• Aerospace Engineering and Technology
• /
• 제7권2호
• /
• pp.157-161
• /
• 2008

This study introduce a newly developed program to calculate the combustion process of combustion chamber and gas generator of liquid rocket engine by use of Gibbs free energy minimization method based on chemical equilibrium. The simulation results of the new program and CEA code of NASA were compared and showed good agreement, thus proving the validity of the newly developed in-house program for combustion analysis.

• Journal of Korean Elementary Science Education
• /
• 제28권4호
• /
• pp.467-475
• /
• 2009

This study is to enquire about ideals on combustion and to propose of teaching program using the history a science in '5. Combustion and Extinguishing' unit of elementary school science textbook in 6th grade. For this purpose, investigation questionnaires based on preceding research and science textbook are developed. The reliability of the questionnaires is .784, and the questionnaires are applied to 247 students in T elementary school in Busan. Through the results of the investigation, scientific conceptions existed in some parts. But some misconceptions still existed especially (question 1), substance's changes (question 7), formation process of product (question 13), combustibles among requirements of combustion. The patterns of the misconception are similar to historical misconceptions about combustion. Besides, the discoveries and inventions of combustion have some points about correcting misconceptions. Thus the five step teaching programs on combustion which were applied to history of the science are suggested. The confidence of the developed programs was verified as being 'excellent' by specialists. This program will be applied to think deeply about combustion in elementary school lesson and useful to introduce the history of science.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 한국추진공학회 2010년도 제35회 추계학술대회논문집
• /
• pp.93-97
• /
• 2010

The energy balance program which can balance the relations among energy, mass flow, pressure in the staged-combustion cycle of the liquid rocket engine has been developed. The modular approach has been chosen for the analysis; the engine cycle consists of the elements from the predefined component analysis program. The engine with the staged-combustion cycle has been decomposed into several principal component modules, such as a thruster chamber, turbopumps, turbines, supply system components and a pre-burner. The program has been verified with comparison of the results to the selected data of the space shuttle main engine.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 한국추진공학회 2009년도 춘계학술대회 논문집
• /
• pp.402-405
• /
• 2009

Present review introduces the constant volume combustion (CVC)-based hypersonic propulsion system development program recently initiated by DARPA for the hypersonic cruse vehicle (HCV).

• Transactions of the Korean Society of Mechanical Engineers
• /
• 제18권10호
• /
• pp.2787-2796
• /
• 1994

The modeling of combustion process is an important part in an engine simulation program. In this study, calculated results using a conventional B-K model and the other model which is called GESIM were compared with experimentally measured data of a three-cylinder spark-ignition engine under wide range of operating conditions. The burn rates calculated from the combustion models were compared with the burn rate calculated from the one-zone heat release analysis that uses measured pressure data as an input data. As a result of the two models' comparison, the GESIM combustion model conformed to be closer to the data acquired from the experiment in wide operating ranges. The GESIM model has been improved by introducing a variable that considers the flame size, the area of flame conacting the piston surface into the model, based on the comparison between the experimental result and the calculated results. The improved combustion model predicts experimental results more precisely than that of GESIM combustion model.

• Journal of the Korean Society for Heat Treatment
• /
• 제16권3호
• /
• pp.148-158
• /
• 2003

In this study, a user oriented CFD program for optimum design of a regenerative combustion furnace, REBURN was developed. For user's convenience, user friendly Graphic User Interface was made and the renumbering interface program was developed in order to directly input any generated mesh system from ICEM CFD/FEA. Also an automatic processing system for switching mode was developed. The program was verified through compahng with commercial CFD code about regenerative combustion furnace. Then, numerical simulation of real walking beam furnace used in real industry was performed and the parametric analysis was studied about the arrangement mode. As a results, the uniform temperature was appeared in the cross mode.

• Journal of the Korean Society of Combustion
• /
• 제18권3호
• /
• pp.54-60
• /
• 2013

This paper shows a general development process for aircraft gas turbine combustors. As a first step for developing the preliminary combustor design program, several combustor sizing methodologies using reference area concepts are reviewed. There are three ways to determine the reference area; 1) combustion efficiency approach, 2) pressure loss approach, 3) velocity assumption approach. The current study shows the comparisons of the calculated results of combustor reference values from the pressure loss and velocity assumption approaches. Further works are required to add iterative steps in the program using more reasonable values of pressure loss and velocities, and to evaluate the sizing results using data for actual combustor performance and sizes.

• Journal of ILASS-Korea
• /
• 제22권3호
• /
• pp.116-121
• /
• 2017

Pre-combustion chamber type indirect diesel engines have different combustion characteristics compared with those of common rail direct injection engine. The CONVERGE, specific engine CFD program, was used to simulate hollow cone spray model and combustion. The air-fuel mixture flow propagating from pre-combustion chamber to cylinder was concentrated at top half and center of the pre-combustion chamber throat. Stronger mixture flow was formed at smaller and longer throat cases. As a result, thermal efficiency and fuel consumption were improved for modified throat shape and the soot emission was also reduced.

• Journal of the Korean Wood Science and Technology
• /
• 제46권2호
• /
• pp.189-201
• /
• 2018

Intumescent system is a highly effective flame retardant technology that takes advantage of the mechanism of foaming and carbonization. In order to materialize Intumescent system, it is necessary to use reinforcement material to improve the strength of the material. In this study, we used kenaf as a natural fiber to manufacture intumescent/EVA (ethylene vinyl acetate) composites to improve mechanical and flame retardant performance. Finally two materials with different particle shape are applied to one system. Therefore, the influence factors of the particles with different shapes on the composite material were analyzed based on the tensile test. For this purpose, we have used the tensile strength analysis model and confirmed that it can only act as a partial strength reinforcement due to weak binding force between the matrix and particles. In the combustion characteristics analysis using cone calorimeter and UL 94, the combustion characteristics were enhanced as the content of Intuemscent was increased. As the content of kenaf increased, combustion characteristics were strengthened and carbonization characteristics were weakened. Through the application of kenaf, it can be confirmed that elastic modulus improvement and combustion characteristics can be strengthened, which confirmed the possibility of development of environmentally friendly flame retardant materials.

• Journal of Biosystems Engineering
• /
• 제17권1호
• /
• pp.5-17
• /
• 1992

To develop an analytic method of combustion characteristics in a small sized and single cylinder type diesel engine for a power tiller, 1) the theoritical analysis of combustion gas in engine cylinder was performed based on thermoscience and 2) the computer program which could be used to calculate those values of the apparent burning rate, the heat loss, the gas temperature and the fuel-air equivalence ratio with the experimental cylinder pressure data, was developed. This method would provide the practical and quantative data for the diesel combustion process. Through the use of this method, following details would be obtained: 1) the application in the modeling of combustion process without detail knowledeg of combustion process, 2) the basis for the complete modeling of diesel engine, and 3) the basic information for the design of combustion chamber by the prediction of engine performance.