Thermo-economic assessment and optimization of a hybrid triple effect absorption chiller and compressor

Abstract

In this study, detailed thermo-economic analysis and parametric studies are conducted to evaluate the performance of a hybrid triple effect parallel flow water-lithium bromide (H2O-LiBr) absorption-compression cycle, that integrates a compressor between the evaporator and absorber. Optimization using a particle swarm optimization (PSO) algorithm is conducted to identify the optimum operating conditions of the system under various conditions. The results show that the effect of integrating the compressor on thermo-economic performance is different under various operating conditions. However, it significantly improves the coefficient of performance (COP) and the improvement decreases with a further increase in the compressor pressure ratio. Integrating the compressor makes the system operation practical under certain operating conditions, especially at high condenser temperatures, where a typical system fails to operate. The results show that employing the compressor is not always economically attractive and requires careful consideration. For an evaporator temperature of 6°C, a COP enhancement of over 200% can be achieved at a condenser temperature of 40°C, which corresponds to 57% reduction in the unit production cost of cooling. Performing a detailed optimization using a robust algorithm like PSO is very useful in designing a thermodynamically and economically efficient hybrid system.