Control of Base Flows with Micro Jets
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Maughal Ahmed Ali Baig
Abstract
This paper presents the results of an experimental investigation carried out to control the base pressure in a suddenly expanded axi-symmetric passage. Active control in the form of micro jets was employed to control the base pressure. Air injection at four locations at the base, symmetric to the nozzle axis was used as the active control. The jet Mach numbers at the entry to the suddenly expanded duct studied were 1.87, 2.2 and 2.58. The area ratio of the present study was 2.56. The length-to-diameter ratio of the suddenly expanded duct varied from 10 to 1. Nozzles generating the above jet Mach numbers were operated with nozzle pressure ratio (NPR) in the range 3 to 11. In addition to base pressure, wall pressure field along the duct was also studied. It is found that the active control in the form of blowing through small orifices (micro jets) are effective in controlling the base pressure field. As high as 65 percent increase in base pressure was achieved for certain combination of parameters of the present study. Micro jets do not disturb the flow field in the enlarged duct.
Copyright © 2011 De Gruyter
Articles in the same Issue
- Future Jet Technologies. Part A. Air, Land and Marine Applications of Thrust Vectoring
- Aerodynamic Characteristics of Three-Dimensional Surface-Mounted Objects in Tandem Arrangement
- GUI Type Fault Diagnostic Program for a Turboshaft Engine Using Fuzzy and Neural Networks
- Numerical Modeling of an Axisymmetric Trapped Vortex Combustor
- Optimization of a Francis Turbine Through Flow Simulation with a RNG k-ω Turbulence Model
- Control of Base Flows with Micro Jets
- Analysis on Cavitation Characteristics of Flow in a Francis Turbine with Different Content of Non-Condensable Gas
- Research on the Optimum Clocking Position in Axial-Flow Turbomachinery
- Asymmetrical Flow Simulation of Icing Effects in S-Duct Inlets at Angle of Attack
- Experimental Investigation of a Twin Fluid Atomizer Spray Using a Diode Laser Based Optical Patternator
Articles in the same Issue
- Future Jet Technologies. Part A. Air, Land and Marine Applications of Thrust Vectoring
- Aerodynamic Characteristics of Three-Dimensional Surface-Mounted Objects in Tandem Arrangement
- GUI Type Fault Diagnostic Program for a Turboshaft Engine Using Fuzzy and Neural Networks
- Numerical Modeling of an Axisymmetric Trapped Vortex Combustor
- Optimization of a Francis Turbine Through Flow Simulation with a RNG k-ω Turbulence Model
- Control of Base Flows with Micro Jets
- Analysis on Cavitation Characteristics of Flow in a Francis Turbine with Different Content of Non-Condensable Gas
- Research on the Optimum Clocking Position in Axial-Flow Turbomachinery
- Asymmetrical Flow Simulation of Icing Effects in S-Duct Inlets at Angle of Attack
- Experimental Investigation of a Twin Fluid Atomizer Spray Using a Diode Laser Based Optical Patternator
