2. n. [Drilling Fluids]
A shorthand term for pressure, volume, temperature dependencies for fluid properties. In oil-base drilling fluids, PVT effects on viscosity and density must be understood to develop density and hydraulics programs. Downhole pressure makes the base oil more viscous and dense, whereas temperature has the opposite effect. Brines for downhole use also require an understanding of PVT behavior.
See related terms: brine, mud weight, rheology, viscosity