• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.9-14
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• 2002

A homogeneous premixed charge compression ignition engine has been experimentally studied far the reduction exhaust emissions of diesel engines. In this study, the gasoline fuel is injected into the intake manifold to from homogeneous pre-mixture in the combustion chamber and then this pre-mixture is ignited by small amount of diesel fuel directly injected into the cylinder. In the premixed charge compression ignition engine, NOx and smoke concentration of the exhaust emissions were reduced simultaneously as compared with the conventional diesel engine. The combustion characteristics of premixed charged diesel engine such as the power output, the rate of heat release, and the other characteristics are discussed.

• Journal of Biosystems Engineering
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• v.17 no.1
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• pp.5-17
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• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.224-230
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• 2014

The purpose of this paper is to investigate the performance of supplemental cooling and heating system equipped with the 1 kW thermoelectric module. The system consist of 96 thermoelectric modules, heat sink with louver fin and water cooling jacket which is attached on the hot side of the thermoelectric module. The cooling and heating performance test of the thermoelectric system is conducted with various conditions, such as intake voltage, air inlet temperature, air flow volume, water inlet temperature and water flow rate at calorimeter chamber in consideration of environmental conditions in realistic vehicle drive. The experimental results of a thermoelectric system shows that the cooling capacity and COP is 1.03 kW, and 1.0, and heating capacity and COP is 1.53 kW, and 1.5 respectively.

• Solar Energy
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• v.12 no.3
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• pp.84-93
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• 1992

Solar assisted heat pump with freon circulating system has been developed. Revising the cool chamber(flower storage) with the solar thermal hot water producing system, the more amount of hot water can be produced, which can be even used for room panel heating. The compressor was cooled by water jaket instead of air cooled so that the system energy efficiency was improved quite well.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.2
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• pp.215-222
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• 1986

This paper presents the results of investigation, the aim of which was to predict theoretically the processes of thermodynamic cycle of M-combustion chamber type diesel engine. The combustion characteristics in cylinder are evaluated from the energy equation for an thermodynamic system in engine cylinder. In order to predict the combustion pressure in cylinder, the engine is divided in various control volumes. The simulation results of combustion characteristics show that the comparison of computed and measured values brings about the good coincidence.

• 한국연소학회:학술대회논문집
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• 1998.10a
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• pp.69-77
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• 1998

In order to meet the stringent emission regulations, fast light-off of a catalyst is essential to reduce the HC and CO emissions during cold start. Cranking Exhaust Gas Ignition (CEGI) method developed in this study showed that the catalyst reaches the light-off temperature in a few seconds after cold start. The CEGI system cuts off the ignition signal for a few seconds during the cranking period. so the unburned fuel-air mixture bypasses the combustion chamber and flows through the exhaust manifold. When the unburned mixture reaches two glow plugs installed upstream of the catalyst, it burns and releases the thermal energy to heat up the catalyst. Results from the FTP-75 tests showed that the exhaust emissions with the CEGI reduced by 47.7% for THC and by 88.6% for CO in the cold-transient phase of the test.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.2 s.17
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• pp.5-12
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• 2004

The erosion wear of gun barrel occurs due to heat and chemical reactions. The high pressure and temperature in chamber increase the erosion wear. It is known that the metal phase transfer is the primary wear factor in a gun barrel under high temperature. In this paper, the tool of wear prediction in high pressure gun tube has been developed. The program developed has three modules such as DIRECT(interior ballistics analysis module), INVERSE(gun design module), and WEAR(wear prediction module). The prediction of wear was compared with the experimental data which was collected in the field unit. The prediction results shows good trend with the collected data.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.109-115
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• 2007

Airframe-integrated Scramjet engines of NASA Langley type consist of a compressor, a combustion chamber and a nozzle. When some disturbances occur in one module of the engine, its influences are propagated to other modules. In this study, it is investigated numerically how shock waves were caused by thermal choking in one module propagate upstream and how they influence adjacent modules. The calculations are carried out in 2-dimensional supersonic viscous flow model using explicit TVD scheme in generalized coordinates. The adverse pressure gradient caused by heat addition brings about separation of the wall boundary layers and formation of the oblique shock wave that proceed to upstream. This moving shock wave formed one module blocks the flow coming into the adjacent modules, which makes the modules unstarted.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2856-2861
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• 2008

A catalytic burner has been developed to utilize thermal energy from the fossil fuel without nitrogen oxides (NOx) emission. The burner is shaped into a mat to maximize the heating surface. Premixed combustion has been developed to be used in a closed chamber, such as a radiation type industrial dryer. The burner yields the thermal energy in the form of thermal radiation in the infrared regime, which is proved to be effective to dry organic substances for low moisture condition. Thermal efficiency including the sensible heat is better correlated to the moisture compared to the dry rate.

• Journal of the Semiconductor & Display Technology
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• v.7 no.1
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• pp.41-45
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• 2008

We studied the electrical characteristics of low-k SiOCR interlayer dielectric(ILD) films fabricated by plasma enhanced chemical vapor deposition (PECVD). The precursor bis-trimethylsilylmethane (BTMSM) was introduced into the reaction chamber with the various flow rates. The absorption intensities of Si-O-$CH_x$, bonding group and Si-$CH_x$, bonding group changed synchronously for the variation of precursor flow rate, but the intensity of Si-O-Si(C) responded asynchronously with the $CH_x$, combined bonds. The SiOCH films revealed ultra low dielectric constant around 2.1(1) and reduced further below 2.0 by heat treatments.