Impact of Eccentric Tube Shapes and Heat Pipes on Phase Change Material’s Thermal Charging

The thermal charging performance of phase change material (PCM) in an eccentric tube and shell system is investigated through numerical analysis. Various shapes of eccentric tubes, including circular, semi-circular, triangular, inverted triangular, square, and C-shape, are considered. The PCM mass and shell diameter remain consistent across all tube geometries. Moreover, vertical heat pipes (HPs) are utilized to connect the heat source eccentric tube wall and the PCM stored in the shell. The examination evaluates the consequences of the tube shape and HPs using liquid fraction, temperature time history and contours, enhancement ratio, total energy storage, and mean power as performance indicators. The findings demonstrate that non-circular cases exhibit a shorter melting time than circular tube cases. The C-shape tube has the (Largest) 30.3% less thermal charging time than the circular tube, and the mean power is 39% higher. Moreover, adding HPs increases the mean power by up to 241% more than the circular tube, and reduces thermal charging time by about 72.2%. The inverted triangular tube exhibits the highest energy charge capability within the selected options.