• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.228-228
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.11a
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• pp.104-105
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1300-1300
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• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.741-742
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• 2011

XRD 결과와 TEM 분석으로부터 열처리효과에 따른 Bi-Te 박막의 미세구조 변화를 확인하였다. $Bi_2Te_3$ 상이 $SiO_2$ 와 Bi-Te 박막의 경계면을 따라서 성장하였고 이는 열전성능에 중요한 영향을 미치는 것을 확인하였다.

• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.991-997
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• 2003

The effect of A1$_4$C$_3$ additive on the thermoelectric properties of SiC ceramics were studied. Porous SiC ceramics with 47∼59% relative density were fabricated by sintering the pressed $\alpha$-SiC powder compacts with A1$_4$C$_3$at 2100∼220$0^{\circ}C$ for 3 h in Ar atmosphere. Crystalline phases of the sintered bodies were identified by powder X-Ray Diffraction (XRD) and their microstructures were observed with a Scanning Electron Microscope (SEM). In the case of A1$_4$C$_3$ addition, the phase transformation of 6H-SiC to 4H-SiC could be observed during sintering. The Seebeck coefficient and electrical conductivity were measured at 550∼95$0^{\circ}C$ in Ar atmosphere. In the case of undoped specimens, the Seebeck coefficients were positive (p-type semiconducting) possibly due to a dominant effect of the acceptor impurities (Al, Fe) contained in the starting powder and electrical conductivity increased as increasing sintering temperature. Electrical conductivity of A1$_4$C$_3$doped specimen is larger than that of undoped specimen under the same condition, which might be due to the reverse phase transformation and increasing of carrier density. And the Seebeck coefficient of A1$_4$C$_3$ doped specimen is also larger than that of undoped specimen. The density of specimen, the amount of addition and sintering atmosphere had significant effects on the thermoelectric property.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.30-35
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• 2021

The present study examined the effects of various guide fin structures and boundary parameters on the thermal performance of heat exchangers used in heat recovery thermoelectric generators. The heat transfer rate and pressure drop of the heat exchangers without fins, with circular fins, with triangular fins, and with combined circular and triangular fins were simulated numerically using ANSYS 19.1 commercial code to confirm the effect of the guide fin structures. The heat transfer rate of the heat exchanger with combined fins was 27.0%, 5.2%, and 1.5% higher than those without fins, with circular fins, and with triangular fins, respectively. The pressure drop characteristic of the heat exchanger with the combined fins was 28.3% higher than that without fins but 9.2% and 10.5% lower than those with circular fins and with triangular fins, respectively. The heat exchanger with combined fins as the optimal model showed the highest heat transfer rate of 5664.9 W and pressure drop of 1454.02 Pa for highest hot gas temperature, maximum flow rates of hot gas and coolant, and lowest coolant temperature.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.71-76
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• 2013

This study is experimentally performed for using the oyster shell as a desiccant in the batch type system. The peltier element(thermoelectric device) is used for absorbing and releasing the adsorption and desorption heat generation. The cooling and heating effects of peltier element exist in this experiment and these effects are generally known phenomena among some references. The increase in electric current induced into peltier element is effectively release the heat generation of adsorption and desorption. Consequently, the non-dimensional adsorption and desorption amount would increase with increase in electric current. However, in the case of adsorption, the increase of induced current into peltier element, the heat of cold side can not release sufficiently. So the heat of hot side of peltier is transferred into the cold side.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.268-268
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• 2011

열전소자를 사용하여 발광다이오드의 발열을 개선한다. 열전소자(Thermoelectric device: TED)의 펠티에효과(Peltier effect)를 이용하여 발광다이오드(Light Emitting Diodes: LED)의 접합온도 (Junction Temperature)를 제어한다. 열전소자의 구동 전력을 제어하여, 발광다이오드의 사용 전류에 대한 접합온도의 특성을 조사한다. 열전소자의 입력 전력 0.2W에 대하여, 일반 조명용 또는 표시 장치로 사용되는 1W급 고전력 LED를 정격전류(350 mA)로 구동할 때 접합온도를 최저 $69^{\circ}C$로 유지할 수 있다. 열전소자의 구동 전력이 0.2W일 때, 발광다이오드의 접합온도 $110^{\circ}C$에 대하여 최대 사용 가능 전류는 560 mA로 예측된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4723-4728
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• 2014

In this study, a thermoelectric module (TEM) and a diesel engine were modeled using 1-D commercial software AMESim, and the performance of the TEM was evaluated when the engine was operated under the NEDC driving cycle. The goal of TEM modeling was to investigate not only the waste heat recovery (WHR) rate and energy converting efficiency, but also the heat transfer rate by taking the materials characteristics into account. In addition, a diesel oxidation catalyst (DOC) was designed, and it was found that the waste heat recovery with TEM affects the activation of DOC and alters engine exhaust composition. The simulation indicated that the WHR using TEM is beneficial for decreasing the fuel consumption of vehicles, but the reduction in the exhaust temperature affects the activation of DOC, resulting in an approximately 14% increase in CO and HC emissions. Therefore, the effect of waste heat recovery on the automotive emission characteristics must be considered in the development of automotive engine WHR systems.

• Journal of Energy Engineering
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• v.2 no.1
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• pp.95-103
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• 1993

A conceptual thermoelectric heat pump(cooling mode) of small capacity is designed. Its performance is investigated through parametric analysis. COP and cooling capacity decease as the ambient temperature increases with ${\mu}$, J, T$\sub$wi/, fixed. To design a system of fixed capacity comes to calculate ${\mu}$ and J when T$\sub$wi/, and T$\sub$a/ are given. As v is fixed by semi-conductor manufacturers, optimum combination of n and I should be searched for ν. Optimum current could be calculated using ${\mu}$-J curve and optimum value of ${\mu}$. COR$\sub$R/ increases as water flow rate increases and T$\sub$a/ decreases. The effect of heat transfer coefficient at hot(heat releasing) side is more significant than that at cold(heat absorbing) side.