Investigation of air heating solar collector with energy concentrator

Abstract

The paper discusses the procedures of development and experimental investigation of the solar collector for air heating, using a solar energy concentrator. The collector consists of the solar energy concentrator, made of polished stainless sheets bent according to parabola with total aperture area 3.6 m2. In the focus of the concentrator a heat absorber tube assembled from specific form separate aluminium elements with a wall density 0.15 mm and painted in black tarnished colour is placed. The form of absorber elements is creating a turbulent air flow in the absorber tube, which increases the heat exchange through its wall. By a centrifugal ventilator the air flow of changeable intensity in the absorber tube has been created. The electric motor of the ventilator was fed by direct current produced by an amorphous silicon flexible photovoltaic module. On sunny September 11, 2015 day the efficiency of the collector was 73.7 %. The heated air temperature increment reached 57.3 ºC. Such air can be used for room heating or drying needs.