EFFECT OF THERMAL STORAGE ON THE PERFORMANCE OF AN AIR COLLECTOR - A PERIODIC ANALYSIS

This communication presents parametric studies of an air collector con sisting of different thermal energy storage materials (concrete, brick , sand, ground, phase change material (PCM)) on top, but with soil pro vided at the bottom. The effect of storage material, optimization of l ength and thickness of Storage material, and the effect of flow rate o n outlet air temperature, useful energy gain and daily efficiency is r eported. Numerical computations have been carried out for a typical da y in the month of June for Delhi climatic conditions. It is observed t hat there is a significant phase shift (10-12 h) owing to the storage effect. The hourly maximum useful energy gain decreases with the fract ion of storage material thickness, whereas the minimum amount increase s and approaches the maximum value. (C) 1997 Elsevier Science Ltd.