  We revisit a family of infinite-energy solutions of the 3D incompressible
Euler equations proposed by Gibbon et al. [9] and shown to blowup in finite
time by Constantin [6]. By adding a damping term to the momentum equation we
examine how the damping coefficient can arrest this blowup. Further, we show
that similar infinite-energy solutions of the inviscid 3D Boussinesq system
with damping can develop a singularity in finite time as long as the damping
effects are insufficient to arrest the (undamped) 3D Euler blowup in the
associated damped 3D Euler system.
