• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1139-1144
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• 2005

This study has been performed to investigate the thermal performance of variable conductance heat pipe (VCHP) with meshed wick. The length of condenser portion in a VCHP is varied by the expansion of inert gas with the operation temperature, and the heat transport capacity is thus varied with the operating temperature. In this study, numerical evaluation of the VCHP is made for the thermal performance of VCHP, based on the diffusion model of inert gas. Water is used as a working fluid and nitrogen as a control inert gas in the copper tube. As a result, the thermal performance of VCHP has been compared with that of constant conductance heat pipe (CCHP) according to the variation of operation temperature. Maximum heat transport capacity of VCHP is mainly presented for operation temperature and the variation of operation temperature is also presented for heat transfer rate of VCHP.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.165-172
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• 1999

Landfill gas has merely half heating value compared with liquified natural gas but can be greatly utilized as a commercial fuel. The authors have examined emission characteristics as well as measured burning velocity of LFG mixed gas which contains plenty of $CO_{2}$. With the viewpoint of fuel utilization, flame stability could be one of important characteristics of LFG. In this study, the comparison experiments are conducted between $CH_{4}$ and LFG for searching the region of flame stabilization based upon the flame blowout at maximum fuel stream velocity. As a result, it is found that stabilization region of LFG is not improved with that of $CH_{4}$ in non-swirl/or weak swirl jet diffusion flame. However, it is also known that flame stability is hardly affected by inert gas in the strong swirl with considering widened flame stabilization region of LFG rather than LNG.

• Journal of Powder Materials
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• v.9 no.6
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• pp.409-415
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• 2002

In this review the methods for production and processing of isolated or agglomerated nanoscale metal particles embedded in organic liquids (nanosuspensions) and polymer matrix composites are elucidated. Emphasis is laid on the techniques of inert gas condensation (IGC) and high pressure sputtering for obtaining highly porous metal powders ("nanopowder") as well as on vacuum evaporation on running liquids for obtaining nanosuspensions. Functional properties and post-processing are outlined in view of applications in the fields of electrically conductive adhesives and anti-microbially active materials for medical articles and consumer goods.mer goods.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.165-167
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• 2004

마찰교반접합(FSW, Friction Stir Welding)은 영국 TWI에 의해 1991년에 개발되어 특허가 출원된 후 90년대 중반부터 산업에 적용되었으며, 짧은 시간동안에 실용화가 이루어졌다. 이 기술이 적용되기 전, Al 합금의 접합은 MIG(Metal Inert Gas)나 TIG(Tungsgten Inert Gas)와 같은 접합이 주로 이용되어 왔으나, 이들 접합기술은 접합부의 표면문제, 변형, 결함 등으로 인하여 Al 합금의 구조물 적용에 큰 문제점이 야기되어왔다. (중략)

• Journal of Welding and Joining
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• v.20 no.5
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• pp.127-133
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• 2002

In this study, metal transfer characteristics in pulsed current metal inert gas (MIG) welding of aluminum was investigated. Based on the metal transfer characteristics from direct current electrode negative MIG welding, the one drop per one pulse(ODOP) condition was predicted and compared with experimental data. The results indicated that experimental pulse range for the ODOP condition is wider than that predicted from the DCEP MIG welding data. In addition, more stable metal trnasfer behavior was obtained at the higher end of the ODOP condition.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1466-1468
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• 2009

The preparation method of copper nanopowder by dry process for conductive ink was investigated. Inert gas condensation method was used to synthesize copper nanopowder. The produced powders was spherical and sized 10~100nm flowing the conditions. The results showed that input voltage and evaporation rate is critical variables for nano-sized copper powder.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.616-621
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• 2003

MIG or TIG welding has been the most popular welding process for joining aluminum alloy structures. However, porosity, hot crack and distortion were serious problems in inert gas fusion welding. Since FSW(Friction Stir Welding) was invented by TWI in 1991, it has been the powerful candidate for solving the problems of inert gas welding. In this paper, the principle and characteristics of FSW is introduced and its application to rolling stocks is presented to make basis for future development in production technology of aluminum rolling Stocks.

• Fire Science and Engineering
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• v.18 no.1
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• pp.7-12
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• 2004

For CFCs and Halons regulated by Montreal Protocol and their alternatives of HFC-23, HFC-125 HFC-227ea, HFC-236fa and the mixtures of inert gases of $Ar, N_2 and CO_2$, the thermodynamic properties of saturated pressure, density, enthalpy and viscosity were compared. In this study, the data from literature were expressed as a function of temperature. Thermodynamic properties of HFC compounds were similar to those of Halon-1301. Inert gas was mainly used as a mixture, but the physical properties of the inert gas does not have the favorable advantages over those of Halon-1301.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.2
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• pp.328-335
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• 2002

In this study, experiments were performed to investigate the characteristics of flame stabilization of the LFG mixing gas. LFG has merely half heating value compared with liquified natural gas but can be greatly utilized as a commercial fuel. In order to use LFG in practical combustors, Webbe Index and heating value of LFG mixing gas were adjusted by mixing LPG with LFG. The comparisons were conducted between CH$_4$and LFG mixing gas for searching the region of flame stabilization based upon the flame blowout at maximum fuel stream velocity. As a result, the flame stability of LFG mixing gas was not improved with that of CH$_4$in non-swirl and weak swirl diffusion flame. However, LFG mixing gas had wide flame stabilization region rather than CH$_4$with increasing ambient flow rate in strong swirl. It was also found that flame stability was affected by included quantity of inert gas such as CO$_2$in the weak swirl but by heating value of fuel in strong swirl.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1929-1934
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• 2022

Besides recent progresses in the physics-based modelling of fission gas and helium behaviour, the scarcity of experimental data concerning their combined behaviour (i.e., cocktail) hinders further model developments. For this reason, in this work, we propose a modelling methodology aimed at providing recommendations for accelerated experimental investigations. By exploring a wide range of annealing temperatures and cocktail compositions with a physics-based modelling approach we identify the most interesting conditions to be targeted by future experiments. To corroborate the recommendations arising from the proposed methodology, we include a sensitivity analysis quantifying the impact of the model parameters on fission gas and helium release, in conditions representative of high and low burnup.