Experimental Study of The Influences of Inclination Angle and Heat Load on Loop Heat Pipe Thermal Performance
Keywords:
Inclination angle, Heat load, Thermal works performance, Loop heat pipe, Passive cooling system, Nuclear installationAbstract
The utilization of nuclear power brings out a lot of benefits in fulfilling human needs for power. However, the thermal accident caused by the failure of an active cooling system due to an earthquake followed by a tsunami, such as in the Fukushima Dai-Ichi Nuclear Power Plant, Japan, could be taken as a lesson learned to keep improving the operation safety aspects of nuclear installation. Loop heat pipe (LHP), as an alternative cooling system technology, could be utilized to handle thermal problems on nuclear installations. This research aims to understand the influence of the inclination angle and heat load on the thermal performance of LHP. The experimental investigation was performed with varying inclination angles of 0°, 2.5°, and 5°, and hot water temperatures of 60°C, 70°C, 80°C, and 90°C. The LHP used demineralized water as the working fluid. The demineralized water was charged to the evaporator with a filling ratio of 100%. LHP was vacuumed on 2.666,4 Pa. Atmospheric air was used as a condenser coolant and blown with a velocity of 2.5 m/s. The result of this experiment showed that LHP has the best thermal performance with the lowest thermal resistance of 0.0043 °C/W. This result was obtained when the LHP operated with a 5° inclination angle and hot water at a temperature of 90 °C. The conclusion from this research shows that LHP thermal performance is better as the inclination angle increases on LHP because the steam velocity formed is bigger, and condensate flows back to the evaporator faster.
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