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update examples

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This commit is contained in:
Dario Coscia
2023-05-29 15:34:23 +02:00
committed by Nicola Demo
parent 37e9658211
commit eb531747e5
11 changed files with 331 additions and 216 deletions
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40
examples/problems/stokes.py
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@@ -5,36 +5,62 @@ from pina.problem import SpatialProblem
from pina.operators import nabla, grad, div
from pina import Condition, Span, LabelTensor
# ===================================================== #
# #
# This script implements the two dimensional #
# Stokes problem. The Stokes class is defined #
# inheriting from SpatialProblem. We denote: #
# ux --> field variable velocity along x #
# uy --> field variable velocity along y #
# p --> field variable pressure #
# x,y --> spatial variables #
# #
# ===================================================== #
class Stokes(SpatialProblem):
# assign output/ spatial variables
output_variables = ['ux', 'uy', 'p']
spatial_domain = Span({'x': [-2, 2], 'y': [-1, 1]})
# define the momentum equation
def momentum(input_, output_):
nabla_ = torch.hstack((LabelTensor(nabla(output_.extract(['ux']), input_), ['x']),
LabelTensor(nabla(output_.extract(['uy']), input_), ['y'])))
return - nabla_ + grad(output_.extract(['p']), input_)
# define the continuity equation
def continuity(input_, output_):
return div(output_.extract(['ux', 'uy']), input_)
# define the inlet velocity
def inlet(input_, output_):
value = 2 * (1 - input_.extract(['y'])**2)
return output_.extract(['ux']) - value
# define the outlet pressure
def outlet(input_, output_):
value = 0.0
return output_.extract(['p']) - value
# define the wall condition
def wall(input_, output_):
value = 0.0
return output_.extract(['ux', 'uy']) - value
# problem condition statement
conditions = {
'gamma_top': Condition(Span({'x': [-2, 2], 'y': 1}), wall),
'gamma_bot': Condition(Span({'x': [-2, 2], 'y': -1}), wall),
'gamma_out': Condition(Span({'x': 2, 'y': [-1, 1]}), outlet),
'gamma_in': Condition(Span({'x': -2, 'y': [-1, 1]}), inlet),
'D': Condition(Span({'x': [-2, 2], 'y': [-1, 1]}), [momentum, continuity]),
'gamma_top': Condition(location=Span({'x': [-2, 2], 'y': 1}), function=wall),
'gamma_bot': Condition(location=Span({'x': [-2, 2], 'y': -1}), function=wall),
'gamma_out': Condition(location=Span({'x': 2, 'y': [-1, 1]}), function=outlet),
'gamma_in': Condition(location=Span({'x': -2, 'y': [-1, 1]}), function=inlet),
'D1': Condition(location=Span({'x': [-2, 2], 'y': [-1, 1]}), function=momentum),
'D2': Condition(location=Span({'x': [-2, 2], 'y': [-1, 1]}), function=continuity),
}
# conditions = {
# 'gamma_top': Condition(location=Span({'x': [-2, 2], 'y': 1}), function=wall),
# 'gamma_bot': Condition(location=Span({'x': [-2, 2], 'y': -1}), function=wall),
# 'gamma_out': Condition(location=Span({'x': 2, 'y': [-1, 1]}), function=outlet),
# 'gamma_in': Condition(location=Span({'x': -2, 'y': [-1, 1]}), function=inlet),
# 'D': Condition(location=Span({'x': [-2, 2], 'y': [-1, 1]}), function=[momentum, continuity]),
# }