Authors : Heba Qasim Mohammed, Ali Sh. Baqir and H.S. Khwayyir Hasan
Abstract: This study aims to study experimentally with and without the effects of small air bubble injection on the efficiency of a flat plate solar collector with tube rises for open flow system. The variation of the thermal efficiency of the solar flat plate collector due to both different of the water flow rate and due to the air bubbles injection with air flow rates are evaluated. A new experimental procedure for injecting small air bubbles into the riser tubes of solar flat plate collector is proposed. The comparison between the effects of forced water flow rates and air bubbles injection on the solar flat plate thermal efficiencies with a variation of solar radiation intensity were investigated. Water and air flow rate were changed between 1.5-2.5 LPM with inlet water temperature ranged between 19-23.5°C. Observations showed that the injecting of air bubbles inside the solar flat plate tubes risers play key roles on the effect of thermal efficiency more than that of using the water flow rate without air bubbles injection. Small air bubbles injecting into the risers tubes of the flat solar collector causes enhancement of the thermal efficiency and it increased 3.5-5.25% depending on air flow rate.
Heba Qasim Mohammed, Ali Sh. Baqir and H.S. Khwayyir Hasan, 2020. Effects of Air Bubble Injection on the Efficiency of a Flat Plate Solar Collector: An Experimental Study for the Open Flow System. Journal of Engineering and Applied Sciences, 15: 1703-1708.