The essence of the SIMPLE method lies in its coupling between the mome
ntum and continuity equations. Almost all the algorithms of the SIMPLE
family are based on one precondition, that is, the corrected velocity
is obtained from the corrected pressure only. However, in buoyancy-dr
iven flows, there are two major factors driving the fluid movement: th
e temperature gradients and the pressure (including kinetic pressure)
gradients. In this article, the effect of the temperature correction o
n the velocity correction is considered during the derivation of the p
ressure-linked equation. A modification to the SIMPLE algorithm, SIMPL
ET, is proposed and two cases are tested. It is shown that this modifi
cation provides a better convergence rate and more robust results.