Доступ предоставлен для: Guest

ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

THE EFFECT OF FREE CONVECTION ON PLUG FORMATION DURING CRYOGENIC PIPE-FREEZING : A NUMERICAL STUDY

Get access (open in a dialog) DOI: 10.1615/IHTC10.1600
pages 55-60

Аннотация

A numerical model was developed in order to investigate the effect of convection on freezing during cryogenic pipe freezing in a vertical pipe. In order to simulate an infinite length of pipe, flow was allowed across the bottom boundary of the numerical domain. The temperature of the water entering the domain was kept fixed at the initial water temperature and the interaction between the flow and the forming plug was predicted. The developing plug was found to distort the convection cell, causing the regions above and below the plug neck to become more and more isolated as the plug developed. Cooled water was trapped above the neck and the bulk of the relatively warm water entering the domain was turned at the plug neck, maintaining the temperature of the region below the plug neck. When the temperature and velocities were significantly large, the ice formation in the region below the neck was retarded, causing the position of the neck to move up the plug.
The results obtained in this investigation were limited by the simplifications made in formulating the velocity boundary condition. However, the predicted plug profiles resembled those measured during experiments and therefore the results can be considered as giving a qualitative description of the processes involved during freezing in a vertical pipe.