Preliminary evaluation of a pre-industrial air-cooled LiBr-H2O small capacity absorption machine

The paper describes the thermal design, and evaluates the preliminary operational results of a small capacity pre-industrial LiBr-H2O air-cooled absorption machine in order to validate a numerical model and apply it to simulate a new 7kW LiBr-H2O air-cooled absorption chiller, conceived for low temperature driven, solar cooling or wasted heat. This numerical model is able to simulate the dynamical thermohydraulic behavior of a single-effect absorption machine in transient conditions, being implemented using a NEST platform (object-oriented numerical tool). The analysis of the absorption machine interaction with the other components of a solar cooling facility is also enhanced. Numerical results are obtained and the validation tested. From the simulation it is possible to redefine regulation and control strategies in order to optimize the operation of the absorption chiller. Finally, based on the numerical simulation results, improvements on the set-up of a new 7kW prototype are addressed.