• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.100-106
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• 2020

Turbopumps for liquid rocket engines are exposed to various cavitation instabilities under their operating conditions. The instabilities affect the stability of the turbopumps. To make sure of the stability of the turbopump of KSLV-II, the present work examined the characteristics of the cavitation instabilities during the turbopump assembly test. In the test, the LOx pump was operated under super-synchronous rotating cavitation and attached to uneven cavitation. In the vibration analysis of the fuel pump, the characteristic frequency by the super-synchronous cavitation of the LOx pump was clearly shown.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.6
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• pp.93-100
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• 2020

The turbopump of the liquid rocket engine adapts an inducer to minimize the cavitation due to the variations of the propellants supply condition. However, the inducer introduces cavitation instabilities which are well-known problems in the engine development. In this paper, operational characteristics by the cavitation instabilities are analyzed and the reliability of the engine is checked when the first stage engine of the KSLV-II is tested at the low inlet pressure conditions. The characteristic frequencies representing the cavitation instabilities of the LOx pump are clearly found in various high frequency sensor signals around the entire engine in addition to the LOx and fuel pump.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2434-2439
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• 2008

This paper was studied on the cavitation instability of a Solution Pump Inducer in an absorption chiller-heater. Inlet pressure of LiBr and rotational speed at nominal mode are 2,800 Pa and 3,500 rpm respectively. Due to the marginal operation of available NPSH, the cavitation performance of the inducer is critical for the stable operation without the deterioration of head performance. In the study, cavitation performance and its mode of instability was investigated experimentally. Water was used as the working fluid and the test inducer was scaled up as 1.75 times for detail measurements and flow visualization. Inlet pressure was controlled by a vacuum pump. This research focused on types of cavitation instability and phenomena to investigate the possibility of harmful damage due to cavitation instability. Casing wall pressure and instantaneous inlet pressure was measured to observe the unsteady flow characteristics. Through the visualization and spectrum analysis of pressure, the occurrence region and intensity of asymmetric cavitation and cavitation surge are analyzed in the test inducer.