Document Type : Research Paper

Authors

Electromechanical Engineering Dept, University of Technology-Iraq, Alsina’a Street, 10066 Baghdad, Iraq.

Abstract

Window solar air collector is an imperative instrument for heating residential buildings in cold regions. This paper presents a numerical investigation of the thermal performance of a window solar air collector with seven moveable absorber plates. With glass on the front and back sides of the collector. By the use of FORTRAN 90; The three-dimensional steady-state turbulent forced convection method was used to solve the Navier-Stokes equations. The seven plates opened and closed at different angles in unison manually by a specific mechanical mechanism. The effect of changing the plate angles has been tested, alongside the effect of airflow rates and the intensity of solar radiation. Numerical results illustrate that air temperature difference is higher at vertical plates position (angle 0) compared to that at angle 90. In contrast, flexibility between sunlight penetrating the room and hot air from the collector will be gained when the plates are set on angle 90. Results indicate that the thermal performance was improved by 67% when the plates were set at angle 0. Maximum thermal efficiency for angle 0 was 72% at a mass flow rate of 0.0298 kg/s. However, maximum thermal efficiency was 51% at mass flow rate 0.0298 for angle 90°.

Graphical Abstract

Highlights

  • A new novel window with 7 movable absorber plates with different opening angles.
  • Best thermal performance and minimum of sunlight were obtained at angle 0.
  • Lower thermal performance and maximum of sunlight were obtained at angle 90.
  • A flexibility between hot air and sunlight requirements for angles between 0 and 90.

Keywords

Main Subjects

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