Dynamic simulation of an air-cooled LiBr-H2O absorption chiller based on variable heat and mass transfer coefficients.

Number: AB-SI1-1133

Author(s) : FARNOS J., PAPAKOKKINOS G., CASTRO J., et al.

Summary

The paper describes the numerical simulation of a direct air-cooled single-effect absorption chiller and validates the obtained results by means of experimental data obtained from an own-designed and commissioned small capacity absorption chiller. For performing numerical simulations, a modular object-oriented simulation platform is used (NEST platform tool), which allows the linking between different components (pump, valves, heat exchangers, etc.). A lumped parametric dynamic model based on mass, momentum and energy balances, applied to the internal components of the absorption machine (absorber, generator, condenser, evaporator and solution heat exchanger) has been implemented. Thermal and mass storage in each one of the components are
taken into account in the transient evaluation and pressure losses in the solution heat exchanger are evaluated by means of a pressure drop coefficient. The model depends on heat and mass transfer coefficients, which have been implemented depending on basic empirical correlations, and are calculated in nested subroutines of the dynamic simulation. The aim of this paper is to improve the available numerical modeling approach that is able to simulate the chiller under transient conditions by taking advantage of previous experiences in falling film heat exchangers. As a first step the model is validated against the results of a previous laboratory prototype. Finally, the performance of a prototype demonstration 7 kW air-cooled LiBr-H2O absorption chiller is calculated and studied under transient conditions.

Details

  • Original title: Dynamic simulation of an air-cooled LiBr-H2O absorption chiller based on variable heat and mass transfer coefficients.
  • Record ID : 30022717
  • Languages: English
  • Source: International sorption heat pump conference, ISHPC 2017, Tokyo august 7-10.
  • Publication date: 2017/08/07

Links


See other articles from the proceedings (159)
See the conference proceedings