Abstract
A Secondary vorticity generated around large eddies in pure and forced plumes by the difference between the directions of the gravity acceleration and the density gradient was modelled and formulated using the Bjerknes theorem and the vorticity equation. As a result, it is found that the direction of secondary vorticity is the same as one of an original vorticity in the large eddy. In addition, the mechanism of turbulent entrainment of an environmental fluid was discussed connected with the secondary vorticity.
