Royal IHC: Technology word of the month – Critical velocity

Royal IHC has just released a very interesting article named ‘Technology word of the month – Critical velocity’.

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A pipeline operators main concern is to prevent blockages. So how fast do we need to pump a slurry through a pipeline?

At high velocities slurry particles are in motion, typically by sliding or by being suspended in the water by turbulence.

At too low velocities particles stop moving.

“We call the velocity at this transition the “critical velocity”. In other industries, this velocity is often called the “deposition limit velocity”. If your pipeline velocity is below the critical velocity, the pipe may block,” said Royal IHC.

Many factors influence whether particles are in motion or not, like mixture velocity, pipe diameter, particle size and concentration.

Understanding how these nuances affect flow assurance is what Royal IHC pipeline designers and researchers work on every day.

An example: particles might be flowing in some parts of the pipe at high concentrations but stop moving at low concentrations in other parts in the pipeline.