• Journal of the Korean Society of Propulsion Engineers
• /
• v.25 no.1
• /
• pp.50-57
• /
• 2021

Engine cool down process is necessary for the liquid rocket engines using cryogenic propellants in order to meet the requirement of engine inlet temperature. This paper evaluates the cool down characteristics of oxidizer supply pipeline and engine in prechill process prior to the engine firing tests, and calculate the quantity of liquid oxygen consumption.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.498-501
• /
• 2012

The Model Rocket Engine Test Facility has been improved to develop the Korea Space Launch Vehicle II(KSLV-II). The modified Model Rocket Engine Test Facility will be used to develop 7-tonf class liquid rocket engine combustor. The test result and test technique acquired from this facility will be used to develop the high performance liquid rocket engine combustor. This paper describes the modified Model Rocket Engine Test Facility for a Sub-scale model test of the 7-tonf class combustor.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.454-456
• /
• 2012

Conceptual design results of a thrust chamber for a 7 tonf-class liquid rocket engine of KSLV-II 3rd stage were described. The engine system for KSLV-II 3rd stage is pump-fed system, the thrust chamber has vacuum thrust of 6.9 tonf, vacuum specific impulse of 336.9 sec, chamber pressure of 70 bar, nozzle expansion ratio of 94.5, total propellant mass flow rate of 20.5 kg/s, mixture ratio(O/F) of 2.45. The thrust chamber consists of mixing head with 90 coaxial swirl injectors and regeneratively combustion chamber cooled by kerosene.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.3
• /
• pp.96-102
• /
• 2016

The 7tonf-class power pack test at turbopump test facility in Naro space center was performed for confirmations of starting/running/ending operation characteristics before 7tonf rocket engine hot-firing test. The dynamic pressure mounted on a combustion chamber of gas generator is measured under 0.2 bar which does not conditioned to the unstable combustion. The analysis results of RPM and acceleration sensors mounted on the turbopump, the power pack test was performed to the estimated RPM with the stable combustion.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.22 no.1
• /
• pp.89-97
• /
• 2018

The test results of a 7-tonf-class engine for the third-stage engine of KSLV-II are presented. Hot-firing tests performed with two engineering model engines are classified into ground tests and high-altitude tests according to the test conditions. The operability verification of the engines were carried out through short and long duration tests. The full duration test performed for the durability verification of the engines revealed a few of items to be improved. Synthetically, encouraging data of adding power to engine development were obtained from the test results. New engines based on these results will be manufactured and consistently verified through hot-firing tests.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.451-453
• /
• 2012

Conceptual design and manufacturing scheme of a gas generator for 7 tonf class rocket engine were described. The combustion chamber pressure, O/F ratio, and total flow rate were decided to be 6 MPa, 0.321, and 1 kg/s respectively in consequence of the engine system design. Based on the parameters conceptual design of the gas generator was carried out and its outer dimension was about ${\Phi}100{\times}250mm$. Most parts of the gas generator to be jointed together by brazing or TIG welding and, if possible, the strength and leakproof tests are to be conducted in every step for checking the welding section.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.24 no.4
• /
• pp.55-65
• /
• 2020

In this paper, development and acceptance test results of 75-tonf class liquid rocket engine gas generators are described. Up to now, more than 330 times and cumulative time of 7,000 seconds gas generator autonomous tests have been carried out with 44 gas generator models. Through the tests it was verified that 75 tonf gas generator shows very reliable and reproducible characteristics in terms of chamber pressure, combustion efficiency, pressure loss, combustion stability, burnt gas temperature, and etc. 5 gas generators which are the last series of 75 tonf gas generator for the Korea Space Launch Vehicle II, will be manufactured until end of 2019 and their acceptance tests will be executed at the first half of 2020.

• Journal of Aerospace System Engineering
• /
• v.11 no.4
• /
• pp.48-53
• /
• 2017

Liquid rocket engines (LREs) are very complex systems that include combustion chambers, turbopumps, gas generators, ducts and tubes, valves and etc. Most components of the LREs require higher than or equal to level 6 IT (ISO Tolerance). The components along with pipe line and/or tubing must dispose not to interfere each other. In addition, effectiveness of maintenance and service after assembling should be considered when the allocation of the components are determined. Especially at the stage of the development, tolerance accumulations or unpredictable errors may result in misalignment and/or mismatches at interfaces of the parts. Namely, it is the engine assembling process that many inherent risks are realized and crises or incidents occur. Therefore, a rapid reaction system should be prepared. In this research, 7 tonf class liquid rocket assembling process was studied and actual building steps were introduced.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.457-460
• /
• 2012

Design and fabrication of a sub-scale thrust chamber for verification of 7 tonf-class thrust chamber injectors were described in this paper. The 7 tonf-class thrust chamber consists of mixing head with 90 coaxial swirl injectors and regeneratively combustion chamber cooled by kerosene. The coaxial swirl injectors with different pressure drop and recess number were designed for 7 tonf full-scale thrust chamber. By applying the designed injectors to the sub-scale thrust chamber before applying them to the full-scale thrust chamber, the injector performance and functioning were verified. The sub-scale thrust chamber consists of 19 injectors, has chamber pressure of 70 bar, total propellant mass flow rate of 4.3 kg/s, mixture ratio(O/F) of 2.45.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.493-497
• /
• 2012

The rocket engine test facility(ReTF) was improved for hot firing tests of 7 ton-class liquid rocket engine combustion chamber, which will be used for the third stage of the Korea Space Launch Vehicle II(KSLV-II), considering convenience of operation and maintenance, flexibility and safety. In this paper, main modifications and functions of improved ReTF were described. 초 록