Abstract
In flooded evaporators, refrigerants are boiling outside the tubes. This paper focuses on the bubbly two-phase flow characteristics in twisted tube bundles. The quasi 3-D high speed video method and computational fluid dynamics are carried out to understand the effects which angles between the major axis of the cylinder and vertical direction ( ) and bubble diameters have on the motion behaviours of bubbly flow. is adjusted to 0°, 30°, 45° and 60°，respectively. Bubble diameter is 4mm, 6mm and 8mm, respectively. The turbulence intensity of fluid outside the tubes which is resulted by bubble rising behaviour is also investigated. The results show that the elliptical cylinders with different s lead to bubble sliding out the surface of tubes, rising steadily and spreading widely in tube bundles. And larger bubbles have a stronger effect on turbulence intensity of liquid phase flow. It also can be concluded that the surface geometry of twisted tube plays an active role in heat transfer enhancement of the twisted tube evaporator
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
