• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.167-168
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• 2010

Non coating type Low melting yarn(L/M PET) not to use the polyurethane resin causing some problems was knitting and evaluated its dyeing characteristics, heat setting properties and flame-retardant properties without flame retardant agent or flame retardant fabric. In order to investigate the dyeing property of fabric of L/M PET, the dyeing of L/M PET was experimented at each different dyeing temperature. Higher exhaustion yield was achieved at lower temperature of L/M PET compared to regular PET. According to result of the study for the heat setting properties of L/M fiber, the K/S value of dyed L/M fiber increased as much as the heat setting temperature did. The experiment for the light fastness reached similar result to dyed PET. However washing fastness in L/M fiber showed lower grade compared with regular PET. flame-retardant efficiency of L/M PET without flame retardant agent or flame retardant fabric measured by $45^{\circ}$ burn test and Contact burn test. The flame?retardant performance of the sample was carried out according to the Korea Fire-fighting Standard.[KOFEIS 1001].

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.328-340
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• 1991

The combustion process in the combustion chamber has been investigated by taking pressure, temperature, chemical equilibrium and the shape of flame. To predict temperature of a flame in a combustion chamber is one of very important problems in the field of combustion and the temperature is a important factor of ignition and counteraction to inflammation. In this paper, the flame temperature was determined by the method of the Rayleigh scattering of Ar-Ion Laser (514.5nm). The Rayleigh scattering has been got considerably attention because of its strong cattering intensity. As a result, it is shown that I can measure the shape of flame by schlieren photography and that I can get the flame temperature variation in constant volume combustion chamber by Laser Rayleigh Scattering.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.6
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• pp.633-640
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• 2011

In this study, the stabilization of an edge flame and the intensity variation of a diffusion branch were investigated using a multi-slot combustor under conditions of high temperature and small fuel-concentration gradient (FCG). The combustor consists of three narrow channels: a quartz channel and two side-heating combustors. For the accuracy of this experimental study, quantitative analysis was carried out for each boundary condition. Stable edge flames could be observed under high-temperature conditions by controlling the FCG and fuel dilution ratio. Moreover, it was found that the intensity of the diffusion flame was increased by increasing the temperature of the mixture. On the contrary, the intensity of the diffusion flame was decreased by increasing the dilution ratio. It was also found that a propane flame is more sensitively affected by these experimental parameters than a methane flame.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.937-942
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• 2000

The characteristics of spray combustion and dropsize of spray through twin-fluid atomizer was experimentally investigated. The distribution of flame temperature have an effect on the generation of NOx. To investigate there effects, flame temperature with different spray shape was observed. The spray shape was varied by various bluff-bodys. Mean temperature were measured by thermocouple respectively, and NOx concentration was measure by NOx analyser. Distribution of droplet sizes were measured by PMAS. The result showed that the flame with wide distribution has lower temperature and lower NOx emission compared with narrow.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.9 s.252
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• pp.891-897
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• 2006

The SRS method is applied to a turbulent flame with radiation/turbulence interaction to invert the temperature and concentration profile. The flame is conditioned as optically thin per each fluctuation length and the flame spectral intensity is measured for inversion. From inversion result, we find that SRS can successfully invert the coupled temperature/concentration fluctuation amplitudes. For two cases of experiments, inverted values are within approximately 1% over the full range of fluctuation amplitude. However, SRS cannot find the detailed local fluctuation parameters such as pattern and phase, etc. as far as they do not affect the resulting radiation intensity. Important available parameters are the mean temperature and the temperature fluctuation amplitude. The radiation/turbulence interaction effect is verified to play an important role in the radiation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.2
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• pp.213-223
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• 1997

Premixed flame is better than diffusion flame to accomplish a high loading combustion. Since the turbulent characteristics of unburned mixture has a great influence on the flame structure, it is general that many researchers realize a high loading combustion with strengthening turbulent intensity of unburned mixture. Because turbulent premixed flame reacts efficiently on the condition of distributed reaction region, we made high turbulent premixed flame in the doubled impingement field. We investigated turbulent characteristics of unburned mixture with increasing shear force and visualized flames with direct and Schlieren photographs. And the combustion characteristics of flame was elucidated by instantaneous temperature measurement with a thermocouple, by ion currents with a micro electrostatic probe, by radical luminescence intensity and local equivalence ratio. Extremely strong turbulent of small scale is generated by impingement of mixture, and turbulent intensity of unburned mixture increased with the mean velocity. As a result of direct photographs, visible region of flame became longer due to increasing central direction flux. But as strengthed turbulent intensity, visible region of flame turned to shorter and reaction occurred efficiently. As strengthened turbulent intensity of mixture with increasing flux of central direction, maximum fluctuating temperature region moved to radial direction and fluctuation of temperature became lower. The reason is influx of central direction which caused flame zone to move toward radial direction, to maintain flame zone stable and to make flame scale smaller.

• Journal of Biosystems Engineering
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• v.29 no.1
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• pp.45-52
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• 2004

The chestnut is a well-blown and important forest product in Korea. The annual production of chestnut is about 95,000 tons and its cultivating area is 80,000 ha. However, the peeling process of outer and inner skins of chestnut is very difficult due to hardness and adhesiveness of chestnut skin. The purpose of this study was to develop a prediction model for flame peeling characteristics of domestic chestnuts, and to evaluate an optimization model to determine the operation conditions of the chestnut flame peeling system. The results of this study were summarized as follows. It was found that the flame peeling characteristics of domestic chestnuts were by the flame temperature, and the flame time. The peeling ratio and the heating depth were increased as the flame temperature and the flame time were increased. The peeling ratio and the heating depth were increased linearly when those were less than 85 % and 2 mm respectively. As the hardness of chestnut shell was decreased, the peeling ratio was increased. A simulation model was developed to predict the peeling ratio and the heating depth based on the hardness of the chestnut shell, the flame temperature, and the flame time of the peeling system. The model was evaluated by comparing the measurement and the prediction of the peeling ratios and heating depths, and showed the good relationship.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.5
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• pp.687-694
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• 1999

An experimental study was carried out in two laboratory-scale reactors to investigate the effect of heating rate on the behavior of flame front in a pulverized coal flame. Each. reactors had different heating mechanisms. For reactor A losing large heat through transparent quartz wall. pulverized coal particles were ignited by secondary air of 1050K. Flame front could be visualized through the transparent wall. Reactor B was insulated with castable refractory to minimize the heat loss through the reactor wall and accompanied with secondary air of 573K. Flame front was estimated from the gas temperature and species concentration measured using R-type thermocouple(Pt-Pt/Rh 13%) and gas chromatograph at various coal-air ratios and swirl intensities. The flame front position was closely related with the magnitude of heating rate. The heating rate for lifted flame was of the order of $10^4$ to $10^5K/s$ and for coal Ignition at least over $10^4K/s$. The heating mechanism had little impact on the extinction limits. The weak swirl number of 0.68 forced the flame front to move toward the upstream by the rapid mixing of coal and air. The primary/secondary momentum ratio was an inappropriate variable to distinct the liftoff of flame.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.3
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• pp.1028-1039
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• 1996

This study was focused on the examination of the flame structure and the combustion characteristics of diffusion flame which was formed the turbulent shear flow of a double coaxial air jet system. The shear flow was formed by the difference velocity of surrounding air jet(U$\_$s/) and center air jet (U$\_$c/). So experimental condition was divided S-type flame (.lambda. > 1) and C-type flame (.lambda. < 1) by velocity ratio .lambda. (=U$\_$s//U$\_$c/). For examination of the flame structure and the combustion characteristics in diffusion flame, coherent structure was observed in flame by schlieren photograph method. We measured fluctuating temperature and ion current simultaneously and accomplished the statistical analysis of its. According to schlieren photograph, the flame was stabilized in the rim of the direction of lower velocity air jet, coherent eddy was produced and developed by higher velocity air jet. The statistical data of fluctuating temperature and ion current was indicated that reaction was dominated by higher velocity air jet. The mixing state of burnt gas and non-burnt gas was distributed the wide area at Z = 100 mm of C-type flame.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.3
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• pp.1050-1060
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• 1996

Recently, attention has been paid to the flame diagnostic by noncontact methods which dose not deform the flame shape. One of them is a method which is using the radical luminous intensity. Generally, this diagnostic method using radical luminous has been investigated its reliability by applying to laminar flame. This study, however, investigated each radical luminous signals through stocastical analysis like auto-correlation, cross-correlation, phase and coherence which were acquired from measuring radical luminous intensity of OH, CH, $O_{2}$, radicals in turbulent diffusion flame. To compare radical luminous intensity in flame with temperature, ion current and concentration , radious distribution of each properties was investigated and considered. In radical luminous intensity, correlation in the reaction zone of flame was higher than in correlation in combusted gas zone. And radious distribution of radical luminous intensity was corresponded with radious distribution of temperature, ion current and concentration. The result of the study confirms that a radical luminous flame diagnosis is possible in the turbulent diffusion flame.