• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.3
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• pp.56-60
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• 2017

In hypersonic aircraft, increase of aerodynamic heat and engine heat leads heat loads in airframe. It could lead structural change of aircraft's component and malfunctioning. Endothermic fuels are liquid hydrocarbon fuels which are able to absorb the heat load by undergoing endothermic reactions. In this study, exo-tetrahydrodicyclopentadiene was selected as a model endothermic fuel and experiments were investigated in endothermic fuel cooling system with zeolite catalyst. Three shapes of catalysts have been manufactured and endothermic characteristics were recovered. Bineded catalyst showed higher heat absorption and conversion than other two zeolite catalysts. In product distribution, binded catalyst showed higher aromatics composition.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.839-845
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• 2021

In this study, it shows the efficiency of each refrigerant through simulation method for ORC (Organic Rankine Cycle) power generation that converts waste heat discarded by ship exhaust into electricity for the purpose of reducing CO₂ emission and increasing ship waste heat recovery. by Simulation was performed with waste heat from the exhaust gas which is relatively high temperature and cooling sea water which is relatively low temperature from ships. As a result of the sea water cooling ORC power generating system, efficiency of the working fluid with R717 is highest as a 2.86 % and the next working fluid is R152a, R134a, R143a and R125a.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.299-304
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• 2005

The design procedures of full-scale combustion chamber with chamber pressure of 53bara, mass flow rate of 90kg/s, combustion efficiency of $94\%$ and specific impulse at ground of 253sec were described. The details of combustion performance and geometrical parameters were also given. Full-scale combustion chamber consists of the combustor head with injector/baffle and the chamber/nozzle with regenerative cooling channels. The design results of combustion chamber with ablative materials, detachable injector head with SUS baffle or baffle injector and chamber body for ground hot firing tests were given in this paper.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.181-189
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• 2007

The technical requirements to the propellant of rocket engine using chemical energy are developed from the point of its performance, design and the exploration. The propellant, i.e. to get higher energy, to increase the cooling effect, and to be used in safety and comfort should be made. So from these aspect the technical requirements were written by the factors of physical chemistry. And the propellant combination used recently in Launch vehicles is liquid Oxygen and Kerosene, the main characteristics of this Kerosene as a fuel were reviewed. The toxicity and the safety of Kerosene, in specially, require the attention of the users. Also, it would be used in the development of Korean Kerosene by the comparative review of the several Kerosenes in Abroad.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.40-46
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• 2006

A 30-tonf-class fullscale thrust chamber for the application to a Low-Earth-Orbit Space Launch Vehicle has been combustion tested over the wide ranges of a mixture ratio and a chamber pressure. The thrust chamber designed for a pump-fed open cycle engine was tested with an ablative chamber instead of a regenerative one for the initial evaluation of its performance and function. The test results revealed stable combustion characteristics. The hardware survived the harsh environment and showed very sound functional characteristics. The measured combustion efficiency turned out to be 95% and a specific impulse at sea level was estimated as 254sec, which are comparable to or above the predetermined design values.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.69-73
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• 2009

Combustion test results of 1/2.5-scale thrust chamber for 75tonf-class liquid rocket engine were described. The thrust chamber has chamber pressure of 60 bar, propellant mass flow rate of 89 kg/s, and nozzle expansion ratio of 12. The combustion tests were conducted to verify the combustion performance, the regenerative cooling performance and the durability of thrust chamber at design point condition, and then were performed to confirm the operation and the combustion performance at low combustion pressure condition. All the tests had been successfully executed without the damage of the hardware. These test results present a possibility of hot firing test at low combustion pressure condition, and can be used as fundamental data to predict the combustion performance at design point condition for 75 tonf thrust chamber.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.3
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• pp.65-71
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• 2003

In this research, we make the thin wall chamber to the measurement of heat flux of using a Kerosene/LOx liquid rocket engine's thrust chamber. The wall thickness is one millimeter. We measured outside wall temperature of thrust chamber by nine thermocouple. We suppose the system to the one-dimension unsteady state, and so the heat flux and heat transfer coefficient of thurst chamber are calculated using one-dimensional the transient energy equation by outside wall temperature. In this case, O/F ratio is 2.0, experimental variation is chamber pressure and we got the heat transfer coefficient of the proportion relation of 0.88 times for the chamber pressure.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.4
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• pp.81-88
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• 2013

It was designed and tested at the design point that an oxidizer rich preburner for a staged combustion liquid rocket engine propelled by kerosene and LOx. The oxidizer rich preburner was designed as some of LOx injected from the mixing head was burned with kerosene and the rest of LOx injected from injection holes in the regenerative cooling chamber was vaporized by combustion gas. The preburner is operated at OF ratio of 60 and combustion pressure of 20 MPa. The Preburner has a honey-comb type mixing head with simplex swirl injectors, a turbulence ring improving combustion stability and uniformity of product gas temperature distribution, and a nozzle simulating the duct. With the combustion test results at the design point, the oxidizer rich preburner showed high combustion stability and uniformity of product gas temperature distribution.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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• pp.159-164
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• 2009

Cooled EGR system is an effective method for the reduction of $NO_x$ emission and PM emission from a diesel engine. Proper choice of wavy cooling fins and gas tubes is a key factor of cooled EGR system. As a part of solutions for energy crisis and environmental problems, hybrid vehicles mounted with diesel engines are under development globally. This study investigates the cooled EGR systems for hybrid diesel engine with the specifications of both optimized wavy cooling fins and improved shape of structure to verify the heat exchange efficiency, outlet temperature and gas pressure drop of cooler by means of numerical analyses and rig performance tests. The output of this study will be applied to a 2.0L hybrid diesel engine which is being developed for domestic and overseas market.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.99-106
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• 2011

This paper deals with engine room layout design optimization of fuel cell electric vehicle (FCEV), which has been proposed as a potential alternative to fossil fuel depletion. Investing the great R&D efforts, the global vehicle manufacturers, especially Honda motor corporate, have shown not prototype vehicle but commercial vehicle using fuel cell in the market recently. In this paper, we analyze cooling performance and flow characteristic in the engine room of newly FCEV, in addition we suggest the optimization process for engine room layout design optimization. The two radiators in the vehicle for fuel cell stack and electronic components cooling have been analyzed and their performance are obtained in terms of cooling performance ratio (CPR). The value of CPR should always be less than one and based on criteria, we have achieved the optimum cooling performance of radiators for stack and electronic components. Aerodynamic performance is evaluated in terms of drag coefficient, improved through underbody modification using air devices.