  In this paper we propose and analyze a uniformly robust staggered DG method
for the unsteady Darcy-Forchheimer-Brinkman problem. Our formulation is based
on velocity gradient-velocity-pressure and the resulting scheme can be flexibly
applied to fairly general polygonal meshes. We relax the tangential continuity
for velocity, which is the key ingredient in achieving the uniform robustness.
We present well-posedness and error analysis for both the semi-discrete scheme
and the fully discrete scheme, and the theories indicate that the error
estimates for velocity are independent of pressure. Several numerical
experiments are presented to confirm the theoretical findings.
