• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.11-17
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• 2009

Hot-fire test of a turbopump for a gas generator cycle rocket engine of 30 ton class was carried out in real propellant environment. Liquid oxygen and kerosene were used for the oxidizer pump and the fuel pump, respectively, while hot gas produced by the gas generator was supplied to the turbine. A part of the propellant discharged from the pumps was provided to the gas generator. The turbopump was run stably at both on-design and off-design conditions, satisfying all the performance requirements. This paper describes one of the test cases, where the turbopump was run for 120 seconds at three different operating modes in one test. In terms of performance characteristics of pumps and turbine, the results from turbopump assembly test using real propellant showed a good agreement with those from the turbopump component tests using simulant working fluid.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.1
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• pp.69-77
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• 2005

To optimize and limit the axial length of the baffle of the KSR-III engine, stability rating tests using pulse gun as one of artificial disturbance devices have been done. Generally a rocket engine can be considered to be dynamically stable if a certain imposed external perturbation or pressure oscillation in rocket combustion chamber could be suppressed within a short time period. Decay time and other parameters for the evaluation of stabilization ability of an engine to external perturbation have been analyzed to quantify stabilization capacity of engine, in other words, dynamic stability margin. Baffle not covering flame zone enough which can be considered as collision region of injector wasn't be able to suppress external perturbation sufficiently. The limit of combustion stability margin of engine is assumed to be 50 mm length baffle of the KSR-III engine.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.359-365
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• 2008

Turbopump test for a 30-ton-thrust liquid rocket engine was carried out using real-propellant. Liquid oxygen, kerosene, cold hydrogen gas were used for the oxidizer pump, the fuel pump, the turbine, respectively. The turbopump was run stably at the design and off-design conditions and the performance requirements were satisfied, which implies that the turbopump development at the engine subsystem level is successfully accomplished in the point of performance validation. This paper presents the results of a test where the turbopump was run for 75 seconds at three operating modes. In terms of performance characteristics of pumps and turbine, the results from turbopump assembly test using real-propellant showed a good agreement with those from the turbopump component tests using simulant working fluid.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.4
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• pp.85-93
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• 2015

Liquid rocket engines of KSLV-II employ a turbopump feed system for propellants. A turbopump real-propellant test facility based on liquid oxygen and kerosene has been constructed for the experimental verification of the turbopump performance using the real media of propellants(i.e., LOX/Kerosene). The verification tests of sub-systems were performed such as LOX/kerosene feed system and alcohol burner system. Finally, the performance of the whole system was executed and verified through a sets of validation tests with the development model of the KSLV-II turbopumps. It has been confirmed that the test facility satisfies the operating conditions and time of the turbopump at the design and off-design performance test using real-propellant.

• Journal of the Korean Society of Propulsion Engineers
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• v.13 no.6
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• pp.1-7
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• 2009

The gas turbine engine performance is greatly relied on its component performance characteristics. Generally, acquisition of component maps is not easy for engine purchasers because it is an expensive intellectual property of gas turbine engine supplier. In the previous work, the maps were inversely generated from engine performance deck data, but this method is limited to obtain the realistic maps due to calculated performance deck data. Therefore this work proposes newly to generate more realistic compressor map from experimental performance test data. And then a realistic compressor map can be generated form those processed data using the proposed extended scaling method at each rotational speed. Evaluation can be made through comparison between performance analysis results using the performance simulation program including the generated compressor map and on-condition monitoring performance data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.10
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• pp.102-111
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• 2004

The procedure of design and manufacture of sub-scale combustor using bipropellant swirl injector with external mixing for a liquid rocket engine are described. The results of cold flow test, ignition test and combustion test of the sub-scale combustor are also given in this paper. The sub-scale combustor uses liquid oxygen(LOx) and kerosene as propellants and has a injector head, an ablative material combustor wall and a water cooled nozzle. The injector head has LOx manifold, fuel manifold, fire face plate, one center swirl injector and 18 main swirl injectors. The cold flow, ignition and combustion tests were successfully performed without damage of combustor. Results of hot firing tests show that combustion efficiency meets the target of design and operations of start and stop cyclogram are stable and high frequency combustion instability does not occur.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.1059-1065
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• 2010

An analysis was conducted to predict the hydraulic performance of a reactor coolant pump (RCP) of SMART at the off-design as well as design points. In order to reduce the analysis time efficiently, a single passage containing an impeller and a diffuser was considered as the computational domain. A stage scheme was used to perform a circumferential averaging of the flux on the impeller-diffuser interface. The pressure difference between the inlet and outlet of the pump was determined and was used to compute the head, efficiency, and break horse power (BHP) of a scaled-down model under conditions of steady-state incompressible flow. The predicted curves of the hydraulic performance of an RCP were similar to the typical characteristic curves of a conventional mixed-flow pump. The complex internal fluid flow of a pump, including the internal recirculation loss due to reverse flow, was observed at a low flow rate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.537-541
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• 2009

The gas turbine engine performance is greatly relied on its component performance characteristics. Generally, acquisition of component maps is not easy for engine purchasers because it is an expensive intellectual property of gas turbine engine supplier. In the previous work, the maps were inversely generated from engine performance deck data, but this method is limited to obtain the realistic maps due to calculated performance deck data. Therefore this work proposes newly to generate more realistic compressor map from experimental performance test data. And then a realistic compressor map can be generated form those processed data using the proposed extended scaling method at each rotational speed. Evaluation can be made through comparison between performance analysis results using the performance simulation program including the generated compressor map and on-condition monitoring performance data.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.3
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• pp.16-22
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• 2010

The gas turbine engine performance relies greatly on its component performance characteristics. Generally, engine manufacturers do not provide engine purchasers the component performance characteristics which can be obtained by lots of experimental tests at various operating conditions and big amount of expenses. In previous works the component maps have mostly been generated by scaling from a similar component map. However this scaling method has large error at off design points, specially in high altitude operation. Therefore this work proposes an inverse modeling method that can generate components maps of PT6A-67A turboprop engine using performance data provided by the engine manufacturer. In addition, evaluation can be made through comparison between performance analysis results using the performance simulation program including the generated compressor map and performance data.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.5
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• pp.1-9
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• 2013

Variable area nozzle, where both throat and exit area vary, is required for optimal expansion and optimal nozzle shape upon operation of after-burner. Steady-state and transient analyses are carried out for each condition with and without afterburner operation and as a function of the location of the nozzle flap. Effects of that nozzle displacement on flow and thrust characteristics are analyzed from numerical results. With variable area nozzle adopted, the combustion field is variable in time, leading to periodically variable thrust. For off-design conditions, flow separation shows up due to over expansion at the flap tips and shock wave does in the nozzle due to under expansion. The undesirable phenomena can be solved by control of variable area nozzle.