Partager

Document IIF

Étalonnage et validation d'un modèle modifié d'ébullition en conditions de non-équilibre pour l'écoulement transcritique instantané dans des buses diphasiques au R744

Calibration and validation of a modified non-equilibrium boiling model for transcritical flashing flow in two-phase R744 nozzles.

Auteurs : LONG J., YU B., WANG D., SHI J., CHEN J.

Type d'article : Article de la RIF

Résumé

A modified homogeneous non-equilibrium boiling approach (HNB) was proposed for high-fidelity modelling of the trans-critical flashing process in two-phase R744 ejector nozzles. In the modified approach, the method of determining the metastable liquid saturation pressure was improved by integrating the metastable liquid enthalpy. Experimental tests were conducted on two different nozzles to calibrate the lumped accommodation coefficient in the modified HNB. The calibration dataset consisted of 30 trans-critical test points, with the motive inlet pressure ranging from 7.5 MPa to 11.5 MPa and temperature varying from 21 °C to 45 °C. It was demonstrated that the boiling coefficient was strongly related to nozzle inlet pressure and specific enthalpy. The coefficient was therefore fitted as a function of the operating condition. The modified HNB with the fitted function was then validated against another set of test data composed of 29 test points. The results demonstrated that the relative errors of the nozzle mass-flow rates were within 3 %. Finally, the modified HNB with the improved metastable liquid saturation pressure was compared and discussed with the existing HNB approach in the literature.

Documents disponibles

Format PDF

Pages : 97-110

Disponible

  • Prix public

    20 €

  • Prix membre*

    Gratuit

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

Détails

  • Titre original : Calibration and validation of a modified non-equilibrium boiling model for transcritical flashing flow in two-phase R744 nozzles.
  • Identifiant de la fiche : 30032456
  • Langues : Anglais
  • Sujet : Technologie
  • Source : International Journal of Refrigeration - Revue Internationale du Froid - vol. 165
  • Date d'édition : 09/2024
  • DOI : http://dx.doi.org/10.1016/j.ijrefrig.2024.06.018

Liens


Voir d'autres articles du même numéro (39)
Voir la source

Indexation