Papers by Keyword: Heat Pipe

Abstract: Since their first introduction to the world, both heat pipe and nanofluid have caught the interest of many researchers. Heat pipe with its unique and exceptional capability in transferring heat passively and effectively, was studied intensively and developed extensively for many applications. While nanofluid with its higher thermal conductivity and some other upgraded properties compared to conventional fluid rose as appealing research subject especially on fluid and thermal research area. This study analyzes the utilization of CuO-water nanofluid on biomaterial wick heat pipe. Laboratory-developed CuO-water nanofluid was used as working fluid for vertically straight-shaped biomaterial wick heat pipe. From the experiment, it was shown that the application of CuO-water nanofluid reduced the heat pipe thermal resistance up to 83%. It was figured out that this enhancement is due to the combination of higher thermal conductivity and better wettability of the fluid. It was also found that the heat pipe with nanofluid did not show significant degradation though being inactivated for several weeks. However, it was figured out that unlike the application of low concentration nanofluid, application of high concentration nanofluid was insignificant in improving thermal performance of the heat pipe.

Abstract: In order to study the influence of various factors on the heat pipe heat transfer performance, the heat transport limit was taken as test index, nine groups of heat pipe factors matching experiments were carried out based on the orthogonal test method. Four heat pipe internal factors including wick, work media, mass concentration and filling ratio were studied. The results show that the wick has the greatest influence, filling ratio ranks the second, while the work media and mass concentration are not so obviously; the wick and work filling ratio both have significant influences on test index, while work media and mass concentration have little significance.

Abstract: A trend towards increasingly dense and compact architectures has led to unmanageably high heat fluxes in electronic components. A novel heat pipe will be developed. Heat pipe designed is based on the flat plate heat pipe and pulsation heat pipe effective combination. Channel quantity is greatly increased ,as well as compact and homogeneous red copper pulsation plank is severed as the wick，dense and connected channels are served as the passage of the working fluid.

Abstract: Combining high thermal conductivity and high latent heat of phase change Materials (PCM) with heat pipe that has strong ability of heat transfer. A three-dimensional transient heat-transfer model was set up to simulate the temperature distribution in the lithium-ion battery under different conditions of heat generation rate and different ambient temperature. The study revealed that composite cooling system keep the battery temperature below 40.2°C on average working condition, the highest temperature was not exceed 48.7°C even under stressful conditions. However, use PCM without heat pipe as cooling system, the temperature was 2~6°C higher than composite cooling system at the same condition. The composite cooling system was superior to PCM cooling system, especially in high heat generation rate and high ambient temperature.

Abstract: Three heat pipes with nanofluids of Al₂O₃-water, CuO-water and SiO₂-water were tested experimentally. The temperature distribution of their start-up process was analysed, and compared the heat pipe with water. The results showed that the start-up way of heat pipe filled with nanofluids was coincident, the heat pipe filled with nanofluids showed a lower start-up temperature and a shorter start-up time in evaporator section compared with heat pipe filled with water, the temperature drop between evaporator section and condenser section for the heat pipe filled with nanofluids were reduced by 2-5°C than that of the heat pipe filled with water. The effect of the length of the heating section of heat pipe filled with nanofluids on the start-up process was little.

Abstract: In order to ensure proper temperatures for electronic equipment and to meet the increasing heat dissipation capacity needs of airborne electronic equipment, a suitable heat-pipe for use in aircraft equipment needs to be found. Considering both the acceleration and the changes in tilt angle of the aircraft, performance analysis of five main types of heat-pipes showed that dual compensation chamber loop heat pipe and micro-channel plate heat pipe were the most suitable for use in airborne electrical equipment.

Abstract: Blast furnace in steel industry consumes about 9% of annual energy consumption of domestic industry. Blast dehumidification is an important way to increase production and decrease coke ratio of blast furnace. The energy-saving blast dehumidification system uses heat pipe for air pre-cooling and re-heating before and after dehumidification. Because temperature of air has been decreased to a certain extent by pre-cooling, dehumidification energy consumption could be decreased. After dehumidification, temperature of the air could be increased by re-heating, thus the threshold temperature of the air sent into hot blast stove could also be increased, it would save energy and increase production of blast furnace. But this system has an extra heat pipe heat exchanger compared with traditional one, so the construction cost and pressure drop may be higher.

Abstract: An experimental facility to examine the effect of carbon nanotubes (CNT) on the performance of a horizontal V-grooved heat pipe was build. The circular heat pipe was made of copper with an inner diameter of 10 mm and equipped with 10 axial V-grooves with 1 mm depth and 1 mm mouth. The experiment was performed using water as working fluid with mass percentage of CNT of 0%, 1%, 3% and 5%. The optimum fill ratio of the heat pipe was first determined by examining the fill ratio effect on the total resistance. This optimum fill ratio was then used throughout the whole experiment. The evaporator of the heat pipe was heated using a copper heater block equipped with 6 cartridge heaters. The power input to the evaporator was varied from 60 W to 240 W in steps of 60 W with maintaining steady-state operation at each power level. The condenser was cooled by a water jacket fed by a chiller. The surface temperature of the heat pipe was measured by 7 K-type self-adhesive thermocouples connected to data acquisition system. The experimental results showed that the performance of the heat pipe improved with the use of CNT-water mixture in terms of a reduction in the thermal resistance. The results also showed that this enhancement is a function of the amount of CNT additive.

Abstract: The findings of new energy and energy harvester are the important issues for the lacking of fossil energy. For the purpose of the effective usage of supercritical CO₂ flowed from the product well of CO₂ EGS (Enhanced Geothermal System), an innovative heat pipe heat exchanger (Hx) is designed and practiced in this study. This study presents an innovative Hx of heat pipe for extracting the heat from CO₂ or warm gas. By using the heat pipe for cooling gas is the fundamental idea of this Hx. The experimental apparatus of Hx consists a heating blower to blow out hot gas, a circulating cool water device, and a set of heat pipes. The efficiency of Hx is approved as the increasing air velocity and the more fins gradually. This innovative heat pipe exchanger is proofed through our experiment. This heat pipe Hx is suitable for the application of enhanced geothermal system (EGS) and more energy harvesting application.

Abstract: In the long run, the problem of high temperature has been existed in a companys injection molding machine controller. In order to solve the heat dissipation problem, two kinds of heat pipe heat dissipation schemes are designed, CFD software ICEPAK is used in the report to make a numerical simulation as well as a simulation analysis of the Heat pipe cooling scheme. By comparing two kinds of cooling mode heat pipe cooling effect and structure process, Vertical-type heat pipe cooling solution that meets the cooling requirements and makes heat-sensitive components stay away from high-temperature, furthermore heat pipe processing technology is relatively simple.