Performance evaluation of a continuous operation adsorption chiller powered by solar energy using silica gel and water as the working pair

Abstract

In the present study, dynamic analysis and performance evaluation of a solar-powered continuous operation adsorption chiller are introduced. The adsorption chiller uses silica gel and water as the working pair. The developed mathematical model represents the heat and mass transfer within the reactor coupled with the energy balance of the collector plate and the glass cover. Moreover, a non-equilibrium adsorption kinetic model is taken into account by using the linear driving force equation. The variation of solar radiation, wind speed, and atmospheric temperature along a complete cycle are considered for a more realistic simulation. Based on the case studied and the baseline parameters, the chiller is found to acquire a coefficient of performance of 0.402. The average thermal efficiency of the solar collector is estimated to be 62.96% and the average total efficiency approaches a value of 50.91%. Other performance parameters obtained are 363.8 W and 1.82 W/kg for the cooling capacity and the specific cooling power of the chiller, respectively. Furthermore, every 1 kg of silica gel inside the adsorption reactor produces a daily chilled water mass of 3 kg at a temperature of 10 °C. In addition, the cooling system harnesses 25.35% of the total available solar radiation and converts it to a cooling effect.