• Journal of ILASS-Korea
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• v.19 no.4
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• pp.211-215
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• 2014

The main purpose of this study is to provide basic information of droplet soot generation of decane fuel. To achieve this, this paper presents the experimental results on the decane droplet combustion conducted under various ambient pressure($P_{amb}$), and oxygen concentration($O_2$) conditions. At the same time, the experimental study was conducted in terms of soot volume fraction($f_v$) and its maximum value. Also, visualization of single fuel droplet was conducted by high resolution CCD camera and ambient pressure($P_{amb}$) and oxygen concentration($O_2$) was changed by control system. It was revealed that higher ambient pressure($P_{amb}$), and oxygen concentration($O_2$) enhanced the soot generation and improved the maximum soot volume fraction( $f_v$).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.7
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• pp.999-1004
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• 2015

In this paper, the study presents the development of 34kW class cryogenic induction motor using LNG Pump. Operating temperature of an induction motor using LNG Main Cargo Pump is at −163℃. Due to variation of the resistivity, these motor have different torque characteristics. So, it should design to considering the resistivity change. The most important consideration of induction machine operating is cryogenic temperature. If the temperature rise, LNG is vaporized. it is a major cause of pump failure. There are several causes of heat source like coreloss, hysterisysloss, copperloss. This paper analyzed the thermal distribution of the induction motor at rated speed operation.

• Journal of ILASS-Korea
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• v.9 no.1
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• pp.15-20
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• 2004

The post injection effect to enhance aftertreatment devices' performance is essential to meet future stringent emission standards by controlling exhaust gas temperature and emission pollutants. The test has been made with commercial common rail diesel engine by post injection manipulation, to optimize exhaust gas temperature while guarantee low fuel penalty. The optimization was done at 1500, 2000 and 2500[rpm] for 2, 4[bar] condition which show low exhaust gas temperature. The main purpose of this test is dedicated to understand mechanism of exhaust gas temperature rise while optimizing

• Journal of ILASS-Korea
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• v.19 no.3
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• pp.109-114
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• 2014

The main purpose of this study is to provide basic information of droplet burning, extinction process and flame behavior of methanol fuel and improve the ability of theoretical prediction of these phenomena. For the improved understanding of these phenomena, this paper presents the experimental results on the methanol droplet combustion conducted under various initial droplet diameters ($d_0$), ambient pressure ($P_{amb}$), and oxygen concentration ($O_2$) conditions. To achieve this, the experimental study was conducted in terms of burning rate (K) with normalized droplet diameter ($d/d_0$), flame diameter ($d_f$) and flame standoff ratio (FSR) under the assumptions that the droplet combustion can be described by both the quasi-steady behavior for the region between the droplet surface and the flame interface and the transient behavior for the region between the flame interface and ambient surrounding.

• Journal of ILASS-Korea
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• v.19 no.3
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• pp.101-108
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• 2014

The current paper reviews the main characteristics and the operating principles of major fuel atomizers used for gas turbine combustors, including various empirical SMD equations for each atomizers. We have summarized various methodologies for evaluation of the combustion efficiency and for combustor sizing from the selected SMD data. It is found that the combustor sizing as well as the combustion efficiency are totally dependent upon the SMD calculation results, which means that special cares should be taken in choosing the SMD empirical equations.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.500-510
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• 1996

A Direct injection -mixing total -flow -control sprayer was developed and evaluated . The system provided precise application rates and minimized operator exposure to chemicals as well as providing a possibility for recycling container so f unused chemicals that can causes environmental contamination. Chemicals were metered and injected proportionally to the diluent flow rate to provide constant concentrations. The main diluent flow was varied in response to changes in travel speed. Experimental variables of the sprayer were the control interval, the sensitivity of flow regulating valve, the tolerance of control object and the sensitivity of the injection pump system. The optimal performance of the flow control system was with an average response time of 8.5 sec at an absolute steady state of error of 0.067 L/min (0.8% of flow rate). The average response time of the injection rate was -0.53 sec and the coefficient of variation (CV) of concentration was 3.2%.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.2
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• pp.149-153
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• 2003

Besides the fuel spray behavior and combustion chamber shape. an air motion has a key role on exhaust gas emission and performance in a DI diesel engine. A swirl ratio represents the ratio of the intake swirl velocity to the engine speed. The main purpose in this work is to investigate the effects of the swirl ratio to the combustion characteristics. A shroud valve machined to change the swirl ratio. Test was carry out by changing the engine speed, nozzle diameter and swirl ratio in a single cylinder diesel engine. From this study, the optimized combustion was found at swirl ratio 2.7. And it was also found that the increasing the maximum cylinder pressure with an increasing swirl ratio lead to decrease a smoke and to increase NOx.

• Journal of ILASS-Korea
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• v.18 no.1
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• pp.1-8
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• 2013

In this paper an experimental study is presented to investigate the dynamic behavior of impacting droplet onto a liquid film. The main parameters are the droplet velocity and the thickness of the liquid film. Photographic images are presented to show the formation of crown, central jet and disintegrating droplet from the central jet. The emphasis is on presenting the time evolution of crown diameter, crown height, central jet height and the size of disintegrating droplet from the central jet. The diameter and height of crown are higher for faster droplet and thinner liquid film. On the other hand, the height of central jet are higher for faster droplet and thicker liquid film. The size of disintegrating droplet from the central jet heavily depends on the droplet velocity; Larger droplet is produced with faster falling droplets.

• Journal of ILASS-Korea
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• v.22 no.2
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• pp.55-61
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• 2017

This study has investigated the relationship between heat release fluctuations and the flow perturbations in a partially premixed gas turbine combustor using a commercial CFD code. Special focus of the current work is placed on the effect of equivalence ratio on the flame dynamics in a partially-premixed system. As the first step for this combustion dynamics study in the non-perfectly premixed combustor, flame behaviors are modeled and then compared with measured results under both steady and unsteady conditions. The calculated results of the flame transfer function with equivalence ratio fluctuation are found to well capture the main qualitative characteristics of the combustion dynamics for the partially-premixed flames.

• Journal of ILASS-Korea
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• v.22 no.2
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• pp.47-54
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• 2017

$CO_2$ emission regulation will be prescribed and main issue in automotive industry. Mostly, vehicle's fuel efficiency deeply related to $CO_2$ emission is regulated by qualified driving test cycle by using chassis dynamometer and exhaust gas analyser. But, real driving fuel consumption rate depends so much on the individual usage profile and where it is being driven: city traffic, road conditions. In this study, vehicle model of fuel consumption rate for ICEV and PHEV was developed through co-simulation with CRUISE model and Simulink based on driving control model. The simulation results of fuel consumption rate were analysed with on-road vehicle data and compared with its official level.