Experimental investigation of optimum charging and discharging time on packed bed heat regenerator for space heating and solar drying application

Solar energy has outstanding potential as a renewable source of energy. Presented work deals with building of such heat storage system which can store heat radiated from sun during the day and provide space heating at night by gradually discharging it for space heating and solar drying application. A parametric experimental study has been carried out on the bases of numerical based equations for dry clay material filled in packed reservoir which act as porous bed for absorbing heat under four different temperature i.e. 40 °C, 45 °C, 50 °C, 55 °C and 3 diverse mass flow rate i.e. 0.225 kg/m2-s, 0.335 kg/m2-s and 0.445 kg/m2-s. Based on results the optimum charging time at 40 °C, 45 °C temperature range with optimum mass flow rate 0.445 kg/m2-s has been achieved 48 min and 55 min and optimum discharging time at 40 °C, 45 °C temperature range with optimum mass flow rate 0.225 kg/m2-s has been achieved 125 min and 130 min for space heating application. The optimum charging time at 50 °C, 55 °C temperature range with optimum mass flow rate 0.445 kg/m2-s has been achieved 62 min and 68 min and optimum discharging time at 50 °C, 55 °C temperature with optimum mass flow rate 0.225 kg/m2-s has been achieved 135 min and 140 min for solar drying application with at least 3 packed bed having bed length of 1.6 m and diameter 0.1 m, which satisfy the requirement of 8 hrs continuous heat supply through packed bed heat reservoir during night time for space heating and solar drying application.