Deformation

NGSolve
1

I am attempting to deform a rectangle.
I expect the rectangle to enlarge in y-direction keeping its shape as a rectangle. How can I do it?

from numpy import *
from ngsolve import *
from netgen.occ import *
from ngsolve.webgui import Draw

Rect1 = MoveTo(-0.2, 0).Rectangle(0.15, 0.2).Face()
Rect1.bc('Rect1')
Rect2 = MoveTo(0.0, 0.0).Rectangle(0.15, 0.2).Face()
Rect2.bc('Rect2')
Rect2.maxh = 0.04
shape = Glue([Rect1, Rect2])

mesh = Mesh(OCCGeometry(shape, dim=2).GenerateMesh(maxh=0.05, quad_dominated=False))
fes = VectorH1(mesh, order=1)
gfu_history = GridFunction(fes, multidim=0)
gfu = GridFunction(fes)
dY = 0.4*sin(linspace(0, pi, 10))
for dy in dY:
	gfu.Set(CF((0, dy*y)), definedon=mesh.Materials('Rect2'))
	mesh.SetDeformation(gfu)
	gfu_history.AddMultiDimComponent(gfu.vec)
Draw(
    gfu_history,
    interpolate_multidim=True,
    animate=True,
    min=0,
    max=0.1,
    autoscale=False,
    deformation=True,
    settings={
        "camera": {"transformations": [{"type": "move", "dir": (0, 0, 1), "dist": -2}]}
    },
);

deformation

2

I chaged .Set to .Interpolate

for dy in dY:
	gfu.Interpolate(CF((0, dy*y)), definedon=mesh.Materials('Rect2'))
	mesh.SetDeformation(gfu)

Then I obtained what I wanted.