Effect of Air Gap Width on the Evaluation of the Trombe Wall Efficiency

Abstract

This study examines the selection of the best air gap to a model solar passive solar system chosen for heating in a cold climate based on instantaneous efficiency. The experiments have been performed on a passive solar system, which has been constructed from insulation sandwich panels in all sides except the south facade, which has been built from insulation sandwich panels on all sides except the south facade, where Trombe wall has been built in it, which is constructed from reinforced concrete and their exterior surface has been painted with dark black color, and covered with a single transparent glass layer. Five sets of experiments have been performed on the test system by changing the width of the air gap from 30 to 10 cm under the weather conditions in January 2017 in the city of Kirkuk (Iraq). The experimental results have showed that the 33 to 36% of the absorbs energy by Trombe wall has been converted to instantaneous energy provided to the heating space during the day. In addition, the results of the energy analysis of experimental equations have been produced to assess the efficiency of the system; they show that the 15 cm air gap has a better case when applying the same parameters, this result is consistent with an experimental study conducted by R. L. Casperson and C. J. Hocever, 1979.