Modeling and characterization of a tube-in-tube refrigerant cooled absorber.

Numéro : pap. n. 36

Auteurs : APRILE M., TOPPI T., GUERRA M., et al.

Résumé

A model for predicting the heat and mass transfer occurring inside a tube-in-tube counter current refrigerant cooled absorber (RCA) was developed. This particular heat exchanger has been used in a novel half-effect air cooled water ammonia chiller driven by low temperature heat (80°C), whose key operating principle consists in utilizing part of the liquid refrigerant leaving the condenser to cool the solution in which the remaining part of the refrigerant is absorbed after leaving the evaporator. During such operation, water-ammonia solution (with ammonia mass fraction about 0.55 – 0.65) at low pressure (4.5 - 5 bar) flows in the RCA annulus, counter-current with respect to the refrigerant (nearly pure ammonia at about 8 – 10 bar) flowing in the internal tube. Different simulation runs have been performed in order to explore the impact of different designs on the overall UA value and pressure drops. The model turned out to be very sensitive to the mass velocities of the two streams; an aspect that it is amplified by the mutual influence between annulus and tube heat transfer coefficients. The model predictions have been compared against a few experimental data which were observed during the test of the chiller prototype. Experimental data were found in reasonable agreement with simulation results.

Documents disponibles

Format PDF

Pages : 9 p.

Disponible

  • Prix public

    20 €

  • Prix membre*

    15 €

* meilleur tarif applicable selon le type d'adhésion (voir le détail des avantages des adhésions individuelles et collectives)

Détails

  • Titre original : Modeling and characterization of a tube-in-tube refrigerant cooled absorber.
  • Identifiant de la fiche : 30014328
  • Langues : Anglais
  • Source : International sorption heat pump conference (ISHPC2014), College Park, United States, March 31-April 2, 2014.
  • Date d'édition : 02/03/2014

Liens


Voir d'autres communications du même compte rendu (125)
Voir le compte rendu de la conférence