• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.311-312
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• 2006

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.87-92
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• 2021

In this study, a numerical approach was utilized to observe the phenomena in the ground combustion test of a gas generator for a ducted rocket with a plunger-type flow control device. The design factors were also identified through the analysis. It was observed that the pressure increase without the adhesion of the combustion product at the discharge pipe was quite similar to the analysis assuming a cone-shaped erosive burning effect. The pressure increase in most cases was similar to the analysis results when assuming the change in discharge pipe area due to the adhesion of combustion products. Moreover, it was also established that for a given grain shape and discharge flow area, the effect of the adhesion of combustion products has a significant effect on the combustion chamber pressure for cases over n=0.45.

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.79-86
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• 2021

For a preliminary study on a thrust-throttleable Variable Flow Ducted Rocket, a gas generator and flow control valve were developed, and ground combustion tests were performed. The gas generator and flow control valve operated at the required performance level for parameters, such as heat-resistance, combustion-time, pressure, and temperature. The combustion characteristics of a fuel-rich solid propellant mixed with Boron/MgAl/AP, etc., were also analyzed. A Plunger-type flow control valve was designed to control the discharge flow area, and it was confirmed that the flow control valve was able to control the combustion gas flow rate and pressure. However, due to the reduction of the discharge flow area caused by adhesion of combustion products, the combustion pressure continuously increased. The analysis of the pressure increase is covered in Part 2 of this paper.