How to add a drag term to the Navier-Stokes equations and find the velocity derivative with respect to this term

XavierLucas · December 24, 2025, 6:19am

examples/cfd/ldc_pinns/train.py

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import hydra
import matplotlib.pyplot as plt
import numpy as np
import torch

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The link is the example that solves the lid driven cavity based on PINN. But I want to add a drag term of (-alpha*u, -alpha*v) to the Navier-Stokes equations. After training, find the velocity derivative with respect to alpha. Could anyone help me? Thank you very much.

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How to add a drag term to the Navier-Stokes equations and find the velocity derivative with respect to this term

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