The transition of a thermal plume from laminar to turbulent flow is characterized by a non-axisymmetric deformation. Past analyses are limited either to the planar plume or to the axisymmetrie assumption, and subsequently are not capable of predicting the real phenomenon. The present study develops a new dispersion equation which accounts for the instability of all transverse modes on the plume. The dispersion equation shows that the dynamic interaction of the ambient air is responsible for the growth of any disturbance on the plume surface, and the sinuous mode has the highest growth rate at all wavenumbers when the density difference between the plume and the surrounding air is small. The present theory proves the snake form of onset instability of a plume. © 1992.
Yang, H. Q. (1992). Buckling of a thermal plume. International Journal of Heat and Mass Transfer, 35(6), 1527–1532. https://doi.org/10.1016/0017-9310(92)90042-Q