• 한국기계가공학회지
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• 제13권5호
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• pp.43-49
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• 2014

This study was carried out to improve the design of an intercooler for a small marine diesel engine. Diesel engines for small marine ships have mainly been developed by changing the structure of the vehicle engine. Sea water was most commonly used in the intercooler of small marine diesel engines to cool the hot air compressed by the turbocharger. In this study, the intercooler is modeled and simulated using STAR-CCM+ in order to find optimal data for the design of an intercooler. In the results, the temperature differences between the data from a numerical analysis and experimental data were $0.38^{\circ}C$ in the hot air outlet and $3.63^{\circ}C$ in the cooling water outlet. Therefore, it was confirmed that both analysis and experimental results need to be considered when designing an intercooler. A closer degree of similarity in the two datasets can improve the confidence in the design of these intercoolers.

• 한국자동차공학회논문집
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• 제17권2호
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• pp.171-179
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• 2009

An object of this study is to confirm application characteristics of the vortex tube apparatus for substitution of the intercooler in a common-rail diesel engine. The turbo pressure, the intake air mass flow rate and the charging air cooling ratio of the intercooler were measured in an experimental engine. The vortex tube apparatus was made after confirmation of the geometric phenomena in fundamental experiments. The vortex tube designed with fundamental data was applied to a conventional common-rail diesel engine instead of the intercooler. Its application characteristics, engine performances and emissions were investigated. From this experimental results, we suggested the vortex tube can be applied to a conventional common-rail diesel engine throughout extra complement. We can also expect the higher cooling effect, if we consider the application of the vortex tube in supercharging diesel engine without the intercooler.

• 한국자동차공학회논문집
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• 제16권3호
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• pp.172-178
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• 2008

An object of this study is to confirm performance characteristics of the vortex tube apparatus for substitution of the intercooler in a common-rail diesel engine. The turbo pressure, the intake air flow rate and the ${\Delta}T_c$ decrease ratio of the intercooler were measured in a experimental engine. The vortex tube apparatus was made after confirmation of the geometric phenomena in fundamental experiments. To investigate energy separation characteristics of the vortex tube, the measured turbo pressure was applied to the vortex tube inlet and the ${\Delta}T_c$ decrease ratio was compared with one of the intercooler in the cold air mass flow ratio similar to the intake air flow rate of the experimental engine. From the results, we found that the energy separation ratio is increased according to of the inlet pressure and the ${\Delta}T_c$ decrease ratio of the vortex tube apparatus is higher than one of the intercooler at low engine speed and engine load of medium and low.

• 설비공학논문집
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• 제18권10호
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• pp.835-841
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• 2006

A $CO_2$ system using the two-stage compression cycle was tested by varying $1^{st}-2^{nd}$ compressor frequencies in the cooling mode. To improve the cooling performance of the two-stage compression $CO_2$ cycle, the following cycle options were applied: a basic cycle, a cycle with an intercooler, a cycle with an IHX (internal heat exchanger), and a cycle with an intercooler and IHX. The cycle with the intercooler-IHX showed the highest cooling capacity improvement among the cycle options at all compressor frequencies. The cycle with the intercooler, the cycle with the IHX, and the cycle with the intercooler-IHX improved the cooling COP by 7, 12, and 15%, respectively, over the basic $CO_2$ cycle when the compressor frequencies for the first and second compressors were 50 Hz and 30 Hz, respectively. In addition, the applications of the selected cycle options enhanced system reliability.

• 한국산학기술학회논문지
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• 제20권7호
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• pp.353-362
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• 2019

그간 캐스케이드 냉동 시스템에 대해서 열역학적 해석은 다수 수행되었으나 증발기, 응축기, 인터쿨러 등 부품 해석을 통한 시스템 평가는 미진한 상태이다. 본 연구에서는 냉방 및 냉동 열교환기가 별도로 장착되어 있고 하부 사이클에 공랭식 응축기와 인터쿨러가 직렬로 연결되어 있는 캐스케이드 냉동 사이클에 대해 성능 해석을 수행하였다. 우선 증발기, 응축기, 인터쿨러 등 요소부품에 대해 모델링을 수행하고 R-410A를 사용하는 냉방 능력 8 kW, 냉동 능력 15 kW의 캐스케이드 냉동 사이클의 요소 부품의 - 상부 응축기, 하부 응축기, 냉방 증발기, 냉동 증발기, 인터쿨러, 압축기, 전자팽창변 - 설계를 수행하였다. 설계 사양에 대하여 외기 온도를 $26^{\circ}C$에서 $38^{\circ}C$로 변화시키며 해석을 수행한 결과 냉각 열량은 하부 증발기에서는 거의 일정하고 상부 증발기에서는 9% 감소, 인터쿨러에서는 63% 증가하였다. 한편 COP는 외기 온도의 증가에 따라 감소하였다. 인터쿨러가 작동하지 않는 사이클 대비 인터쿨러 사이클이 COP 측면에서 우위를 보였다. 또한 상부 응축기의 크기를 당초 설계치의 2배 증가시키면 하부 증발기 열량은 변함이 없는 반면 상부 증발기 열량은 4% 증가하였다. 한편 상부 응축기의 크기 증가에 따라 상부 사이클의 COP는 증가하는 반면 하부 사이클의 COP는 큰 변화가 없다. 또한 하부 응축기 크기를 2.8배 증가시키면 상하부 증발기의 열량 변화는 거의 없고 인터쿨러의 열량만이 8% 감소하였다. 아울러 하부 사이클의 COP는 응축기의 크기가 증가함에 따라 다소 증가하였으나 상부 사이클의 경우는 그 변화가 미미하였다.

• 한국기계가공학회지
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• 제12권6호
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• pp.125-131
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• 2013

This study was carried out to develop a diesel engine for marine propulsion. This marine diesel engine was developed based on a 500Ps vehicle diesel engine. Many main parts, such as the intercooler, radiator, and engine controller were designed for the marine diesel engine. The intercooler was designed to be of sea water cooling type; inlet air is cooled by sea water. Engine coolant is cooled by sea water in the radiator too. The water cooling heat exchanger has high cooling performance. In the cooling system, consists of the intercooler and the radiator, the sea water passes through the intercooler and then the radiator, in sequence. This process is very effective compared to the reverse method in which sea water passes through the radiator and then the intercooler, in sequence. The control performance of the engine controller and the fuel injection rate were improved using an engine speed controller. This system was tested on an engine dynamometer and an exhaust gas analyzer using the marine diesel engine test method. Test results show that the 500Ps marine diesel engine satisfied the IMO NOx regulations; Tier II.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2000년도 제15회 학술강연회논문초록집
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• pp.40-40
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• 2000

터보기기에서 압축기를 통과한 공기는 압력이 증가하지만 온도가 따라서 증가하여 여러 단을 거쳐 높은 압축 비를 요구할 경우에는 압축기의 단단 사이에 열교환기 (intercooler)를 장착하여 다음 단으로 유입되는 공기의 온도를 낮추고 공기 중에 섞여있는 수분을 제거함으로써 터보기기의 전체적인 효율을 상당히 증가시킬 수 있다.(중략)

• 한국생산제조학회지
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• 제9권4호
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• pp.123-130
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• 2000

Studies on the turbocharger itself or various aspects generated from turbocharged engine have been made on the performance for the natural aspirated engine equipped with the turbocharger and the intercooler. In this study, the performance prediction program based on turbocharger theory is developed for simulation which may reduced the cost and the trial -and-error time. The program is verified with the experimental results for 11, 000 cc diesel engine with the turbocharger and the intercooler . Also, various factors which are invisible in experiment are predicted using this program.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.556-560
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• 2009

In this paper, two different types of natural gas liquefaction process are simulated and designed for secure a competitiveness in the industry of natural gas liquefaction plant. These processes are based on basic cascade process, and one of these is improved with two staged intercooler and the other is modified two staged intercooler. These processes are compared characteristics of performance with basic process. COP of cascade process with two staged intercooler and modified two staged intercooler showed about 13.74% and 21.64% higher than basic process, and yield efficiency of modified process improved comparing with the basic process by 25.93% lower specific power, respectively.

• 한국자동차공학회논문집
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• 제12권2호
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• pp.91-100
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• 2004

Plate heat exchangers (PHE) have been widely used in different industrial applications, because of high heat transfer efficiency per unit volume. Basic study is performed for PHE to the application of intercooler in automobile. In order to understand the flow phenomena in the plate heat exchanger, a channel which was formed by the upper and lower plate in single plate was considered as calculation domains. Because chevrons attached on the upper plate are brazed with chevrons attached on the lower plate, the flow channel has very complex configuration. This complex geometry was analyzed by Fluent. In order to validate this methodology the proper experimental and theoretical data are collected and compared with numerical results. Finally, due to the lack of experimental values for PHE to the application of intercooler, various chevron angles and air velocities at inlet were tested in terms of physical phenomena. From this point of view, results of velocity vector, path lines, static pressure, heat flux, heat transfer coefficient, and Nusselt number are physically reasonable and accepted for the solutions. From these results, the correlations for pressure drop and Nusselt number with respect to chevron angle and Reynolds number in specific PHE are obtained for the design purpose. Thus, the methodology of the flow analysis in the full geometry of the channel was established for the predictions of performance in plate heat exchanger.