Effect of latent storage geometry on stratification in domestic solar water heater

摘要

The present work finds the influence of energy storage geometry to enhance stratification in a domestic solar water heater. The geometric configuration of energy storage attached to the crest of the solar domestic water heater tank affects the operation through upgraded stratification. Phase Change Material (PCM) was used as energy storage material. Three types of energy storage geometry of same volume of different dimensions were used in the study, those were a cylinder, circular fins around the cylinder, and spiral. Paraffin wax was used as PCM. Heating and cooling tests have been conducted in a typical domestic solar water heater with flat plate collector under conventional operating atmosphere. Eventually the temperature distribution over the altitude of the storage tank, charging energy efficiency, stratification number and MIX number has been studied for the three cases. Spiral energy storage geometry produces desirable outcomes of the stratification of the tank.