Shear flow control of gas jets in liquids
Abstract
Passive control of shear flow is used to control the rate of mixing and stability of submerged gaseous jets in liquids. The object is to evaluate the effectiveness of recently developed shear flow control techniques for application to gaseous jets injected into liquids and ultimately to apply these techniques to gaseous oxidants injected into liquid metal fuels. These control techniques have been initially tested in nonreacting gas/liquid systems. A large increase in the degree of mixing and jet stability occurs when non-axisymmetric nozzles are used as injectors relative to injection by axisymmetric Fanno tube type nozzles. Jet volume spreading rate is increased by a factor of 4. A characteristic instability (the 'reverse shock' or reverse flow effect) occurring in such two-phase systems is greatly reduced by passive control of the shear flow. A simple passive technique of controlling entrainment is described which is effective in eliminating the reverse flow effect. The relevance of these control techniques to liquid metal combustion is discussed.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- March 1993
- Bibcode:
- 1993STIN...9411448O
- Keywords:
-
- Combustion Control;
- Control Systems Design;
- Entrainment;
- Fuel Injection;
- Gas Jets;
- Liquid Metals;
- Metal Combustion;
- Metal Fuels;
- Metal Propellants;
- Shear Flow;
- Flow Visualization;
- Jet Mixing Flow;
- Nozzle Flow;
- Oxidizers;
- Secondary Flow;
- Underwater Vehicles;
- Fluid Mechanics and Heat Transfer