• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.543-544
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• 2008

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.157-158
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• 2009

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.521-522
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• 2007

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.135-135
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• 2005

• 대한기계학회논문집B
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• 제26권8호
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• pp.1115-1122
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• 2002

The present experiment investigates the effects of pore density f of aluminum foam heat sinks, the jet-to-jet spacing X and the nozzle plate-to-target surface spacing H of 3$\times$3 square impinging arrays on the averaged Nusselt number. The performance of the aluminum foam heat sinks and the rectangular plate heat sink is evaluated in terms of the enhancement factor. /equation omitted/. The multiple impinging jet with X/d=4.0 displays higher Nusselt numbers than single impinging jet for 12.0$\leq$H/d$\leq$20.0. With the variation of the jet-to-jet spacing, the aluminum foam heat sink of 10 PPI show higher Nusselt numbers than the 20 and 40 PPI aluminum foam heat sinks. Further, the 10 PPI aluminum foam heat sink demonstrates 26% higher enhancement factor than the rectangular plate heat sink in the range of 7000$\leq$Re$\leq$11000.

• 대한기계학회논문집B
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• 제26권6호
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• pp.883-892
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• 2002

A numerical study has been carried out to investigate the flow and heat transfer from an aluminum foam heat sink in a confined channel. A uniform heat flux is given at the bottom of the aluminum foam heat sink, which is horizontally placed on the heated surface. The channel walls are assumed to be adiabatic. Cold air is supplied from the top opening of the channel and exhausted to the channel outlet. Comprehensive numerical solutions are acquired to the governing Wavier-Stokes and energy equations, using the Brinkman-Forchheimer extended Darcy model and the local thermal non-equilibrium model f3r the region of porous media. Details of flow and thermal fields are examined over wide ranges of the principal parameters; i.e., the Reynolds number Re, the height of heat sink h/H, porosity $\varepsilon$and pore diameter ratio $R_{H}$.

• 대한기계학회논문집A
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• 제27권10호
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• pp.1686-1694
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• 2003

The foam-filled tube beams can be used for the front rail and firewall structures to absorb impact energy during frontal or side collision of vehicles. In the case of side collision where bending is involved in the crushing mechanism, the foam filler would be effective in maintaining progressive crushing of the thin-walled structures so that much impact energy could be absorbed. In this study, bending behaviors of the closed-cell-aluminum-alloy-foam-filled stainless steel tube were investigated. The various foam-filled specimens including piecewise fillers were prepared and tested. The aluminum-alloy-foam filling offered the significant increase of bending resistance. Their suppression of the inward fold formation at the compression flange as well as the multiple propagating folds led to the increase of load carrying capacity of specimens. Moreover, the piecewise foams would provide the easier way to fill the thin-walled shell structures without the drawback of strength.

• 대한기계학회논문집B
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• 제25권9호
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• pp.1263-1271
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• 2001

An experimental study is carried out for an aluminum foam heat sink attached to an isolated heat source to evaluate high potential of aluminum foam as a heat sink with impinging jets. The effects of the pore density and the height of the aluminum foam heat sink, the jet Reynolds number, and the nozzle diameter are delineated in comparison with a conventional pin type heat sink. It is found that the aluminum foam with small pores is inefficient for the heat transfer enhancement due to the large flow friction at the given porosity. In the parameter ranges of the present study, the change in the nozzle diameter shows no significant effects on the surface temperature of the aluminum foam heat sink at a given Reynolds number. The heat transfer enhancement is strongly dependent on the jet Reynolds number and shows a maximum value at a moderate Reynolds number.

• 자원리싸이클링
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• 제10권4호
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• pp.42-47
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• 2001

알루미늄 드로스와 장석을 이용하여 무기발포재의 제조 가능성을 검토하여 폐기물인 알루미늄 드로스의 재활용 및 자원화의 다양성을 제시하기 위한 실험을 행하였다. 소성한 발포재의 경우 장석은 소성온도에서 용해되어 비정질상으로 전이하고 드로스 중의 성분들이 Spinel($MgA1_2$$O_4$)을 형성한다. 장석 55 wt%, 드로스 40 wt%, 벤토나이트 5 wt% 시료의 경우 소성온도 $1220^{\circ}C$에서 소성시간이 증가할수록 밀도는 0.91에서 0.65까지 감소하고, 흡수율은 약 2.5에서 1.7%의 범위의 값을 나타냈다. $1220^{\circ}C$에서 30분 소성할 경우 굽힘강도는 10.8 MPa이며, 열전도도는 0.34 W/m.K로서 최대치를 나타냈다.

• 한국융합학회논문지
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• 제2권3호
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• pp.1-6
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• 2011

대표적인 경량금속 중의 하나인 알루미늄 폼재의 연구동향을 기계적인 측면에서 고찰하여 보았다. 특히 기공(pore)을 가진 알루미늄재료는 난연성, 감쇠특성, 에너지흡수 성능 등 여러 측면에서 기존의 폴리머 폼재보다 우수한 기계적 성능을 가지고 있고, 더욱이 재활용이 가능하다는 면에서 환경보호에 관심이 집중되고 있는 현 시점에서 연구가 활발히 진행되고 있다. 폼재의 일반적 특성, 에너지 흡수 및 소음흡수 특성에 대해 살펴보고 폼재가 적용된 사례들에 대한 분석을 통해 향후 폼재와 외곽 구조재의 접합문제 등에 대한 제언을 하였다.