• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.203-208
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• 2008

The purpose of this study is to compare the different shapes of condenser of the direct contact heat transfer from the heat pipe condenser to the receiving water using CFD. The heat transfer from the working fluid of the heat pipe to receiving fluid flows through the manifolder is one of the important part in evacuated solar collector system. The retrenchment of the thermal resistance between the heat pipe and the manifolder could increase the thermal performances of the whole system. Recently, direct heat transfer from the heat pipe condenser wall to the receiving water was suggested and accompanied experiments were achieved. This experiment shows the better performances of the direct contact heat transfer analogically. Preceding calculations are carried out for the performance comparison: mesh dependence test, discretization method test and equation model test. with these preceding tests, 4 different shapes of condenser are compared and each case were set up for the same heat flux at the condenser wall. The calculation result shows that the efficiency of the extended surface condenser shape is 10% higher then the that of the others.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.983-988
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• 2017

This study describes the design and implementation of OMUX(Output Multiplexer) for Satellite Communication. The OMUX unit for SHF band consists of LPF(Low Pass Filter), manifolder and Channel Filter. Through the pre-simulation analysis of space environment, the possibility of the malfunction of equipment minimized and we designed a reliable OMUX through simulation for vibration analysis generated during the launch, and compared pre-simulation of main performance results to test results about main performances of OMUX after production.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.727-733
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• 2020

Recently, reciprocating cryogenic pumps are mainly developed for small-and-mid sized fuel supply systems. Centrifugal type pumps are not actively developed. Most cryogenic submerged pumps are imported. For transportation, cryogenic liquefied natural gas requires the liquid pump technology that can works in extreme evironments. In order to transport liquefied natural gas, it is necessary to apply pump technology. This is the fundamental research for developing the submerged pump technology applicable to the transportation and storage system equipment of cryogenic liquefied system. It tries to secure basic design materials through reverse-engineering in the cryogenic submerged pump development. Regarding materials, STS-304 and STS-431 which are stainless materials widely used in the cryogenic area are applied. Aluminum alloy is applied to impeller and upper manifolder and the pump rotates at the high speed of 6,000rpm.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.2
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• pp.81-87
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• 2009

Final purpose of this study was designed to develop the quality control(QC) sample for proficiency analytical testing of asbestos. This study consisted of two parts; first, development of manufacturing apparatus and sample preparing procedure for asbestos quality control(QC) sample: second, validation of the QC samples made by our developed method as asbestos proficiency analytical testing sample. The main results of the first part research are as followed We developed the apparatus for manufacturing the asbestos QC sample, consisted of filter hold, filter holder manifolder, vacuum system, and vacuum pump. The most proper filter of making the QC samples was a cellulose ester membrane filter with 25 mm diameter, pore size 0.8 um. And we presented the optimal procedure for preparing the asbestos QC sample by using the developed apparatus. We will verify the manufactured asbestos QC samples by this method, and present the validation results to confirm the reliability as a asbestos QC sample in next paper.