Document Type : Research Paper


Department of Electromechanical Engineering, University of Technology, Baghdad, Iraq.


In this paper, experimental study on double pass solar air heater with wavy fins absorber has been investigated. The fins attached to the upper and lower surfaces of the absorber. Two wavy fins arrangement (3 and 7 fins) have been investigated with plan absorber by changing solar radiation intensity (500, 600, 700 and 800 W/m2), air mass flow rate form 0.008575 kg/s to 0.0214375 kg/s. The results of wavy finned absorbers are compared with plane and the improving in thermal efficiency reached 80% and 84% in 3 and 7 wavy fins absorbers respectively.


  • New arrangements of the wavy fins structure were implemented on the absorber.
  • The wavy fins obstruct the flow on both passes of the double passes collector.
  • Thermal efficiency reached 84% with the new arrangements.


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