Subglacial current with constant viscous wall layers
= Subglacial current with constant viscous wall layers
{title2=$D=\rho_wg\delta_v/(2\mu)$}
In a water layer confined between horizontal rock and a movable constant-pressure ice roof, <hydrostatic pressure> and two wall stresses $\mu u/\delta_v$ give $u=-Dh h_x$, $q=-Dh^2h_x$ and $h_t=D(h^2h_x)_x$, with $D=\rho_wg\delta_v/(2\mu)>0$. This closure uses a constant <viscous boundary layer> thickness, not a generic quadratic turbulent drag law.