Unlink the laminar gradient pointers
subroutine destroy_laminar_grad()
!< Unlink the laminar gradient pointers
implicit none
DebugCall('destroy_laminar_grad')
nullify(gradu_x)
nullify(gradv_x)
nullify(gradw_x)
nullify(gradT_x)
nullify(gradu_y)
nullify(gradv_y)
nullify(gradw_y)
nullify(gradT_y)
nullify(gradu_z)
nullify(gradv_z)
nullify(gradw_z)
nullify(gradT_z)
end subroutine destroy_laminar_grad