Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 10 of 10 for “"Helium Injection"”.
-
Experimental investigation of helium injection at a low downstream angle into supersonic flow
Experiments were performed with single, sonic, helium jets at downstream angles of 15° and 30° relative to the free stream to determine their mixing, penetration and total pressure loss when injected into a supersonic air cross flow. From this information, the performance of these jets as fuel …
-
Effect of helium injection on diffusion dominated air ingress accidents in pebble bed reactors
… diffusion phase, by injecting minute amounts of helium into the top of the reactor to set up a counter helium-air diffusion circuit. By delaying the onset of natural circulation, air enters the reactor only at diffusion transport rates, instead of much higher natural convection transport rates. …
-
Experimental and computational investigation of helium injection into air at supersonic and hypersonic speeds
Experiments were performed with two different helium injector models at different injector transverse and yaw angles in order to determine the mixing rate and core penetration of the injectant and the flow field total pressure losses. when gaseous injection occurs into a supersonic freestream. …
-
Fuel-vortex interactions for enhanced mixing in supersonic flow
… a Reynolds number of 3.63 x 10⁷ per meter and helium injection with jet-to-freestream momentum flux ratios of 1.0 and 2.0. Planar-laser Rayleigh scattering and conventional probing techniques including species composition sampling were employed to interrogate the flow field at several …
-
Sound produced by entropic and compositional inhomogeneities
… of the sound field resulting from air injection and extraction, heat addition and helium injection. For the first time, direct, entropic and compositional noise are clearly identified in the experimental data, and shown to be in line with theoretical predictions. The results provide the …
-
Experimental investigation of normal, sonic injection through a wedge-shaped nozzle into supersonic flow
An experimental evaluation of normal, sonic, helium injection from a wedgeshaped nozzle and a circular nozzle into a Mach 3 free stream with a total pressure of 6.5 atm and a total temperature of 294 K was conducted. The expansion ratio and the mass rate of flow of both nozzles were matched in …
-
Mean-flow measurements of a turbulent mixing layer from helium slot injection into a supersonic airstream
… the mixing in a shear layer developed from helium slot injection into a parallel supersonic airstream and compares the results to those of previous slot-injection tests. The objectives of this study include documenting the helium slot-injection flowfield; providing a baseline for use as a …
-
A mach 1.95 free-jet facility for experimental investigation of injectant flow patterns
… were evaluated in the facility. Normal, sonic injection of helium through a circular injector was studied as a way to evaluate nanoshadowgraph photography, oil flow photography, and infrared imaging as qualitative flow visualization methods. Quantitative measurements of the local helium …
-
Oscillating shock impingement on low-angle gas injection into a supersonic flow
… on a 15° downstream angled, underexpanded, sonic helium jet injected into a supersonic airflow. Information on mixing, penetration, total pressure loss and turbulence structure from these experiments was used to estimate mixing control achieved by adding an oscillating shock to the helium …
-
Experimental Investigation of a Flush-Walled, Diamond-Shaped Fuel Injector for High Mach Number Scramjets
… from the wall. Test conditions involved sonic injection of helium heated to approximately 313 K into a nominal Mach 4.0 crossstream airflow. These conditions are typical of a scramjet engine for a Mach 10 flight, and heated helium was used to safely simulate hydrogen fuel. The injector was …