  This study presents an efficient, accurate, effective and unconditionally
stable time stepping scheme for the Darcy-Brinkman equations in
double-diffusive convection. The stabilization within the proposed method uses
the idea of stabilizing the curvature for velocity, temperature and
concentration equations. Accuracy in time is proven and the convergence results
for the fully discrete solutions of problem variables are given. Several
numerical examples including a convergence study are provided that support the
derived theoretical results and demonstrate the efficiency and the accuracy of
the method.
