• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.2
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• pp.37-44
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• 2002

A theoretical study of spray and combustion characteristics due to coaxial twin-fluid injection is conducted to investigate the effects of liquid jet property, droplet size, contact length and liquid jet velocity. Model is properly validated with measurements and shows good agreement. Prediction of jet contact length, droplet size, liquid jet velocity reflects genuine features of coaxial injection in physical and practical aspects. Both the jet contact length and tile droplet size are reduced in a linear manner with an increase of injector diameter. Cross sectional area of liquid intact core is reduced with augmented jet splitting rate, thus the jet is accelerated to maintain the mass continuity and with an assistant of momentum diffusion by burnt gas.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.6
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• pp.78-84
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• 2020

The performance of pintle thruster is analyzed by using the pintle thruster performance analysis model which integrating the element models introduced in Part I. To verify the performance analysis, the results of the developed program are compared with the experimental data of kerosene/hydrogen peroxide liquid pintle thrusters. Based on the results, the characteristics of the pintle thruster are analyzed. The sensitivity analysis is performed to investigate the effect of thruster shape and operation parameters on performance characteristics using both OAT and scatter plot methods. The four performance parameters such as droplet diameter, film flow rate, O/F ratio, and nozzle throat diameter are evaluated to investigate their effects on characteristic speed, combustor pressure, and specific thrust.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1079-1089
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• 2013

The flow characteristics in a solid particle incinerator are investigated numerically for high burning rate of wastes. The studied incinerator employs both a swirl flow used in the furnace of powerplants and a design concept applied to a rocket combustor. As the first step, the non-reactive flow field is analyzed in the incinerator with primary and secondary injectors through which solid fuel and air are injected. The deflection angle of a primary injector, inclination angle of a secondary injector, and gap between the two types of injectors are selected as design parameters. The swirl number is adopted for evaluating the degree of swirl flow and estimated over wide ranges of three parameters. The swirl number increases with deflection angle, but it is affected little by inclination angle. Recirculation zones are formed near the injectors, and their size affects the swirl number. The swirl number decreases with the zonal size of recirculation. From the numerical results, the design points can be found with strong swirl flow.