Comparative study of the energy performance of two thermosiphon solar collectors with different water channels: channel in round tubes and channel under flat plate

This theoretical study focuses on the comparison of the performance of two solar collectors with the same characteristics except for the different water circulation channels. One of the channels is copper tube of 10 mm diameter and the other is rectangular with 5 mm height. The method used to resolve the system of equations from thermal balances is that of Newton-Raphson. The code of our simulations has been validated. The results of our simulations show that the water temperature and thermal efficiency are high in the collector with rectangular channel while the global coefficient of heat loss and the number of entransy destroyed are higher in the collector equipped with round tube conduit.