• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.552-553
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• 2012

현재의 발전소 내부에 가동 중인 열교환기 배관 라인의 Clinker Monitoring System은 초고온의 열교환기 내부의 벽면 및 배관라인의 클링커 상태를 감시하는 시스템을 요구하고 있다. 이러한 열교환기 내부의 상태를 감시하기 위하여 초고온에 견딜 수 있고 회전이 가능한 장치를 열교환기 내부에 투입하여 회전 가능한 장치를 통하여 원격으로 영상을 전송하도록 하여 클링커 상태를 영상으로 모니터링 하여 열교환기 내부의 상태를 감시 관찰 분석할 수 있는 시스템을 구성하였다. 본 논문에서는 발전설비의 열교환기 내부의 클링커 상태를 모니터링 할 수 있도록 회전 가능한 렌즈 튜브와 보호용 냉각 시스템을 추가된 통합 모니터링 시스템을 제기하고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.587-592
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• 2008

In order to investigate the performance of an internal heat exchanger for $CO_2$ refrigerant system, the experiment was performed. Four kinds of internal heat exchangers(IHX) were used. The effects on the IHX length, the number of tube, the operating condition and the type of IHX were investigated. With increasing of the IHX length, the capacity and efficiency increased. The pressure drop of the low-side was larger compared with that of the high-side. As the temperature of the gas cooler increased, the capacity and efficiency increased linearly. The operation condition of evaporator was suggested as two phase region rather than superheat region. The capacity and efficiency of the micro-channel was larger about 90% and 75% than those of the tube. But the pressure drop of the micro-channel was more larger, compared with that of the tube.

• Journal of Power System Engineering
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• v.13 no.5
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• pp.5-10
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• 2009

본 연구에서는 판형열교환기를 적용한 청수제조장치의 성능에 대하여 연구를 수행하였다. 판형열교환기는 자체의 높은 열전달 성능과 컴펙트한 장점으로 하여 산업에서 점차 널리 사용되고 있다. 또한 사용, 유지보수가 다른 종류의 열교환기에 비하여 편리하여 유연성 있게 사용할 수 있다. 본 실험에서는 세브론 각도가 60도인 전열판을 사용하였으며 이젝터의 작동으로 열교환기를 장착하고 있는 탱크내부에 진공압력을 유지함으로서 내부유체가 $51^{\circ}C{\sim}57^{\circ}C$에서 증발현상이 발생하는 것을 확인하였다. 또한 수치해석적 방법을 통하여 복잡하며 좁은 세브론전열판으로 이루어진 유로내의 유동특성을 파악할 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.69-73
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• 2013

Internal heat exchanger (IHX) apparatus using the temperature difference between high and low pressure lines in vehicle air conditioning system is a good method to enhance the cooling performance. In this study, we designed various double-pipe internal heat exchangers which have inner fins between the internal pipe and external pipe. We also measured the performance characteristic (pressure drop, cooling capacity, compressor work and coefficient of performance (COP)) of the modified internal heat exchangers that had the change of the fin height and the inside shape of the internal pipe. This experimental results indicated that the liner and serration type internal heat exchanger was the best cooling performance. In addition, the air conditioning system with the liner and serration type internal heat exchanger showed the improved performances of about 6.4% and 9.2%, respectively, for the cooling capacity and COP.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.8
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• pp.1123-1128
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• 2009

In this paper, the cycle performance characteristics of a cascade refrigeration system with internal heat exchanger using natural refrigerants is presented to offer the basic design data for the operating parameters of the system. This system considered in this study is consisted of a high temperature cycle using a carbon dioxide(R744) and low temperature cycle using refrigerants such as R290, R1270, R600a and Ethane. The main results were summarized as follows : The COP of the cascade refrigeration system of R600a with internal heat exchanger is the highest grade in low temperature cycle using refrigerants such as R290, R1270, R600a and Ethane. The COP of the cascade refrigeration system with internal heat exchanger only in high temperature cycle is the highest value among three type cycle, such as only low temperature cycle, only high temperature cycle and all the cycle.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.6
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• pp.237-243
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• 2020

In this study, a silane-based coating was applied to improve corrosion resistance and thermal efficiency performance of a brazed plate heat exchanger (BPHE) composed of stainless plate and copper (Cu) brazing. Although the selected coating material was applied to the BPHE by evaluating the corrosion and contact angle according to the coating material, the result of the heat transfer performance evaluation showed that the thermal efficiency was lower than that of the uncoated BPHE. It was analyzed that the adhesion of the coating agent to the flow path inside the BPHE and the residual coating agent on the surface acted as heat resistance, preventing heat transfer. This is due to the structural characteristics of the BPHE in which a fine flow path exists inside, and it is believed that manufacturing after coating the surface of the flow path in advance in the manufacturing process of the BPHE can improve heat transfer performance.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.32.2-32.2
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• 2005

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1027-1029
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• 2015

Heat exchange ventilation facility is using for heating the inflow outside-air with warm outflow inside-air. Energy cost is saved and respiratory disease caused by temperature difference of air is prevented. In this paper, system for remote control and monitoring of heat exchange ventilation facility is developed. This system is applied in chicken breeding farm, and verification test of performance such as temperature and humidity control and monitoring is conducted. From verification test, temperature control error is measured as under 2degrees around the chicken breeding farm.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.427-430
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• 2008

This study considered the heat exchanger of bleed air from engine. The computional fluid analysis was performed considering the external flow and internal flow on heat exchanger. Using the CFD results, the external configuration and internal flow path of heat exchanger were designed. And also the performance test is conducted and the results of tests were compared with the analysis resutls.

• Journal of the Korean Institute of Gas
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• v.14 no.5
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• pp.1-6
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• 2010

In this work, a numerical investigation is performed for the combustion chamber of domestic gas boiler with 1-stage and 2-stage heat exchangers. The fluid flow and heat transfer performance is simulated with a structure change of heat exchanger. The numerical solution shows that the heat transfer of the 2-stage heat exchanger is about 24% higher than that of the 1-stage heat exchanger, while the pressure loss of the 2-stage heat exchanger increases. The temperature of combustion chamber with 2-stage heat exchanger is lower than that of 1-stage. This effect reduces thermal NOx with decrease of high temperature staying time of the combustion gas.