In this work, a novel single-slope solar distillator of floating perforated absorber
inserted with wicks (cotton ribbons), and a stepped distillator are designed and
manufactured with the aim of developing the conventional distillator. They are
examined experimentally at Baghdad, Iraq (33.3°N Latitude, 44.4°E Longitude) in order
to enhance the freshwater productivity and the efficiency of the conventional
distillator. Results showed that the daily productivity and efficiency of the stepped
distillator are higher than that for conventional solar distillator by 30% and 36.19%
respectively. The daily productivity and thermal efficiency for the distillator with the
floating absorber are higher than that for the conventional distillator by 16% and 26%
respectively. Daily productivity and the efficiency of the stepped distillator are higher
than that for the distillator with floating absorber by 11.8 % and 32.9 % respectively. It
has been concluded that the stepped distillator is higher productivity and efficiency
than the conventional distilled and the distillator with the floating absorber.

Flow and heat transfer are simulated numerically in a 3-dimensional square duct supplied with circular turbulators for different values of the turbulator height to the duct height (Blocking ratio BR). The investigated blocking ratios of these circular obstacles are 0.1, 0.15 and 0.2. Reynolds number for all cases is fixed at 5477. Top and bottom faces of the duct in the test region are subjected to 200 W/m2 heat flux. Turbulators number effect is examined in a range of (1-2-5-7). The fixing angle is taken of range (0, 30, and 45). The influence of these parameters on both heat transfer and fluid flow are examined. Ansys-Fluent 18 is implemented to perform the numerical simulation. The simulation of fluid flow is performed using realizable k-ε turbulence model. It was found that the presence of these turbulators has a significant effect on the heat transfer. Further that the heat transfer rate directly proportional to the blocking ratio, number of turbulators, and fixing angle. In general, the enhancement ratio of heat transfer could reach 30%.