• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.14-17
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• 2010

To identify the turbulent flow characteristics resulted from the swirl direction of a combustor with seven swirl injectors, a 3D Large Eddy Simulation(LES) was implemented. The combustor of concern is the LRE combustor, designed by Aerospace Combustion Laboratory of Georgia Institute of Technology. The seven-clockwise-swirl-injectors combustor produces stronger flow interference among injectors, specially obvious tangential velocity near the wall, than the combustor with four-clockwise and three-counterclockwise swirl injectors. In addition, pressure fluctuations in the combustor with seven-clockwise-swirl-injectors was more amplified.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.282-287
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• 2004

Unielement combustion tests were conducted using coaxial bi-swirl injectors. Major experimental parameters were a recess length and a fuel-side swirl chamber. Combustion efficiency mainly depends on a mixing mechanism for the present coaxial swirl injectors. Low-frequency pressure excitations around 200Hz were observed for all injectors. However, dynamic behaviors considerably differ for an external and an internal mixing case controlled by a recess length. The internal mixing induces mixture to be biased at a specific frequency in a mass flow rate, which results in a relatively high amplitude of pressure fluctuations but results for the external mixing case show that fuel and oxidizer mixture flow carries more complicated, multiple wave characteristics due to broad mixing region as well as disintegration and merging phenomena of propellant films.

• Journal of ILASS-Korea
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• v.23 no.4
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• pp.159-168
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• 2018

Thrust throttling in a liquid rocket engine can be implemented via several ways such as high pressure drop injector, dual manifold, multiple chamber, pintle injector, and gas injection. Thrust throttling using gas injection controls thrust by usually injecting inert gas into propellant through an aerator to reduce the propellant's bulk density. In this study, the outside-in aerator was used in the propellant line to create two phase flow. Closed-type, open-type, and screw-type bi-swirl coaxial injectors were utilized for investigating throttling characteristics such as pressure drop, mixture density, and discharge coefficient according to gas-liquid mass ratio.