• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.63-68
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• 2007

An experimental study was carried out to investigate gasification process of wood sawdust in the 1-dimensional downdraft fixed bed gasifier. The preheated air which was used oxidizer and steam were used as a gasifying agent. The downdraft fixed bed gasifier obtains more amount of hydrogen and methane by increasing residence time of supplied air. The operating parameters, the supplied air temperature and steam were used. The oxidizer temperature was varied from 500K to 620K and vapor was added. The gasification process was monitored by measuring temperature at three position near the biomass using R-type thermocouples and the syngas composition was analyzed by gas chromatograph. We get the sample gas at the end of gasifier and it was eonugh time to finishing the chemical reaction. Finally, the amount of hydrogen and methane were increased widely as increasing the oxidizer temperature and adding steam.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.67-73
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• 2010

The temperature distribution of diesel particulate filter with five partitioned electric heaters is numerically analyzed to investigate the condition of regenerating ceramic filter. The commercial code STAR-$CCM+^{(R)}$ is utilized to simulate multi-dimensional steady hot air flow in DPF. In order to verify the computational results, thermocouples are used to measure the temperature distribution in DPF. Computational results agree well with experimental ones. The results show that the maximum temperature in DPF is lowered as the mass flow rate of exhaust gas increases, which means that the more power in heater will be necessary as the engine speed increases. Compared with heater placed at center, heater at circumference has the higher maximum temperature in DPF. The maldistribution of flow field in front of heater has the main influence on the temperature distribution in DPF.

• Journal of Fisheries and Marine Sciences Education
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• v.19 no.3
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• pp.383-389
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• 2007

To evaluate the performance of heat exchanger with rotating porous plates, the experimental investigation was carried out under various conditions. With an equal interval of 18 mm inside the heat exchanger, the rotating porous plates are mounted. The hot and cold airs enter at opposite ends of heat exchanger and exchange heat each other. In order to measure the temperature distribution of the hot air side inside heat exchanger, the thermocouples are inserted between the plates. The first location of thermocouple is 10 mm downstream from the inlet of heat exchanger, and succeeding ten locations are aligned at an equal interval of 18 mm. As a result of the measurement, the temperature distribution inside heat exchanger was constant as the hot air temperature of inlet is low. It was found that the heat transfer rate does not depend on the variation of RPM at the lower temperature of inlet. The heat transfer rate at the higher temperature of inlet increased a little with the increase in RPM.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.1
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• pp.102-111
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• 2008

This paper describes the basic model and simulation results of thermal battery. Voltage and thermal analysis is a critical part of thermal-battery design because of the need to maintain the inner temperature above the electrolyte melting point. Traditionally, battery design has depended on an empirical approach, in which prototype batteries are outfitted with thermocouples and the design of subsequent batteries is refined accordingly. We have developed the basic model that allows the design engineer to configure or modify a battery, quickly conduct a thermal analysis, and efficiently review the results. Based on performance tests, the thermal-battery model was established and the effect of design parameters on battery performance was analyzed.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.187-192
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• 1998

Recent construction method in mass concrete structures would depend on the control of hydration heats and thermal stresses by using the low heat cement, optimized block size and a lift height, or both. This experimental study aims at the possibility of thermal cracks according to the different types of cementations material and at the investigation of these effects. Four different types of cements are applied to the mock-up test and are evaluated in terms of temperature rises and thermal stresses with the use of thermocouples, strain gauges and effective stress gauges. As a result of this study, it was found that stresses measured from effective stress gauges agree well with ones form strain gauges, and the trend of stress occurrence can be well evaluated from theoretical analysis.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.173-177
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• 1995

Thermal cracks ard occured when thermal stress due to the hydration of cement exceeds the tensile strength of concrete. Since cracking causes poor durability of concrete, the effect of thermal cracking should be included for the desing and construction of massive concrete structures. In this study, an experiments are performed for the investigation of time dependent temperature and thermal stress of massive concrete structure at early ages. In order to measure temperatures and thermal stresses, concrete stress meter, embedded strain meter, non-stress meter, and thermocouples are used. Based on the analyses of measured thermal stress data, measured values by concrete stress meter are more reliable than those by embedded strain meter and non-stress meter, And measured values by concrete stress meter are compared with the calculated values by FEM program developed by DICT (DWTS2D). Calculated values by DWTS2D show good agreement with measured values.

• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.463-473
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• 2015

Three full-scale instrumented test slabs were constructed and tested using a heavy vehicle simulator (HVS) to evaluate the structural behavior of internally cured concrete (ICC) for use in pavements under Florida condition. Three mix designs selected from a previous laboratory testing program include the standard mixture with 0.40 water-cement ratio, the ICC with 0.32 water-cement ratio, and the ICC mixture with 0.40 water-cement ratio. Concrete samples were prepared and laboratory tests were performed to measure strength, elastic modulus, coefficient of thermal expansion and shrinkage properties. The environmental responses were measured using strain gages, thermocouples, and linear variable differential transformers instrumented in full-scale concrete slabs. A 3-D finite element model was developed and calibrated using strain data measured from the full-scale tests using the HVS. The results indicate that the ICC slabs were less susceptible to the change of environmental conditions and appear to have better potential performance based on the critical stress analysis.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.487-488
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• 2006

In these days, demand of a LCD monitor is remarkably increasing with development of the LCD technology. However, there are thermal problems for improvement of efficiency for the LCD monitor. Thus, this research analyzed thermal problems such as convection and conduction heat transfer characteristics in the LCD monitor using an infrared (IR) camera. Also, the results of the outer side of the front LCD panel using the IR camera have been compared with the results of the inner side of the front panel using T-type thermocouples. The equations have been derived for the temperature distribution of the inner side of the front LCD panel by a multiple regression method including variables for ambient temperature, humidity and temperature differences between the front and back panels of the LCD monitor.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2386-2395
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• 1994

An experimental study on heat transfer and flow in compression molding of clss-B and A SMC(Sheet Molding Compounds) in a flat plate and a cross-sectional T-shape was carried out. The temperature was measured with thermocouples at two locations in the 4 layered SMC charge and pressure was measured at the center of the top mold during compression molding. Three different mold speeds, 15, 45, 50 mm/min and two different mold temperature, $130^{\circ}C{\;}and{\;}150^{\circ}C$ were used for compression molding experiments. Experiments with different colored SMC layers were used to study flow patterns at various compression stages. In oder to predict the pressure and load in SMC compression molding, slab method was used. The predicted values of pressure and load from the slab analysis were compared well with the measured data.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.9-15
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• 2001

In the case of a crack propagation, a portion of the work of inelastic deformation near the crack tip is dissipated as heat. In order to understand the thermal effect on fracture toughness, tensile test was carried out using thermocouples to monitor the variation of temperature with SA516 Gr70. The experimental results show that the temperature of specimen was increased $3.6^{\circ}C$ at static load condition. And the thermal effect was investigated connected with the steady-state stress in the vicinity of a crack propagation in the elastic-plastic C-T specimen theoretically. And fracture toughness, the energy to make crack surfaces, presented correctively. The fracture toughness with considering heat at the blunting of the crack tip ws lower about 19.3% than that of ignoring heat. So, it is resonable to apply the fracture toughness with considering thermal energy and it would be good explanation for constraint effect depending on the configuration in the presence of excessive plasticity.