Annular Velocity

The annular velocity can be calculated using one of the following formulæ.

Or

Where:

• AV = annular velocity
• PO_bpm = pump output in bpm (barrels per minute) 1 barrel = 42 gallons
• PO_gpm = pump output in gpm (gallons per minute) 1 gallon = 0.0238095238 barrels
• ID2 = inside diameter of the wellbore or casing, squared
• OD2 = outside diameter of the drill pipe or tubing, squared
• 1029.4 = A conversion factor constant used to calculate the volume between the outside of a tube within the inside of another tube, using barrels.
• 24.5 = A conversion factor constant used to calculate the volume between the outside of a tube within the inside of another tube, using gallons.
• Pump Output = Refers to the measurement of the quantity of a fluid (to put that fluid in motion).