الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 244 |  |  |
| | | from | 244 | | |
Abstract
Most of various models available for the analysis of two-phase up-flows in circular pipes are one-dimensional and are based mainly on a combination of empirical correlations .A procedure has been previously proposed by others which is able to predict the velocity and void fraction fields of bubble flows. Although in the previous work a comparison have been made between the predicted and experimental velocity distribution, but most of them failed in predicting the exact void fraction profile, neither in magnitude nore in trend, especially, the peaking in void fraction which has been recorded experimentally, in the near wall region. The main objective of the present work is therefore, to investigate the reasons that causes the disparity in the predicted void fraction and to try to accomplish better agreement between the predicted and the experimental profiles, and also to test the validity of the turbulence model, turbulence correlation and turbulence averaging technique used in the numerical procedure.In the method employed separate conservation equations are formulated for the liquid phase in conjunction with similar simplified equations for the gas phase.