Abstract
This study compares and contrasts the desalination efficiency of tubular solar still using cylindrical and rectangular troughs when operating under a vacuum. For this, a two-dimensional code was created using the Comsol Multiphysics. The mass and heat transfer, inside the tubular solar still with the two different types of troughs, was simulated parametrically. The effect of the radius of the cylindrical trough, the square rib of the rectangular trough and the vertical elevation of the trough on heat and mass transfer were investigated at the same volume of seawater introduced initially. The numerical results revealed that the efficiency of the water productivity using cylindrical trough is significantly better than with rectangular trough when it is placed in the middle of the tubular shell. The opposite case of the 2 types of troughs is established when the trough advances towards the upper side of the glass cover where the condensation occurs.