• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.66-72
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• 2020

In this study, a method for increasing the initial water supply was employed to protect the water injection nozzle by the flame when supplying the water to the steam generator. During the initial steam generator test, the flow rate was controlled by using the only venturi, but cooling water was not supplied to the combustion chamber at the beginning of combustion, thereby resulting in damage to the water nozzle. To solve this problem, a venturi and an orifice were configured in parallel to increase the initial supply flow rate to form a differential pressure between the water manifold and the combustion chamber. Venturi and orifice supply sequences were established through the water flow tests, and combustion tests were conducted for final verification. Consequently, a continuous supply of the cooling water at the beginning of combustion was achieved, and the experiment was successfully performed without damaging the cooling water nozzle.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.26-32
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• 2020

In this study, a facility was constructed to supply liquid nitrogen to simulate combustion instability in a liquid rocket combustor. The pressurization and supply performances were predicted and verified through different experiments. The liquid nitrogen supply system was composed of a pressurized supply system, and a dome regulator was used to adjust the pressure of the pressurant. A cavitation venturi was used to control the mass flow rate of liquid nitrogen. The condition of liquid nitrogen supply was a mass flow rate of 2.55 kg/s and the venturi inlet pressure was above 100 bar. Based on the initial experiment, it was observed that the predicted amount of the pressurant was not sufficiently supplied and the target pressure was not supplied due to a drop in tank pressure. Through the modification of the established facilities, the target mass flow rate was successfully supplied and the cryogenic liquid nitrogen supply facility was verified.