The influence of bubble departure characteristics on CHF prediction at high-pressure conditions

• Main Authors: Sai Raja Gopal Vadlamudi, Arun K. Nayak
• Format: Article
• Language: English
• Published: Elsevier 2020-12-01
• Series: Case Studies in Thermal Engineering
• Subjects: CHF prediction; Subcooled boiling modeling; Critical heat flux; CFD modeling; Bubble departure diameter prediction
• Online Access: http://www.sciencedirect.com/science/article/pii/S2214157X20304779

The two-fluid Eulerian model, coupled with the heat flux partitioning model, is being widely used to predict subcooled flow boiling characteristics and critical heat flux (CHF). The heat flux partitioning model relies on essential parameters like bubble departure diameter, departure frequency, and nucleation site density. Mainly, performing experiments to determine bubble departure diameters and frequencies is challenging. Another approach is to use semi-mechanistic models; however, even such models rely on some crucial parameters like advancing contact angle, receding contact angle, contact diameter, and many others. In this study, the influence of such parameters, and the role of different forces in determining bubble departure diameters and departure frequencies, at high-pressure conditions is studied. Moreover, a parametric analysis is carried to understand the influence of such parameters on CHF prediction.