Understanding Slug Flow Pattern Analysis — Lesson 3

This lesson covers the analysis of the slug flow pattern, focusing on the distortion and relative velocity in the pattern. It explains how the drift velocity U G j is a constant and how the velocity of the bubble can be taken as equal to the velocity of the gas in the slug flow pattern. The lesson also discusses the corrections needed under different flow circumstances, such as the wake effect of the preceding bubble and the effect of the bubble not moving relative to the average liquid velocity. It further explains how to generate a corrected expression of U d and how to calculate the void fraction and pressure gradient for the slug flow pattern. The lesson concludes with a discussion on the impact of long Taylor bubbles on the calculation of alpha and the pressure gradient.

Video Highlights

00:17 - Introduction to the distortion on the analysis of the slug flow pattern
09:45 - Discussion on the effect of the velocity profile on the bubble tip
16:51 - Discussion on the effect of the bubble size on the velocity and the pressure gradient
26:51 - Discussion on the effect of the bubble size on the pressure gradient in the horizontal slug flow
37:35 - Explanation of the concept of the bubble raise velocity in the slug flow pattern

Key Takeaways

- The drift velocity U G j in the slug flow pattern is a constant.
- The velocity of the bubble can be taken as equal to the velocity of the gas in the slug flow pattern.
- Corrections are needed under different flow circumstances, such as the wake effect of the preceding bubble and the effect of the bubble not moving relative to the average liquid velocity.
- A corrected expression of U d can be generated by introducing correction factors.
- The void fraction and pressure gradient for the slug flow pattern can be calculated.
- Long Taylor bubbles impact the calculation of alpha and the pressure gradient.