Effects of turbulence models on forced convection subcooled boiling in vertical pipe. (June 2015)

• Record Type: Journal Article
• Authors: Zhang, Rui; Cong, Tenglong; Tian, Wenxi; Qiu, Suizheng; Su, Guanghui
• Is Part Of: Annals of nuclear energy. Volume 80(2015:Jun.)
• Page Start: 293
• Page End: 302
• Publication Date: 2015-06
• Subjects: Subcooled boiling -- Turbulence model -- Wall function; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2015.01.039
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: Subcooled boiling phenomena are simulated by FLUENT code. Capacities of turbulence model, wall function and two-phase treatment are studied. k – ε models perform better than k – w models for predicting subcooled boiling. Grid with Y + near to 1 could not give good results though k – w models are used. Abstract: In this study, a two-fluid model coupled with wall boiling model was adopted to investigate two-phase forced convection subcooled boiling process in a vertical heated pipe based on FLUENT 14.5. The influences of turbulence models ( k – ε models and k – w models) on flow and heat transfer in pipe were studied. The performances of different turbulent models, wall functions and two-phase turbulence treatments were analyzed based on four sets of grids by comparing the calculated results with Bartolemei experimental data. The results of k – ε models showed better agreement with experimental data than these of k – w models. The Dispersed and Per Phase treatments for two-phase turbulence parameters performed no better than the Mixture treatment. The enhanced wall function could not cope the situation for grid with near-wall Y -plus near to 1. k – ε models with appropriate mesh size performed excellent in predicting subcooled boiling in vertical channel. This work can be referred for choosing turbulence model when analyzing subcooled boiling by CFD methodology.