دراسة نظرية وعملية لتاثير كمية التدفق ونسبة التركيز على اداء مجمع شمسي من نوع القطع المكافئ الاسطواني المغلق في مدينة كركوك

Theoretical and Experimental Study for the Effect of Mass Flow Rate and concentration ratio of PTC Close Type Solar Collector in Kirkuk City

Theoretical and experimental study has been used to analysis close type solar collector PTC in south of Kirkuk city in Iraq 43°.53 longitude, 35°.25 width with elevation of 217 m. The mass flow rate of water and concentration ratio are (0.00083, 0.0011, 0.00138, 0.00166 Kg/sec) and (10, 14, 22) respectively. The measurements and calculations were conduct, which lasted for two season winter and summer, from 9AM to 5PM. The experimental study show that the efficiency of PTC in summer increase in winter from (5 - 7)%, the efficiency is increase with increasing of mass flow rate consequently, then the efficiency is a function of mass flow rate. The efficiency of PTC increased with decreasing of concentration ratio. The maximum value of efficiency is 20% in summer decreased to 15% in winter when the mass flow rate 0.00083 Kg/sec with concentration ratio 22 then increase to 33% in summer and 22% in winter at the same concentration ratio with mass flow rate of 0.00166 Kg/sec, also the experimental study show that the efficiency in summer higher than it in winter by about (10 - 15)% is increased with decrease concentration ratio to reach in summer to 27% and 18% in winter when the mass flow rate 0.00083 Kg/sec with concentration ratio 10 while the efficiency is 42% in summer and 29% in winter at maximum mass flow rate of 0.00166 Kg/sec, and the same concentration ratio . The theoretical study has been performed according to ASHRAE 93-1986 (RA-91) for assessment of performance of PTC solar collector. The theoretical results showed that the theoretical efficiency is 50% and increase to reach 63% with increase the mass flow rate from minimum to maximum value when the concentration ratio is constant. The reason of this error because of the necessary assumption are used in ASHRAE 93-1986 (RA-91) such as steady state conditions which are difficult established in solar energy.