  The aim of this communication is to present a simplified, yet rigorous,
deduction of the Boussinesq approximated governing equations for buoyant flows.
In order to carry out the core deduction procedure, a simplified version of the
manifold asymptotic analyses available in the literature is discussed. The
method adopted in this study is focussed on the local balance equations valid
for a general, not necessarily Newtonian, fluid. The analysis is carried out by
demonstrating the leading order terms in the governing equations for the
asymptotic limit which characterises the approximation. The role played by the
effect of viscous dissipation is also taken into account.
