To rephrase that:

The 2D function: phis(x,y) should become

a 3D function: phis_extended(x,y,z) independent of z, i.e.,

its value does not vary in the z-direction but can vary in the horizontal and time.

How does one do that in FD?

From: firedrake-bounces@imperial.ac.uk <firedrake-bounces@imperial.ac.uk> on behalf of Floriane Gidel [RPG] <mmfg@leeds.ac.uk>
Sent: Thursday, December 10, 2015 4:53 PM
To: firedrake@imperial.ac.uk
Subject: [firedrake] 2D to 3D function

Dear all,

First of all, thanks a lot for your time last Friday, and your help both for the implementation and for the installation of Firedrake.

I am now trying to implement the equations we discussed on Friday, for the 3D potential flow equations. As a reminder, I solve the equations for phi, h, but also phi_s which is a 3D function, but is only updated at the free surface. However, I would like to update the interior nodes of phi_s as well, by copying the value of its surface nodes, as soon as they are updated (that is, simultaneously with solving the coupled equations). Is there a way to do this?

I attach a short pdf summarising the equations, the current implementation and the issue I get.

Thank you very much,

Floriane