Experimental study on the thermal performance of a solar collector and the effect of the tilt angle on the collector efficiency

Effect of inclination of the absorbent metal plate on the thermal performance and instantaneous efficiency has been investigated in a solar heating system using solar collectors. Two various metallic plates had been designed for experimental research, In the first type (Type I) flat plate is used with (90°) inclination angle from horizon, while (60°) inclination angle from horizon is used in the second type (Type II) flat plate. The experimental study and the collectors was manufactured in Tikrit (34° 35 N, 43° 73E), Iraq. Results of the experimental study show that inclination angle (60°) is the best compared with (90°) to absorb largest amount of solar radiation intensity. The optimum value of thermal performance and instantaneous efficiency was determined in (Type II). The effect of the changing air flow rate was also investigated. Three different air flow rates had been studied (0.2, 0.4, 0.6 m/sec), The results showed that the efficiency increases with increasing air flow rate, temperature difference decreases with increasing air flow rate.