Manuscript Information Authors

[1]	Nassar Yasser Fathi, Mechanical Engineering Department, Engineering and Technology Faculty, Sebha University, Brack Al-Shati, Libya.

Abstract

The main purpose of the present work is to study the thermal behaviour of a typical domestic solar water heating system (DSWHs) consists a flat-plate solar collector, thermal storage tank, pumps, piping and control unit, leading to get out the optimum design and operating parameters such as (mass flowing through the solar collector array, area of solar collectors and the volume of the storage tank) that matched the requirement of people from hot water. The idea is, all the water need flowing directly through the collector and then accumulating in the thermal storage tank, by this method we improved the thermal behaviour of the solar collector, because the inlet temperature to the collector equals to the ambient temperature, at this point we have a maximum efficiency. Furthermore, we reduce the volume of the storage tank, because some of the load will be extracted instantaneously from the collector. Equation to predict the volume of the storage tank for continuous load has been presented. To achieve this purpose a work sheet of MS-Excel was prepared in order to evaluate the influence of all mentioned above parameters on the water temperature in the storage tank. The obtained results show that, for Libyan typical family which consumed about 250 letter of water per day at temperature not less than 50°C with total daily solar radiation of 5.55 kWh/m²/day and the average ambient air temperature is 29.7°C, the optimum parameters were found as: the solar collectors area is 2.4m², the mass flow rate through the collector is 4.1336 g/s/m² and the volume of the storage tank is 135 L. The maximum water temperature was found 68°C and the minimum temperature is 50.5°C.

Keywords

Solar Storage Tank, Solar Collector, Optimum Tank Volume, Optimum Mass Flow Rate, Solar Water Heating

Reference

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