Dynamic experimental analysis of a LiBr/H2O single effect absorption chiller with nominal capacity of 35 kW of cooling

Abstract

This paper examines the transient performance of a single effect absorption chiller which uses the LiBr/H2O pair with a nominal capacity of 35 kW. The goal of this study is to verify the absorption chiller when it is subjected to thermal loads and its capacity to respond transiently as a result of the temperature of the chilled, cold and hot water of the system. An experimental methodology was established in a microcogeneration laboratory to simulate the dynamic operating conditions of the system by considering the thermal load (chilled water), the activation source (hot water) and the heat dissipation circuit (cold water). The thermal load was simulated based on using a set of electrical resistors installed in a water heater and on activating the chiller from gas recovered from a 30 kW microturbine and by using a compact heat exchanger where the water is heated and sent in a hot water buffer tank where it was stored. The heat dissipation system of the absorption chiller consists of a pump and a cooling tower. The system responded appropriately to the thermal load imposed and provided coefficient of performance values in the transient regime of 0.55 to 0.70 for the temperature conditions tested.