09. Heat and Mass Transfer

Right now, Indonesia is at a crossroads. This country which is so heavily dependent on fossil fuels as the source of energy - has commitments for decarbonization and a sustainable energy transition - before the effect of irreversible damage caused by climate change ruins the nation’s environment. But in reality we are way off track from meeting our targets. So it is everyone’s duty to give more effort, especially in conserving energy. In Indonesia – the buildings sector is consistently the largest yearly consumer of energy – where a significant portion of said energy is used for space cooling using AC systems. A lucrative opportunity in conserving energy for buildings is the usage of passive cooling technology – the example of which is the usage of the Closed Loop Pulsating Heat Pipe (CLPHP) on the envelopes of the building – such as the roof. The performance of CLPHP hinges on many factors, one of which is the inclination angle. In this research, the goal is to find the optimal inclination angle for the CLPHP so that it could be applied to the roofs of buildings in order to cooling load. Research was conducted for the CLPHP with De-Ionized Water (DI Water) and Acetone working fluids under 5 inclination angles (15°, 25°, 30°, 35°, and 45°) and 3 heat inputs (50W, 55W, 60W). Results from the experiment show that the optimal performance is found in CLPHP with DI Water at 45° inclination and 60W of heat input with a thermal resistance of 0,51 °C/W and effectiveness of 63,75%. It was also found that higher inclination played significant part in increasing performance for CLPHP with DI Water, but for CLPHP with Acetone the performance tends to be stable under all inclinations.