• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.275-278
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• 2010

By changing the nozzle throat area during the operation, thrust of a pintle thruster can be adjusted easily such as a liquid propulsion. In this paper, numerical analysis was carried out for SNECMA's pintle thruster with different pintle shapes. Flow field and aerodynamic load changed drastically with pintle shapes. Bore in the pintle decreased aerodynamic load significantly.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.17-23
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• 1998

A simplified experiment was performed to figure out the atomization characteristics of highly viscous liquid of rice-bran oil by applying ultrasonic energy to improve the atomization of spray droplets. A spray system, an ultrasonic system, and three kinds of pintle-type nozzles(pin-edge angle: 5 , 10 , 15 ) were manufactured. To investigate the effects of ultrasonic energy on the atomization of a highly viscous liquid, a phase doppler particle analyzer was used for the measurement and calculation of spray droplets data. Nozzle opening pressures were chosen of 3 levels, i.e, 10, 13, 16 MPa. As a result, it could be concluded that the ultrasonic energy was effective to improve the spray atomization when applied to the fuel by means of 3 different nozzles because of the effects of the liquid fuel cavitation and relaxation between molecules caused by ultrasonic energy. The improvement rate of the spray atomization by the ultrasonic spray atomization by the ultrasonic spray compared with the conventional spray was about 10% increase in the case of pintle type nozzles. With the increase of pin-edge angles the distribution lines by nozzle opening pressures are declined for both conventional and ultrasonic sprays. This means that the increase of the pin-edge angle improves the atomization of sprays.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.9
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• pp.1198-1206
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• 1997

The flow characteristics of an intermittent fuel injection into a stationary ambient air were investigated using gasoline. The measurements were made by two-channel, air cooling type Phase Doppler Anemometer(PDA) system (DANTEC, 750 MW). And a pintle type injector of MPI (Multi-point Port Injection) system was utilized as a fuel injector. The PDA receiver optic was set up in a 60.deg. C forward scatter arrangement to obtain the optimum scattering signal of fuel droplets. The data were obtained by synchronizing PDA system with the fuel injection period, and the axial and radial velocity and turbulent components of fuel droplets were mainly measured for the analysis of temporal and spatial distribution depending upon the fuel injection pressures.