• Journal of the Korean Society of Propulsion Engineers
• /
• v.13 no.6
• /
• pp.8-16
• /
• 2009

The development of high-pressure sub-scale combustion chambers is described. A total of four high-pressure sub-scale combustion chambers having either a detachable structure of the mixing head and the chamber or a single welded regenerative cooling structure have been developed. The sub-scale combustion chambers have a chamber pressure of 70 bar and propellant mass flow rate of 5.1~9.1 kg/s. The propellant mass flow rate and the recess number of the injector were changed for the improvement of combustion performance and they were validated through hot firing tests. The design and manufacturing techniques of regenerative cooling channel and film cooling to be applied to the full-scale combustion chamber were adopted through the present development and verified.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.591-595
• /
• 2017

Numerical simulations were carried out to analyze thermo-fluid dynamic and missile-motion performance by using two-phase flow model and dynamic grid system. To analyze the interaction among the hot gas, coolant, and mixture flow, Realizable $k-{\varepsilon}$ turbulence and VOF(Volume Of Fluid) model were chosen and a parametric study was performed with the change of coolant flow rate. As a result of the analysis, pressure of the canister showed a large difference depending on the presence or absence of the coolant, and also showed a dependancy on the amount of coolant. Velocity and acceleration were dependent on the canister pressure.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2003.10a
• /
• pp.83-88
• /
• 2003

An analytical study was carried out to evaluate the regenerative cooling characteristics in the liquid rocket engine of a 10tf-thrust level using kerosene as a fuel. As a supplementary cooling method, a radiative cooling was applied to the nozzle extension. It was found out from this work that the cooling system with the regenerative and radiation cooling only is not adaptable as a cooling method for the liquid rocket engine of a 10tf-thrust level using kerosene as a fuel for the 2nd stage of the space launch vehicle. So, additional cooling method, curtain cooling was introduced and analyzed. Curtain cooling was very effective to reduce the thermal and thermo-structural instability.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1996.04a
• /
• pp.100-104
• /
• 1996

신형경수로의 설계 대안으로서 기존 가압경수로와 가압중수로의 단점들을 극복하고, 장점들을 채택한 새로운 중수감속 경수로의 노심 설계를 제안하였다. 기존 가압중수로의 압력관내에 경수를 냉각제로 순환시키며 중수를 감속재로서 압력관 외부에 배치하였으며, 핵연료로서 농축우라늄을 사용하는 설계 개념은 많은 설계 장점을 갖는다. 본 연구에서는 시스템은 기존 CANDU의 설계를 입증기술로서 가능한 그대로 채택하고, 핵연료와 냉각재에 대해 핵설계를 수행하여 핵적 타당성을 검토하였다. 핵연료다발은 월성 2호기 사양을 그대로 사용하여 37봉 핵연료 다발로 하였으며, 농축도, 봉간간격, 핵연료다발간 간격들을 변형시켜 높은 연소도를 확보하면서 냉각재 온도계수와 감속재 온도계수가 음의 안전성을 갖는 원자로가 설계될 수 있음을 확인하였다.

• Journal of the KSME
• /
• v.51 no.12
• /
• pp.51-54
• /
• 2011

이 글에서는 제4세대 원자로로 다시 부각되고 있는 소듐냉각고속로(SFR: Sodium-cooled Fast Reactor)의 활용성, 계통설계 구성 및 공학적 안전설비에 대하여 가압경수로(PWR: Pressurized Water Reactor)와의 차이점을 위주로 소개한다.

• 전기의세계
• /
• v.32 no.7
• /
• pp.419-428
• /
• 1983

본고의 내용은 다음과 같다. 1. 저온을 얻는법 2. 액화장치의 작동원리 3. 저온 냉각제 취급법 4. 저온측정법 5. 저온에서의 물리적 성질 및 응용

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.4
• /
• pp.2021-2026
• /
• 2013

In this study, the effect on the welding angle distortion was reviewed by carrying out a thermal elastic-plastic analysis while changing the cooling condition(width, length, and distance from weld torch to cooling torch) the back of the welding zone for the butt weld joint. The review results revealed that maximum 57% of reduction in the angle distortion was achieved when the distance between weld torch and cooling tip of 25mm, cooling length of 80mm, and cooling width of 30mm were maintained.

• Aerospace Engineering and Technology
• /
• v.7 no.1
• /
• pp.136-141
• /
• 2008

Cylindrical supersonic exhaust diffuser, which utilizes the momentum of high temperature gas exhausted from nozzle, provides simple methods for obtaining stable and low pressure around the propulsion system. Hot zone on which exhausted gas from nozzle exit impinges directly should be cooled to avoid melting of diffuser. This paper describes method and result of subscale high altitude simulation test with water cooling. Subscale gas generator with solid propellant was used for hot gas source and tap water for coolant.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.13 no.3
• /
• pp.419-423
• /
• 1989

The laboratory quench method used in this study is based on plunging a silver cylinder heated to 800.deg. C in to mineral oil and vegetable at given temperature. Experimental apparatus and measuring method followed Korean Industrial Standard. Colling curves at the boundary of the cylinder measured by a silver-alumel thermocouple is recorded throughout the quenching period. Using the cooling curves, the coolingability of the quenching oils at various temperatures were compared and discussed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.11a
• /
• pp.163-170
• /
• 2011

Applicability of regenerative cooling in 2,500 N-class bipropellant thruster using hydrogen peroxide and kerosene was considered for improvement performance and application in various missions. Calculation was performed by one dimensional approach using hydrogen peroxide as a coolant. In designed regenerative cooling thruster, heat flux at nozzle throat was estimated at 18 ~ 20 $MW/m^2$. Designed cooling channel width and height were 2.5 mm and 0.5 mm, respectively. Based on designed cooling channel configuration, flat plate model was manufactured and tested for estimation of pressure drop in cooling channel, and CFD analysis was compared with the test result. The maximum error between CFD analysis and experimental result was approximately 13% and average error was approximately 5%.