1. n. [Drilling Fluids]
Ratio of the volume percent synthetic fluid to the volume percent water in a synthetic-base mud, where each is a percent of the total liquid in the mud. The SWR is calculated in an analogous way to the oil/brine ratio using data from the retort test.
Alternate Form: SWR
See: oil mud, syn, synthetic-base fluid, water, oil, and solids test