On Plume Rise—Matching Daysmoke With Briggs Equations for Industrial Stacks

The Briggs Equations for plume rise from industrial and power plant stacks have been extensively validated with stack plume observations. Daysmoke, a plume rise model developed for the simulation of smoke plumes from prescribed burns, was matched with the Briggs Equations for a wide range of plume diameters and for stack-level wind speeds ranging from 2.5 m sec-1 to 10 m sec-1. Daysmoke plumes match Briggs plume centerlines almost perfectly when Daysmoke entrainment coefficients are adjusted for the degree of plume “bentoverness” and wind speed. The results show that Daysmoke obeys the so-called 2/3 law for plume rise even though the 2/3 law is not explicitly formulated in Daysmoke.