Document IIF

Effet de l'ajout de lubrifiant sur le mouvement des bulles du frigorigène CO2 dans le processus d'ébullition nucléée.

Effect of lubricant addition on bubble motion of refrigerant CO2 in the nucleate boiling process.

Auteurs : HUANG Y., XU X., LI X., LIU X., LIU C.

Type d'article : Article de la RIF

Résumé

In this study, the influence mechanism of lubricating oil on the heat transfer of CO2 flow boiling was investigated from a mesoscopic perspective. A multiphase and multicomponent lattice Boltzmann model was proposed to simulate the rising motion of CO2 bubbles in CO2 with a small amount of lubricating oil based on the pseudopotential model. There are few simulations of multicomponent with different chemical compositions in existing studies. Moreover, the original pseudopotential model exhibited increasing instabilities at higher viscosity ratios. The model proposed in this study realized the mesoscopic simulation of a CO2/lubricant system by using an explicit forcing model to achieve numerical calculation under a high viscosity ratio and solve the evolution of the number density of each component to obtain the evolution of the macro parameters. The effectiveness of the model was verified using a Laplace's law simulation. Based on this model, the rising motions of single bubbles, double bubbles, and bubble groups under different oil concentrations were simulated. The effects of the lubricant on the rising velocity, morphology, and interaction of bubbles during bubble motion were analyzed in detail. The numerical results indicated that the variations in bubble shape decreased and drag force increased with the addition of oil. At an oil concentration of 0.05, the drag coefficient was 1.14 times higher than that under the oil-free condition. In addition, the presence of oil weakened the flow field disturbance caused by bubble interactions and resulted in the suppression for nucleate boiling.

Documents disponibles

Format PDF

Pages : 104-112

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 : Effect of lubricant addition on bubble motion of refrigerant CO2 in the nucleate boiling process.
  • Identifiant de la fiche : 30029835
  • Langues : Anglais
  • Sujet : Technologie
  • Source : International Journal of Refrigeration - Revue Internationale du Froid - vol. 139
  • Date d'édition : 07/2022
  • DOI : http://dx.doi.org/10.1016/j.ijrefrig.2022.03.030

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