• The KSFM Journal of Fluid Machinery
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• v.8 no.3 s.30
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• pp.42-47
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• 2005

Effects of a booster inducer on the suction performance of turbopumps are investigated in this paper. To see the effect of the booster inducer, suction performance tests are conducted with and without the booster inducer for three turbopumps. It is shown that the booster inducer can enhance the suction performance of turbopumps when the tip clearance of the main inducers are relatively large. Numerical analysis are also carried out to see the effects of the booster inducer on the performance of the main inducer. The booster inducer is shown to increase the static pressure at the inlet of the main inducer and prevent growing of inlet back flows which are believed to have deleterious effects on the suction performance of the inducer.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.552-557
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• 2004

Effects of a booster inducer on the suction performance of turbopumps are investigated in this paper. To see the effect of the booster inducer, suction performance tests are conducted with and without the booster inducer for three turbopumps. It is shown that the booster inducer can enhance the suction performance of turbopumps when the tip clearance of the main inducers are relatively large. Numerical analysis are also carried out to see the effects of the booster inducer on the performance of the main inducer. The booster inducer is shown to increase the static pressure at the inlet of the main inducer and prevent growing of inlet back flows which are believed to have deleterious effects on the suction performance of the inducer.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.4
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• pp.382-388
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• 2004

The hydraulic and suction performance of an inducer varies sensitively with the inducer geometry and this paper deals with solidity as the inducer geometry parameter. The typical performance characteristics of a basic inducer was investigated and tests with another three inducers of which the solidity is different from each other were performed, so the effect of solidity on the inducer performance was experimentally investigated. For a fixed flow coefficient, required NPSH of the inducer did not follow the conventional similarity rule, so this paper suggested another empirical formula. The hydraulic and suction performance was measured at four cases of the tip solidity ranged from 1.32 to 2.76. As long as the tip solidity had the value above 1.84, the hydraulic and suction performance of the inducer increased with decrease in the tip solidity. With further decrease in the tip solidity up to 1.32, however, inducer head decreased and the suction performance dropped sharply.

• The KSFM Journal of Fluid Machinery
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• v.9 no.2 s.35
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• pp.25-29
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• 2006

Computational and experimental studies on the forward-sweep inducer for the rocket-engine turbopump are presented in comparison with the conventional backward-sweep inducer. Computational results show that back flows at the inlet decrease in the case of forward-sweep inducers compared to the back-ward inducer. Moreover, the low pressure region at the back flow is decreased, which is presumed to improve the suction performance of the inducers. Experimental results show that the suction performance of the forward-sweep inducer is almost the same as that of the backward-sweep inducer although it has smaller inlet tip diameter and shorter length. The efficiency of the forward-type inducer is found better than that of the backward-sweep inducer due to the small size of back flows.

• The KSFM Journal of Fluid Machinery
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• v.13 no.3
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• pp.49-53
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• 2010

The computational studies on the cavitating flow around a turbopump inducer were performed to see the effect of the cavitation on the performance of the inducer. The development of cavities around the inducer blades and the head drop of the inducer are observed as the inlet pressure reduces. The change of the backflow at the inducer inlet is also observed with the development of the cavities. The size of the backflow reduces as the inlet pressure is reduced due to the development of the cavities around the blades. The predicted suction performances of the inducer were compared with the experimental results. The results show that the computations overestimate the suction performances of the inducer than the experiments.

• The KSFM Journal of Fluid Machinery
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• v.17 no.3
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• pp.13-18
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• 2014

Computational and experimental studies on a forward-sweep inducer for turbopumps were performed to see the effect of the blade sweep on the suction performance of the inducer. Computational results show that backflows at the inlet decrease in the case of the forward-sweep inducer by inhibiting pre-rotation of the inflow and the low pressure region near the tip also diminishes, which is presumed to improve the suction performance of the inducer. The predicted suction performance of the inducer is compared with the experimental result. The result shows that the computation overestimates the suction performance of the inducer compared to the value from the experiment.

• 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.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.41-46
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• 2002

Flow field downstream of an inducer was measured to see the flow and performance characteristics of a turbopump inducer. A large axisymmetric collector instead of a volute casing was installed to obtain circumferentially uniform flow - without interaction of the inducer and the volute. A conventional 3-hole probe was used to measure the flow. At inducer exit axial component of absolute velocity decreased on hub region with decrease in flow rate. Tangential velocity component static pressure, and total pressure increased from hub to tip. Relative flow angle from tangential direction was a little higher than outlet blade angle at flow coefficient $\varphi$=0.087 and 0.073. Dynamic pressure was $53\%$ of the mean total pressure at inducer exit at $\varphi$=0.073.

• The KSFM Journal of Fluid Machinery
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• v.6 no.4 s.21
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• pp.38-44
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• 2003

Flow field downstream of an inducer was measured to see the flow and performance characteristics of a turbopump inducer. A large axisymmetric collector instead of a volute casing was installed to obtain circumferentially uniform flow - without interaction of the inducer and the volute. A conventional 3-hole probe was used to measure the flow. At inducer exit, axial component of absolute velocity decreased on hub region with decrease in flow rate. Tangential velocity component, static pressure, and total pressure increased from hub to tip. Relative flow angle from tangential direction was a little higher than outlet blade angle at flow coefficient ${\phi}=0.087$ and 0.073. Dynamic pressure was $53\%$ of the mean total pressure at inducer exit at ${\phi}=0.073$.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.519-522
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• 2006

Experimental and computational studies on an turbopump inducer with and without a bearing strut were performed to evaluate the effects of a strut on the performance of an inducer. Global performance data such as head rise and efficiency, and detailed flow characteristics such as surface static pressures were measured and compared with computational results. Generally a good agreement is observed between experimental and computational results, but some discrepancies are observed due to complex flow features such as backflows at the inlet and strut/inducer interactions. For the flow rates where the backflow region is large, installing a strut enhanced the hydraulic performance of the inducer by diminishing the size of the backflows. The results also show that the strut has negligible effect on the suction performance of the inducer.