• 한국자동차공학회논문집
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• 제15권2호
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• pp.87-94
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• 2007

It has been argued that the use of plastics can cause problems during design and manufacture owing to their low strength, relatively poor thermal conductivity and large thermal expansion. However, the advantages of plastics e.g., corrosion resistance, low cost, curtailment of weight, design flexibility etc., can compensate abundantly for the disadvantages. This study analyzes and compares the heat transfer performance characteristics of automotive compact oil cooler composed of plastic tube bundle with conventional metal oil cooler on the same core area basis as diameter, tube thickness, number of tube or tube arrangement varies. The performance analyses are accomplished by use of computational fluid dynamics program Fluent 6.2, which is verified and compared with the results of performance tests. The result of analyses is coincided with that of experiments. Flow pattern at air side according to tube arrangement is dominant factor which affects heat dissipation in case of similar total heat transfer surface area.

• 한국자동차공학회논문집
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• 제23권6호
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• pp.608-614
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• 2015

Nitrogen oxide(NOx) emission reductions are required to meet the strict emission regulations for environmental protection. Most of the Exhaust Gas Recirculation(EGR) system applied to a diesel engine can relatively decrease the NOx at a low cost, but it has a disadvantage in that the PM generation is promoted due to the hot intake air temperature. Thus, high heat exchange efficiency of the EGR cooler is required for an effective removal of NOx. In this study, heat exchange efficiency for various types of heat exchangers used in EGR cooler was measured under same conditions, and determined best heat exchange performance shape depending on type of heat exchanger.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.623-628
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• 2009

Desiccant based air conditioning system offers a promising alternative to conventional one using vapour compression refrigeration for energy saving and greenhouse gas reduction. It is a heat driven cycle which has high potential for the use of low grade heat source such as the waste heat from the cogeneration plant or the solar thermal energy. In this study, the cooling performance of a desiccant cooling system incorporating a regenerative evaporative cooler was characterized in various operation conditions through numerical simulation. The cooling capacity and COP were evaluated at various outdoor conditions, regeneration temperatures, and supply flow rates. Based on the performance characteristics, the optimal control scheme was discussed to minimize the cooling cost at part load condition.

• 한국자동차공학회논문집
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• 제13권2호
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• pp.10-15
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• 2005

This study was initiated to evaluate the cooling performance of CAC (charged air cooler) and radiator in the engine room of a mini bus. So we had firstly to predict the mass flow rate coming from radiator grille and front bum per opening using computational fluid dynamics (CFD) simulation based on 3D configuration. And simulations were carried out for different cooling module layout and bum per opening hole size on sam e vehicle operating condition. Simulation results show that CAC cooling performance at reverse protecting plate-applying model was much efficient than that of the bum per opening hole size-increasing model in IMTD point of view. Part of the CFD simulation results was com pared to with experimental data. It was confirm ed that the CFD approach using STAR-CD based on pursuing no-com promise solution could provide design engineers with useful design information in the early design stage of vehicle development.

• 설비공학논문집
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• 제16권8호
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• pp.741-747
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• 2004

The purpose of this study was to develop a cooler/heater using a thermoelectric module combined with a parallel flow type oscillating heat pipe with R-142b as a work ing fluid. The experiment was performed for 16 thermoelectric modules (6 A/15 V, size: 40${\times}$40${\times}$4 mm), varying design parameters of the heat pipe (inclination angle, working fluid charging ratio, etc) . Experimental results indicate that the optimum charging ratio and the inclination angle of the parallel flow type oscillating heat pipe were 30% by volume and 30%, respectively. The maximum cooler/heater capacity were 479W (COP : 0.47) and 630W (COP : 0.9), respectively.

• 설비공학논문집
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• 제3권4호
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• pp.231-240
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• 1991

A design method has been developed for a Stirling engine with a tubular heater and cooler and a screen type regenerator. This paper provides a design procedure to determine the thermodynamic states and the geometric configurations of the Stirling engine for residential heat pumps. The major design is concerned with the working spaces, i.e. compression and expansion spaces and the heat exchangers such as the heater, the cooler and the regenerator. The Schmidt analysis has been employed to obtain the mass flow rates and heat transfer requirements of the system. The performance analysis of a model Stirling engine was performed by Martini-Weiss program to prove the validity of this design method. The results obtained indicate that this design method is valid for the Stirling engine conceptual design and performance analysis.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권4호
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• pp.217-224
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• 2005

The purpose of this study was to develop a cooler/heater using a thermoelectric module combined with a parallel flow type pulsating heat pipe with R-142b as a working fluid. The experiment was performed for 16 thermoelectric modules (6A/15V, size: $40\times40\times4mm$), varying design parameters of the heat pipe (inclination angle, working fluid charging ratio, etc.). Experimental results indicate that the optimum charging ratio and the inclination angle of the parallel flow type pulsating heat pipe were $30\%$ by volume and $30^{\circ}$, respectively. The maximum cooler/heater capacity were 479 W (COP: 0.47) and 630 W (COP: 0.9), respectively.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 동계학술대회 논문집
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• pp.76-76
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• 2004

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.95-95
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.28-28
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• 2004