• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1108-1111
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• 1999

The Peltier heat absorbed or evolved at the solidiliquid interface in the unidirectional solidification process could contribute to the increase of temperature gradient in liquid and growth velocity, and the enhancement of crystal orientation. In this study, in order to measure the Peltier heat generated at the solidiliquid interface as a way of application to crystal growth, the thermoelectric effects were investigated on the temperature changes at the solid- and liquid-phase of the same material and its interface. Through the theoretical consideration, it was possible to separate sole Peltier. Thomson or Joule heat from the temperature changes due to current density, polarity, and temperature gradient. Thomson coefficient of solid- and liquid-phase as well as Peltier coefficient at the solid/liquid interface could be obtained.

• Carbon letters
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• v.21
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• pp.8-15
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• 2017

The thermoelectric Seebeck and Peltier effects of a single walled carbon nanotube (SWCNT) quantum dot nanodevice are investigated, taking into consideration a certain value of applied tensile strain and induced ac-field with frequency in the terahertz (THz) range. This device is modeled as a SWCNT quantum dot connected to metallic leads. These two metallic leads operate as a source and a drain. In this three-terminal device, the conducting substance is the gate electrode. Another metallic gate is used to govern the electrostatics and the switching of the carbon nanotube channel. The substances at the carbon nanotube quantum dot/metal contact are controlled by the back gate. Results show that both the Seebeck and Peltier coefficients have random oscillation as a function of gate voltage in the Coulomb blockade regime for all types of SWCNT quantum dots. Also, the values of both the Seebeck and Peltier coefficients are enhanced, mainly due to the induced tensile strain. Results show that the three types of SWCNT quantum dot are good thermoelectric nanodevices for energy harvesting (Seebeck effect) and good coolers for nanoelectronic devices (Peltier effect).

• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1112-1116
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• 1999

Thermoelectric effects on the temperature changes at the solid- and liquid-phase and its interface were studied by using the unidirectional solidification of $\textrm{Bi}_{2}\textrm{Te}_{3}$. Cooling or heating effects measured with current density. polarity and current passing time were quite different. By separating sole Peltier, Thomson and Joule heat theoretically and experimentally, the Peltier coefficient at the solid/liquid interface of $\textrm{Bi}_{2}\textrm{Te}_{3}$ was -1.10$\times\textrm{10}^{-1}$V, and the Thomson coefficients of solid- and liquid-phase were 7.31\times\textrm{10}^{-4}V/K, 5.77\times\textrm{10}^{-5}V/K, respectively. When D.C. passed from solid-phase to liquid-phase during the crystal growth of $\textrm{Bi}_{2}\textrm{Te}_{3}$ the crystal with more directionality was obtained owing to increase of the temperature gradient in liquid by the Peltier cooling. But in reverse current direction, the crystallinity was not changed significantly.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.583-592
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• 2016

IMO (International Maritime Organization) in the UN (United Nations) set up that aim at reducing $CO_2$ emission from ship by up to 30 percent until 2030. The final purpose of this study is the development of marine thermoelectric generation system using waste heat from vessel of internal combustion engines. Before the development of marine thermoelectric generation system, this paper carried out the fundamental heat analysis of marine thermoelectric generation system. It was able to obtain the valuable results about the efficiency improvement of the thermoelectric generation system. The results is as follows : 1) It was confirmed that the efficiency of thermoelectric generation system improves to 8.917 % with increasing the temperature difference of peltier module by reducing the temperature difference between peltier module and heat source at the hot side. 2) System efficiency according to change in the external load resistance was confirmed that the change width of about 6 % which does not significantly occur. 3) System efficiency in the case stainless steel at the same condition is 8.707 %. System efficiency could be confirmed that the stainless steel is higher than duralumin (8.605 %), copper (8.607 %).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.409-414
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• 2012

A theoretical investigation to optimize thermoelectric elements for thermoelectric coolers was performed using a new one-dimensional analytic model. Mathematical expressions for the optimum current and the optimum length of a thermoelectric element, which maximize the coefficient of performance of thermoelectric coolers, were obtained. The optimum current is expressed in terms of the cooling load for a thermoelectric element, the hot and cold side temperatures and thermoelectric properties, but not the length of a thermoelectric element. The optimum current is proportional to the cooling load and decreases as the temperature difference between the hot and cold sides decreases. It is also shown that the optimum length of a thermoelectric element decreases as the cooling load increases.

• Journal of Institute of Convergence Technology
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• v.3 no.1
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• pp.19-23
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• 2013

This study is concerned with air-conditioning system in use of thermoelectric device. It is introduced that the well designed structures for better cooling & heating performance with high efficiency. And also it is performed that the system performance test of four types trial products for the use of hybrid commercial vehicle. System performance is affected by many component parts, especially heat sink design & power control method. It is applied that dual extrusive fin tube with buffer zone for the effective radiating of circulating liquid in tube. And also it is applied that power supply method with constant-current system. It is attained that system cooling capacity is 1.2kW, COP is 0.95.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1459-1462
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• 2007

In general a thermoelectric cooler (TEC) consists of a series of P type and N type thermoelectric materials sandwiched between two wafers. When a DC current passes through these materials, three different effects take place; Peltier effect, Joule heating effect and heat transfer by conduction due to temperature difference between hot and cold plates. In this study we have developed a micro TEC using $Bi_2Te_3$ (N type) and $Bi_{0.5}Sb_{1.5}Te_3$ (P type) thin films. In order to improve that performance of a micro TEC, we made 10 um height TE legs using special PR only for lift-off. We measured COP (coefficient of performance) and temperature difference between hot and cold connectors with current.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.7
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• pp.928-936
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• 1999

The electronic refrigerating kimchi jar operates with a low noise because it contains no compressor but it consumes more energy than that of an refrigerator with compressor. In this paper, the heat flow characteristics and cooling performance of an electronic refrigerating kimchi jar are studied by means of experiments. When the storage temperature is kept in a range of $-5.7^{\circ}C$ to $4.1^{\circ}C$. in the case of three ambient temperatures; $12.7^{\circ}C$, $22.3^{\circ}C$ and $32.2^{\circ}C$, the cooling performance of $20{\ell}$ kimchi jar is investigated. The experiments show that the temperature difference that exists between kimchi jar and its ambient provides a measure of the coefficient of performance of kimchi jar. It is also found that ratio of net pumping heat to the heat pumping rate of thermoelectric module is independent of the temperature difference.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.881-887
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• 2014

Micro-sized Peltier coolers are generally employed for uniformly distributing heat generated in the multi-chip packages. These coolers are commonly classified into vertical and planar devices, depending on the heat flow direction and the arrangement of thermoelectric materials on the used substrate. Owing to the strong need for evaluation of performance of thermoelectric modules, at present an establishment of proper theoretical model has been highly required. The design theory for micro-sized thermoelectric cooler should be considered with contact resistance. Cooling performance of these modules was significantly affected by their contact resistance such as electrical and thermal junction. In this paper, we introduce the useful and optimal design model of small dimension thermoelectric module.