULATION, PIPE FLOW, COLD FLOW.
Subject Categories : Fluid Mechanics
Liquid Rocket Propellants
Combustion and Ignition
Distribution Statement : APPROVED FOR PUBLIC RELEASE