Figure 6.

The predicted and measured temperature and relative humidity of the air leaving the forced convection still.

Figure 7.

The predicted and measured temperature and relative humidity of the air leaving the preheater.

The Mathematical Model of Basin-Type Solar Distillation Systems DOI: http://dx.doi.org/10.5772/intechopen.83228

Figure 8.

4.2 The active solar distillation system with external condenser and enhanced

To simulate the performance of the active distillation system, the computer program is first input with the measured weather parameters of the site and the measured values of the air entering the still's relative humidity and temperature. The results of the simulation program include still water temperature, glass temperature, basin temperature, air leaving the still temperature and relative humidity, air leaving the condenser temperature, and air leaving heat recovery's temperature and relative humidity, as well as the distillate production from the glass and from the condenser. Figure 6 shows the measured and predicted temperatures and relative humidity of the air leaving the still, while Figure 7 shows those of the air leaving the preheater. Figure 8 shows the air leaving the still calculated and measured moisture content, and Figure 9 shows the basin water calculated and measured temperatures. Figures 10 and 11 correspondingly show the calculated and

The predicted and measured temperature and relative humidity of the air leaving the forced convection still.

The predicted and measured temperature and relative humidity of the air leaving the preheater.

measured distillate yields from the glass and the condenser.

water recovery

Distillation - Modelling, Simulation and Optimization

Figure 6.

Figure 7.

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The predicted and measured moisture content of the air leaving the still.

Figure 9. The predicted and measured temperature of the water in the still.

Figure 10. The predicted and measured distillate condensed on the glass of the still.

Figure 11. The predicted and measured distillate collected from the condenser of the still.

As shown in Figure 6, the mathematical model can predict reasonably well both the actual values and the trend of the temperature of the air leaving the still. The maximum error of the calculated temperatures compared to measured values is 5°C and occurs in the early afternoon. The average errors in the relative humidity calculation are around 10% with maximum error values up to 20%. In most cases, the computed values are lower than the measured ones. Figure 8 once again confirms that the mathematical model underestimates the moisture in the air leaving the still in the middle of the day. At other times, the predicted and measured computed moisture contents of the outlet air are similar, which shows the observed variations in relative humidity at these times are due to difference between the predicted and measured air temperatures.
