Two Phase Flow.- All of the discussion so far has been confined to single phase flow i. e. flow of either gas or liquid.
- There are situations in which are economically advantageous to transport both a gas and a liquid in a single pipeline simultaneously.
- This is called 2-phase flow.
- An example 2-phase flow involves certain off-shore oil operations,where it is extremely expensive to separate the liquid and gas phases in deep water.
- As the technology advances two-phase flow is likely to become common place in situations such as this.
- Two-phase flows may occur over a wide range of liquid to gas ratios and manifest a variety of flow patterns.
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| two phase flow patterns |
- Two phase flow technologies is much more complex than single-phase flow. However research suggest that the design of such systemsis possible.
- Experimental studies have revealed that2-phase-flow shows larger drops in pressure compared to single-phase flows.
- Two components of pressure drop are suggested in literature for 2-phase flows :
- The pressure drop due to friction which increases with increase in gas flow rate. This is the only component in horizontal lines.
- The pressure drop due to the head of liquid in inclined lines.Practically all of this pressure drop occurs in the uphill section of the pipeline.
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Iran-Turkmenistan pipeline
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source: Prof. Dr. O. Cahit ERALP
