Pipeline Stability Studies
PROSPER enables detailed pipeline stability studies to be carried out. This can be used for design purposes of new pipelines or to evaluate sizing of slug catchers, etc. for existing production system.
Slugging Calculations in PROSPER:
When steady-state flow occurs in a pipeline, time-averaged mass flow rate at the pipeline inlet and outlet are constant.
If slug flow occurs through this pipeline, gas and liquid rates and pressures are NOT constant: liquid slugs and following gas bubbles will vary in velocity and length.
A detailed description of the parameters used to describe the slug characteristics can be found below.
The slug model is assuming that the slug period includes:
- A gas bubble included within a liquid film
- A liquid slug containing small gas bubbles
The association of the gas bubble and the liquid slug forms the slug period.
The output variables that can be found in PROSPER are the following:
- Mean Slug Length and 1/1000 Mean Slug Length
- Mean Bubble Length and 1/1000 Mean Bubble Length
- Slug Liquid Rate and Slug Gas Rate
- Bubble Liquid Rate and Bubble Gas Rate
- Mean Slug Frequency and 1/1000 Slug Frequency:
- Slug Hold-up (HLS) and Equilibrium Hold-up (HLE):
- Slug Surge Factor (Liquid) and Slug Surge Factor (Gas)
- Bubble Surge Factor (Liquid) and Bubble Surge Factor (Gas)
The Taitel-Dukler flow map that is used in PROSPER to assess the extent of the slugging phenomenon in the system.
Pigging Calculations in PROSPER:
The gradient traverse calculations in PROSPER will include as well pigging calculations, which can be used to describe the pigging characteristics of the flow in pipelines.
The additional results reported in the gradient traverse results and related to the pigging calculations are pigged slug length, pigged slug volume, slug production time, slug residency time, time to produce pigged slug length and time for the pigged slug to reach the pipeline outlet.
