• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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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.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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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.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.10
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.353-362
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• 2019

Thermodynamic analysis of cascade refrigeration systems has attracted considerable research attention. On the other hand, a system evaluation based on thermodynamic analyses of the individual parts, including the evaporator, condenser, intercooler, expansion valve, etc., has received less attention. In this study, performance analysis was conducted on a cascade refrigeration system, which has an individual cooling and refrigeration evaporator, and equips the intercooler and air-cooled condenser in a series in a lower cycle. The thermo-fluid design was then performed on the major components of the system - upper condenser, lower condenser, cooling evaporator, refrigeration evaporator, intercooler, compressor, electronic expansion valve - of 15 kW refrigeration, and 8 kW cooling capacity using R-410A. A series of simulations were conducted on the designed system. The change in outdoor temperature from 26 C to 38 C resulted in the cooling capacity of the lower evaporator remaining approximately the same, whereas it decreased by 9% at the upper evaporator and by 63% at the intercooler. The COP decreased with increasing outdoor temperature. In addition, the COP of the cycle with the intercooler operation was higher that of the cycle without the intercooler operation. Furthermore, the increase in the upper condenser size by two fold increased the upper evaporator by 4%. On the other hand, the lower evaporator capacity remained the same. The COP of the upper cycle increased with increasing upper condenser size, whereas that of the lower cycle remained almost the same. When the size of the lower condenser was increased 2.8 fold, the intercooler capacity increased by 8%, whereas those of upper and the lower evaporator remained approximately the same. Furthermore, the COP of the lower cycle increased with an increase in the lower condenser. On the other hand, the change of the upper condenser was minimal.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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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.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.11a
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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)

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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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.

• Proceedings of the SAREK Conference
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• 2009.06a
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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.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.2
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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.