Effect of Steps Height and Glass Cover Angle on Heat Transfer Performance for Solar Distillation: Numerical Study

Productivity and heat transfer in the stepped solar still by varying the glass cover angle and steps height were investigated numerically. Mass, momentum, energy, and diffusion equations were used for simulating the distillation process in order to obtain the productivity and heat transfer coefficient. Further,the numerical simulation validated by existed experimental data. Simulation results indicated the highest freshwater production in comparison with experimental set up condition, which is at the step height ۴cm and glass cover angle ۶۰.۲۳◦, belongs to the step height of ۵.۵cm with ۱۴۰۰ mL/m۲hr, namely ۹۱⁒ increase and much less for the step height of ۱cm with ۳۵۰ mL/m۲hr, namely ۵۲⁒ decrease. Most increase in Nusselt number obtained for the angle of ۵۵◦ with Nu=۱۲.۰۳ with ۲۹⁒ increase and much less for the angle of ۶۵◦ with Nu=۸.۱۶ with ۱۲⁒ decrease. In addition, most and less variation of the heat transfer coefficient obtained for the step height of ۵.۵cm with hc=۴.۰۴ W/m۲ K, with ۳۹⁒ increase and for the step height of ۱cm with hc=۲.۱۸ W/m۲ K, with ۲۴⁒ decrease, respectively.

Keywords:

stepped solar still , passive solar still , Productivity , Numerical analysis