This paper investigates an experimental study of heat transfer and efficiency of solar heater of air through poly absorber plate. The important of solar heater application gives benefit for space heating and dryer. The increase of surface area in heater plate improves the thermal efficiency and their variable. The forced convection of heat transfer coefficient and rate is studied by various flow characteristics of air via combination of three stage plate surface. The dimensionless character of Reynolds number is formulated to study the laminar and turbulent flow of air through proposed air heater to improve the thermal behavior of heating application. The laminar characteristic is observed in the region of flat plate surface (Stage I) to stabilize the flow at initial. The curved surface plate (Stage II) is now change the flow pattern as turbulent and then passes through the holed flat surface plate (Stage III) to the outlet duct. The observed variable are inlet/ ambient & outlet of air temperature, average of three stage plate surface temperature, velocity of air at outlet and solar radiation. These variables are performed at different Reynolds number using Data Logger Unit (DLU) and C++ coding. The experimental investigation of proposed design gives better thermal efficiency and their variable compare to corrugation plate Solar Air Heater (SAH). The increase in surface area and speed of flow is investigating the better thermal behavior of the system.
