EURO 2025 Leeds
Abstract Submission

2029. Inverse Problem in River Hydraulics Solved via Derivative-Free Constrained Optimization

Invited abstract in session WA-35: Recent trends in zeroth order and simulation-based optimization: 2, stream Continuous and mixed-integer nonlinear programming: theory and algorithms.

Wednesday, 8:30-10:00
Room: Michael Sadler LG15

Authors (first author is the speaker)

1. Fabio Fortunato Filho
Department of Applied MathematicsIMECC, The State University of Campinas (UNICAMP)
2. José Mario Martínez
Dept. Applied Mathematics, University of Campinas

Abstract

The study investigates the application of the Augmented Lagrangian method to problems with differential equation constraints using derivative-free methods. In addition to the theoretical foundation, the research focuses on estimating the hydraulic coefficient in river flow modeling, a widely discussed problem in the literature. The channel modeling is based on the Saint-Venant equations, applied to the East Fork River, considering data collected over 31 days. To solve these equations, the finite difference method with artificial diffusion was employed, chosen for its computational efficiency, as the equations need to be solved repeatedly. Error minimization between observed and simulated data was performed using the derivative-free methods Nelder-Mead, PRIMA, and BOBYQA, considering a box-constrained problem. Since the selected quadratic methods are naturally suited for this type of problem, the Nelder-Mead approach included a penalty for out-of-box points. The results show that the proposed strategy is efficient and viable for all tested methods, reducing computational time and providing accurate estimates of the hydraulic coefficient. The study highlights the advantages of optimization over traditional methods and suggests future improvements, including compatibility with the HEC-RAS software, widely used for simulating flow in natural and artificial channels.

Keywords

Status: accepted

Back to the list of papers