Wellbore Volumetric Capacity (Vu)

The volumetric capacity of a wellbore is defined as the area that represents where the liquid level is rising defined as follows:

• Area of the annulus when the tubing is closed off, either by a valve or hydrostatic head in the tubing
• Area of the tubing when there is a packer isolating the annulus
• Area of the tubing and the annulus when the liquid level is rising in both

The value of the volumetric capacity typically varies from approximately 0.02 to 1 ft2 (0.002 to 0.1 m2), and is determined by the tubular configuration of the wellbore. It is used in non-conventional analyses (e.g., Slug, PITA, CCT) when there is a changing liquid level in the wellbore.