• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.4
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• pp.415-421
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• 2013

This study describes the aerodynamic design procedure for the axial turbines of a small heavy-duty gas turbine engine being developed by Doosan Heavy Industries. The design procedure mainly consists of three parts: namely, flowpath design, airfoil design, and 3D performance calculation. To design the optimized flowpath, through-flow calculations as well as the loss estimation are widely used to evaluate the effect of geometric variables, for example, shape of meridional plane, mean radius, blades axial gap, and hade angle. During the airfoil design procedure, the optimum number of blades is calculated by empirical correlations based on the in/outlet flow angles, and then 2D airfoil planar sections are designed carefully, followed by 2D B2B NS calculations. The designed planar sections are stacked along the spanwise direction, leading to a 3D surfaced airfoil shape. To consider the 3D effect on turbine performance, 3D multistage Euler calculation, single row, and multistage NS calculations are performed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.11a
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• pp.105-108
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• 2001

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.127-128
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• 2006

• Journal of Drive and Control
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• v.20 no.4
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• pp.155-156
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• 2023

• Journal of the Korean Society of Industry Convergence
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• v.21 no.6
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• pp.355-360
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• 2018

The product developed in this study is a ceramic catalyst filter for 1 ton heavy-oil boiler that can simultaneously process dust and nitrogen oxides. This has been developed for simultaneous processing of nitrogen oxides and dust at high efficiency of hot exhaust gas (approximately $300^{\circ}C$) generated after burning 1 ton heavy oil boiler. Ceramic catalytic filters for 1 tonne heavy-duty glass display are technologies that remove 90% of dust and 85% or more of nitrogen oxides. This is an improved new technology to integrate exhaust ventilation and desiccation devices into one, thereby reducing the production process and improving the economy. To this end, the performance test of the catalytic filter for heavy oil boilers was carried out, and the durability of the PLC circuit was constructed.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.6
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• pp.487-495
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• 1997

The most desirable diesel oxidation catalyst (DOC) should have the properties of oxidizing CO, HC and SOF effectively at low exhaust gas temperature while minimizing the formation of sulfate at high exhaust gas temperature. Precious metals such as platinum and palladium have been known to be sufficiently active for oxidizing SOF and also to have high activity for the oxidation of sulfur dioxide $(SO_2)$ to sulfur trioxide $(SO_3)$. There is a need to develop a highly selective catalyst which can promote the oxidation SOF efficiently, on the other hand, suppress the oxidation of $SO_2$. In this study, a Pt-V catalyst was prepared by impregnating platinum and vanadium onto a Ti-Si wash coated ceramic monolith substrate. A prepared Pt-V catalytic converter was installed on a heavy duty diesel engine and the effect of fuel sulfur on particulate matter (PM) of heavy duty diesel engine was measured. The effect of fuel sulfur on PM of Pt-V was also compared with that of a commercialized Pt catalyst currently being used in some of the heavy duty diesel engines in advanced countries. Only 1 $\sim$ 3% of sulfur in the diesel fuel was converted to sulfate in PM for the engine without catalyst, but almost 100% of sulfur conversion was achieved for the engine with Pt catalyst at maximum loading condition. In the case of Pt-V catalyst, there was no big difference in conversion with the base engine even at maximum loading condition. The reason of SOF increase according to the increase of suflate emission was identified as the washing off effect of bound water in sulfate.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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• pp.1589-1597
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• 2006

Nowadays, Korean consumers prefer drum-type washing machines to pulsator-type washers. Washing is a complex process involving the interaction of numerous physical and chemical influences. The main factors in the washing operations are the washing chemistry of the detergent along with the mechanical input, the wash temperature, and the time provided by the washing machine. Heavy-duty detergents that are used in drum-type washing machines contain different components from those used in vertical-axis washing machines. The bath ratio and the mechanical actions to which laundry is subjected are different between the drum-type and the vertical-axis washing machines. In this study we examined the effects of wash temperature, wash time, detergent concentration, and revolution speed on the removal of soils from artificially soiled cloths in a drum-type washing machine with heavy-duty commercial detergent. We used multiple regression analyses to find the relative importance of the factors and the optimum washing conditions. The results of these experiments showed that the washing temperature was the most important factor in the effective removal of most soils. This was followed by the washing time, the detergent concentration, and finally the revolution speed. In this study it was found that superfluous amounts of detergent did not sufficiently increase the soil removal rate. Koreans who are used to washing with cold water should increase the wash time to launder more efficiently.

• Journal of ILASS-Korea
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• v.20 no.3
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• pp.149-155
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• 2015

With increasing of GDP, the registration number of passenger cars has exceeded 20 million last year in Korea. Especially, the registration number of the diesel engine vehicles has been increasing. However, the WHO(World Health Organization) IARC (International Agency for Research on Cancer) has reported that diesel engine exhaust gas is an one of HAPs, which has carcinogenic for human, and they have designated it to Group 1. To solve this problem, exhaust gas from diesel engines has to be controlled. Thus, it has been controlling by European regulatory standard in Korea. On the other hand, in order to meet the enhanced emission regulations, all manufacturing company applied $NO_x$ control device to vehicles such as EGR (Exhaust Gas Recirculation), SCR (Selective Catalytic Reduction) and so on. However, these devices (EGR, SCR) were operated by difference reaction mechanism respectively, and the composition of exhaust gas would be differenced from that of them. In this study, it was conducted to evaluate variety characteristics on changing of exhaust gas composition by each $NO_x$ control device, and the heavy duty diesel trucks were chosen as experimental vehicles. From the result, it revealed that vehicles (with EGR) were discharged higher THC as 52.5% than that of others (with SCR). However, it did not followed that trend, in the case of CO; it was discharged as 57.2% lower than that of others (with SCR). In the future, these data would be used to apply to efficient $NO_x$ control device for meeting to EURO 6.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.1
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• pp.26-33
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• 2007

The intake swirl motion, as one of dominant effects for an engine combustion. is very effective for turbulence enhancement during the compression process in the cylinder of 2-valve engine. Because the combustion flame speed is determined by the turbulence that is mainly generated from the mean flow of the charge air motion in intake port system. This paper describes the experimental results of swirl flow and combustion characteristics by using the oil spot method and back-scattering Laser Doppler velocimeter (LDV) in 2-valve single cylinder transparent LPG engine using the liquid phase LPG injection. For this. various intake port configurations were developed by using the flow box system and swirl ratios for different intake port configurations were determined by impulse swirl meter in a steady flow rig test. And the effects of intake swirl ratio on combustion characteristics in an LPG engine were analyzed with some analysis parameters that is swirl ratio. mean flow coefficient, swirl mean velocity fuel conversion efficiency. combustion duration and cyclic variations of indicated mean effective pressure(IMEP). As these research results, we found that the intake port configuration with swirl ratio of 2.0 that has a reasonable lean combustion stability is very suitable to an $11{\ell}$ heavy-duty LPG engine with liquid phase fuel injection system. It also has a better mean flow coefficient of 0.34 to develope a stable flame kernel and to produce high performance. This research expects to clarify major factor that effects on the design of intake port efficiently with the optimized swirl ratio for the heavy duty LPG engine.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.5
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• pp.22-33
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• 2000

Since the heavy-duty power manipulator generally has high ratio gear reducers at its joints, its dynamic characteristics is much slower than that of the master manipulator and it is likely to encounter the saturation in the input magnitude when it is used as the slave manipulator in telemanipulation systems. This paper proposes a force reflecting and compliant control scheme for the heavy-duty power telemanipulator. The main advantage of the proposed scheme is that it provides a precise position and compliant control performance for a telemanipulator with control input saturation. The stability of the proposed scheme is analyzed and a series of experiments shows its performance.