EXPERIMENTAL INVESTIGATION OF VERTICAL ORIENTATION CLOSED-LOOP PULSATING HEAT PIPE WITH DIFFERENT DIMENSION

The vertical closed-loop pulsating heat-pipe systems with different dimension and heat input. Numerous test systems were constructed using copper capillary tubes with assorted inner diameters, evaporator lengths, CLPHP. It is very efficient device for dissipating heat from the device. But new technology introduces which is nothing but Pulsating Heat Pipe. In this experiment three different configurations of copper capillary tubes having internal diameters 1.5mm, 2.0 and alternate internal diameter. The experiments are conducted on vertical orientations for different heat loads varying from 10 W to 130 W in steps of 10 W. The PHP is tested on Ethanol, as working fluids for different fill ratios viz. 30%, 50%, and 70%, the temperature distribution across the heat pipe was measured and recorded using thermocouples. The thermal resistance and the overall heat transfer coefficient are evaluated. The experimental results demonstrate the heat transfer characteristics, lower thermal resistance and higher heat transfer coefficient of CLPHP are found to be better at a fill ratio of 50% for different heat input and also the thermal performance of alternate internal diameter i.e. 1.5mm and 2mm of pulsating heat pipe gives better result over the uniform diameter of CLPHP