• The Transactions of the Korean Institute of Power Electronics
• /
• v.9 no.4
• /
• pp.350-355
• /
• 2004

This paper deals with the design of a heat dissipation system, which consists of a heat source of power semiconductor devices, a heat sink ;md a fan for the forced air cooling. It suggests the method of appropriately dividing the whole heat transfer system into analytical subsystems and also presents the correspondent analytic or experimental design equations for the subsystems. The experimental results on the designed heat dissipation system for the 400kW IGBT inverter show less than 10［%］ error with respect to the design temperature and therefore verify the validity of the proposed analytical design method in the steady state.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.15 no.1
• /
• pp.27-34
• /
• 2010

To dissipate the heat generated from the switching devices in the inverter system of HEV, the water cooling structure is proposed. The bolt type cooling structure has a problem such as water leakage for high pressure of water, therefore the proposed cooling structure applied pipe structure in the heat sink. The heat dissipation characteristics for various structures of water channel and distance between heat source and water channel was analyzed through the simulation. heat dissipation effect for two types of water cooling structures was investigated. Based on the simulation results, two types of water cooling system for 30kW inverter system of HEV were manufactured and the heat dissipation effect was verified.

• Transactions of the Korean hydrogen and new energy society
• /
• v.31 no.1
• /
• pp.112-121
• /
• 2020

In this work energy and entransy characteristics of heat exchangers are analyzed for 12 different flow arrangements of heat exchangers. The dimensionless parameters are number of entransy dissipation (Ng), number of entransy dissipation-based thermal resistance (Nr), and entransy dissipation-based effectiveness of heat-exchanger (εg). The dimensionless parameters are expressed analytically in terms of the effectiveness of heat exchanger (ε), heat capacity ratio (c), and number of transfer unit (N) for optimal performance of heat exchangers. Results showed that the dimensionless parameters based on the entransy dissipation can be useful concepts for optimal design of heat exchangers.

• Journal of Advanced Marine Engineering and Technology
• /
• v.40 no.8
• /
• pp.686-691
• /
• 2016

This paper employs numerical tools to obtain an optimal thermal design of a heat exchanger with plain-fins. This heat exchanger is located at the condensing section of a crevice-type heat pipe. The plain-fins in the heat exchanger are radically mounted to two tubes in the condensing section. To obtain the optimal design parameters, a computational fluid dynamics technique is introduced and applied to different placement configurations in a system module. Owing to its effects on the heat pipe performance, the temperature difference between the tube surfaces and ambient air is investigated in detail. A greater heat dissipation rate occurs when the plain-fin offsets change from 2 to 3 mm. When this temperature difference is ${\Delta}T=70^{\circ}C$, the upper part of the plain-fins undergoes an accumulation of heat. At below $70^{\circ}C$, the dissipation of heat is accepted. A rectangular plain-fin geometry with varying widths and heights does not have a significant impact on the heat dissipation through-out the overall system. In addition, the temperature distributions between different plain-fin pitches show an equal profile even with different fin pitches.

• Journal of IKEEE
• /
• v.25 no.3
• /
• pp.528-533
• /
• 2021

This paper presents the PCB heat dissipation characteristics of high density DC-DC converter for electric vehicles. This paper also analyzes the heat dissipation structure of the high density DC-DC converter and optimizes the PCB heat dissipation design of the high density power system through thermal analysis simulation. Based on heat transfer theory, the thermal path of general electronic devices is analyzed and the thermal resistance equivalent circuit is modeled in this paper. Additionally, the thermal resistance equivalent circuit of the 500W synchronous buck converter, which is addressed in this paper, is modeled to present a structural heat dissipation path for better thermal performance. The validity of the proposed scheme is verified through the thermal analysis simulation results and experiments applying multi-surface heat dissipation structure to a 500[W](12[V], 41.67[A]) synchronous buck converter prototype with an input voltage 72[V].

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.2286-2291
• /
• 2008

Some electronics component, which is adopted as components of antenna for radar or satellite system and used for amplifying signals to transmit, is accompanied by very significant heat dissipation levels because of the inefficiencies inherent in radio frequency wave generation. So, proper cooling performance for that system is base requirement for thermal design. On this paper, we applied heat spreading structures to reduce thermal density and find the optimum values of heat sink design factors through theoretically, numerically and evaluated by product test. As the results, the performance of the cooling system shows the propriety of cooling high density heat dissipation electronics components.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.5
• /
• pp.105-110
• /
• 2020

The global battery market is rapidly growing due to the development of vehicles(EV) and wireless electronic products. In particular logistics robots, which hielp to produce EVs, have attracted much interest in research in Korea Because logistics sites and factories operate continuously for 24 hours, the technology that can dramatically increase the operation time of the logistics equipment is rapidly developing, and various high-level technologies are required for the batteries used in. for example, logistics robots. These required technologies include those that enable rapid battery charging as well wireless charging to charge batteries while moving. The development of these technologies, however, result in increasing explosions and topical accidents involving rapid charging batteries These accidents due to the thermal shock caused by the heat generated during the charging of the battery cell. In this study, a performance evaluation of a heat dissipation design using infrared thermal imaging was performed on an energy storage systrm(Ess) applied with an internal heat conduction cooling method using a heating plate.

• Proceedings of the KIPE Conference
• /
• 2003.07a
• /
• pp.10-14
• /
• 2003

This paper deals with the design of heat dissipation system using the forced air cooling method. It suggests the method of appropriately dividing the whole thermodynamic system into analytical subsystems and also presents the correspondent analytic or experimental equations to subsystems. The experimental results on the designed thermodynamic system for 400kw 1GBT inverter show the validity of the proposed design method in the steady state.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.19 no.2
• /
• pp.8-19
• /
• 2023

Hydronic heated road pavement (HHP) systems have well studied and documented by many researchers. However, most of the systems run on asphalt, only a few are tested with concrete, and there rarely is a comparison between those two common road materials in their heating and cooling performance. The aim of this study is to investigate the thermal performance of the HHP, such as heat dissipation performance in winter season while focusing on the surface temperature of the concrete and asphalt pavement. For preliminary study a small-scale experimental system was designed and installed to evaluate the heat transfer characteristics of the HHP in the test field. The system consists of concrete and asphalt slabs made of 1 m in width, 1 m in length, and 0.25 m in height. In two slabs, circulating water piping was embedded at a depth of 0.12 m at intervals of 0.16 m. Heating performance in winter season was tested with different inlet temperatures of 25℃, 30℃, 35℃ and 40℃ during the entire measurement period. The results indicated that concrete's heating performance is better than that of asphalt, showing higher surface temperatures for the whole experiment cases. However, the surface temperature of both concrete and asphalt pavement slabs remained above 0℃ for all experimental conditions. The heat dissipation performance of concrete and asphalt pavements was analyzed, and the heat dissipation of concrete pavement was greater than that of asphalt. In addition, the higher the set temperature of the circulating water, the higher the heat dissipation. On the other hand, the concrete pavement clearly showed a decrease in heat dissipation as the circulating water set temperature decreased, but the decrease was relatively small for the asphalt pavement. Based on this experiment, it is considered that a circulating water temperature of 20℃ or less is sufficient to prevent road ice. However, this needs to be verified by further experiments or computational fluid dynamic (CFD) analysis.

• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.8
• /
• pp.801-806
• /
• 2015

The experimental analysis of a crevice-type vapor chamber heat pipe (CVCHP) is investigated. The heat source of the CVCHP is a high-power light-emitting diode (LED). The CVCHP, which exhibits a bubble pumping effect, is used for heat dissipation in a high-heat-flux system. The working fluid is R-141b, and its charging ratio was set at 60 vol.% of the vapor chamber in a heat pipe. The total thermal conductivity of the falling-liquid-film-type model, which was a modified model, was 24% larger than that of the conventional model in the LED package. Flow visualization results indicated that bubbles grew larger as they combined. These combined bubbles pushed the working fluid to the top, partially wetting the heat-transfer area. The thermal resistance between the vapor chamber and tube in the modified design decreased by approximately 32%. The overall results demonstrated the better heat dissipation upon cooling of the high-power LED package.