• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.523-526
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• 2006

A series of hydraulic and cavitation tests are performed in water environment in order to verify the hydraulic and cavitation performance of three types of LOX pumps. All the performances of the pumps are found to be satisfied with each design requirement. In the hydraulic tests, the head and efficiency are increased as the gap between floating ring seals and the impeller shoulder is decreased. In the cavitation tests, some pumps show decrease in the cavitation performance as the flowrate of the pump is decreased.

• Korean Journal of Pharmacognosy
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• v.19 no.3
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• pp.174-176
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• 1988

From the stem barks of Tilia mandsurica, fraxin ( I ) and 1, 10-decanedicarboxylate ( II ) were isolated and characterized by spectral data. 1, 10-decanedicarboxylate was the first isolation from Tilia plants.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.348-353
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• 2005

A cryogenic test facility has been developed to perform inducer and pump tests using liquid nitrogen. Performance tests of a turbopump in the maximum 50ton-thrust class can be performed with cryogenic fluid in the facility which operates at a temperature around $-196^{\circ}C$ with the rotational speed up to 30,000rpm. To verify the reliability of the cryogenic pump test facility, hydraulic performance tests of an inducer were accomplished, and their results were compared with the result from a water test The results confirm the reliability of the cryogenic test facility, and it is expected to contribute for on-going development of a turbopump for liquid rocket engines.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.650-654
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• 2005

Computational and experimental studies on the forward-sweep inducer for the rocket-engine turbopump are presented in comparison with the conventional backward-sweep inducer. It is shown that back flows at the inlet decreases for forward-sweep inducers. And the low pressure region at the back flow are also decreased, which is assumed to promote the suction performance of the inducers. The backward-sweep inducer shows almost the same suction performance as that of the backward-sweep inducers although it has small inlet tip diameter and shorter length. And the efficiency of the forward-type inducer shows better results than the backward-sweep inducer due to the small size of backflows.

• Aerospace Engineering and Technology
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• v.10 no.1
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• pp.122-128
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• 2011

A series of water tests of a Lox pump for liquid rocket engines are performed at a room temperature. According to the hydraulic test results, the head coefficient is slightly decreased when the rotational speed of the pump is increased. However the efficiency is high at the high-speed test. Also, according to the cavitation test results, the cavitation performance of the pump is found to be decreased when the flow ratio is less than 92%. Furthermore, the vibration characteristic is analyzed using measured high frequency data.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.558-563
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• 2004

Experiments were performed to see the effect of radial tip clearance on a turbopump inducer, which has two blades with inlet tip blade angle of 7.8 degree and tip solidity of 2.7. Hydraulic and cavitation tests were done for three cases of tip clearance ratio, that is, 0.026, 0.053, and 0.079. With increase in the tip clearance, inducer head and pressure on the inducer tip decreased. Attached cavitation and cavitation surge were found in the cavitation tests. In the attached cavitation one cell rotated at the same rotational speed as that of the inducer. Cavitation performance deteriorated with increase in the tip clearance. The level of casing vibration increased in the cavitation condition and the level was very high when the attached cavitation appeared.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.147-147
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• 2005

• The KSFM Journal of Fluid Machinery
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• v.9 no.4 s.37
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• pp.20-26
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• 2006

A cryogenic test facility has been developed to perform inducer and pump tests using liquid nitrogen. Performance tests of a turbopump in the maximum 50ton-thrust class can be performed with cryogenic fluid in the facility which operates at a temperature around -196oC with the rotational speed up to 30,000rpm To verify the reliability of the cryogenic pump test facility, hydraulic performance tests of an inducer were accomplished, and their results were compared with the result from a water test. The results confirm the reliability of the cryogenic test facility, and it is expected to contribute for on-going development of a turbopump for liquid rocket engines.

• The KSFM Journal of Fluid Machinery
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• v.9 no.1 s.34
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• pp.19-24
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• 2006

Experiments are carried out to investigate the effect of radial tip clearance on a turbopump inducer, which has two blades with inlet tip blade angle of 7.8 degree and tip solidity of 2.7. Hydraulic and cavitation tests are performed for three cases of tip clearance ratio, that is, 0.026, 0.053, and 0.079. With increase in the tip clearance, inducer head and pressure on the inducer tip decrease. Attached cavitation and cavitation surge are observed in the cavitation tests. In the attached cavitation one cell rotates at the same rotational speed as that of the inducer. Cavitation performance deteriorates with increase in the tip clearance. The level of casing vibration increases in the cavitation condition and the level is very high when the attached cavitation appears.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.240-244
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• 2004

Characteristics of steady and unsteady cavitation in a turbopump inducer were investigated in this paper. To see the effect of tip clearance on the inducer performance, three cases of tip clearance were tested. The helical inducer, which has two blades with inlet tip blade angle of 7.8 degree and tip solidity of 2.7, was tested in the water. In the non-cavitating condition, the inducer head decreased with increase in the tip clearance. Rotating cavitation and cavitation surge were observed through unsteady pressure measurements at the inducer inlet. The cell number and propagation speed of the rotating cavitation were determined through cross-correlation analysis. During the rotating cavitation one cell rotated at the same rotational speed as that of the inducer rotation and the cavitation surge did not rotate. The critical cavitation number increased with increase in the tip clearance at the same flow rate, but the change of critical cavitation number was small at the nominal flow rate.