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Neural network-based methods have demonstrated effectiveness in solving high-dimensional Mean-Field Games (MFG) equilibria, yet ensuring mathematically consistent density-coupled evolution remains a major challenge. This paper proposes the…

Machine Learning · Computer Science 2025-03-11 Jinwei Liu , Lu Ren , Wang Yao , Xiao Zhang

One of the challenges when simulating astrophysical flows with self-gravity is to compute the gravitational forces. In contrast to the hyperbolic hydrodynamic equations, the gravity field is described by an elliptic Poisson equation. We…

Numerical Analysis · Mathematics 2021-06-30 Michael Schlottke-Lakemper , Andrew R. Winters , Hendrik Ranocha , Gregor J. Gassner

The goal of this report is to present the final project conducted in order to fulfill the requirements of the M.Sc. degree at the Department of Mechanical Engineering, Ben-Gurion University (BGU) of the Negev. The project comprises…

Fluid Dynamics · Physics 2022-12-29 Dmitry Zviaga

Recently, there has been a great interest in analysing dynamical flows, where the stationary limit is the minimiser of a convex energy. Particular flows of great interest have been continuous limits of Nesterov's algorithm and the Fast…

Optimization and Control · Mathematics 2021-06-29 Radu Boţ , Guozhi Dong , Peter Elbau , Otmar Scherzer

Heat-flux boundary conditions are challenging to implement efficiently in rarefied gas flow simulations because the wall-reflected gas temperature and density must be determined dynamically during the computation. This paper aims to tackle…

Computational Physics · Physics 2026-01-21 Yanbing Zhang , Ruifeng Yuan , Liyan Luo , Lei Wu

We are concerned with the simulation and optimization of large-scale gas pipeline systems in an error-controlled environment. The gas flow dynamics is locally approximated by sufficiently accurate physical models taken from a hierarchy of…

Optimization and Control · Mathematics 2021-11-10 Pia Domschke , Oliver Kolb , Jens Lang

The DC Optimal Power Flow (DC-OPF) problem is fundamental to power system operations, requiring rapid solutions for real-time grid management. While traditional optimization solvers provide optimal solutions, their computational cost…

Machine Learning · Computer Science 2025-12-15 Kshitiz Khanal

We present an efficient discontinuous Galerkin scheme for simulation of the incompressible Navier-Stokes equations including laminar and turbulent flow. We consider a semi-explicit high-order velocity-correction method for time integration…

Numerical Analysis · Mathematics 2017-08-15 Benjamin Krank , Niklas Fehn , Wolfgang A. Wall , Martin Kronbichler

AC optimal power flow (AC~OPF) is a challenging non-convex optimization problem that plays a crucial role in power system operation and control. Recently developed convex relaxation techniques provide new insights regarding the global…

Optimization and Control · Mathematics 2018-04-10 Mohammad Rasoul Narimani , Daniel K. Molzahn , Mariesa L. Crow

The gas-kinetic scheme(GKS) is a promising computational fluid dynamics (CFD) method for solving the Navier-Stokes equations. It is based on the analytical solution of the BGK equation, which enables accurate and robust simulations. While…

Fluid Dynamics · Physics 2025-08-12 Yue Zhang , Xing Ji , Kun Xu

The DC optimal power flow (DCOPF) problem is a fundamental problem in power systems operations and planning. With high penetration of uncertain renewable resources in power systems, DCOPF needs to be solved repeatedly for a large amount of…

Systems and Control · Electrical Eng. & Systems 2020-09-22 Ling Zhang , Yize Chen , Baosen Zhang

Computational speed and global optimality are key needs for practical algorithms for the optimal power flow problem. Two convex relaxations offer a favorable trade-off between the standard second-order cone and the standard semidefinite…

Optimization and Control · Mathematics 2021-12-23 Christian Bingane , Miguel F. Anjos , Sébastien Le Digabel

Power flow analysis is a fundamental tool for power system analysis, planning, and operational control. Traditional Newton-Raphson methods suffer from limitations such as initial value sensitivity and low efficiency in batch computation,…

Systems and Control · Electrical Eng. & Systems 2025-12-02 Xuezhi Liu

Despite its numerical challenges, finite element method is used to compute viscous fluid flow. A consensus on the cause of numerical problems has been reached; however, general algorithms---allowing a robust and accurate simulation for any…

Computational Engineering, Finance, and Science · Computer Science 2019-02-05 Bilen Emek Abali

Solving the Alternating Current Optimal Power Flow (AC OPF) problem to global optimality remains challenging due to its nonconvex quadratic constraints. In this paper, we present a unified framework that combines static piecewise…

Optimization and Control · Mathematics 2025-06-17 Yu-Yang Tang , Liang Chen , Sheng-Jie Chen , Yu-Hong Dai , Bo Zhou , Xiaomeng Ai

The Gas-Kinetic Scheme (GKS), widely used in computational fluid dynamics for simulating hypersonic and other complicated flow phenomena, is extended in this work to electromagnetic problems by solving Maxwell's equations. In contrast to…

Numerical Analysis · Mathematics 2026-01-01 Zhigang Pu , Wenpei Long , Kun Xu

We describe compressible two-phase flows by a single-velocity six-equation flow model, which is composed of the phasic mass and total energy equations, one volume fraction equation, and the mixture momentum equation. The model contains…

Fluid Dynamics · Physics 2021-08-03 Marica Pelanti

An optimization problem considering AC power flow constraints and integer decision variables can usually be posed as a mixed-integer quadratically constrained quadratic program (MIQCQP) problem. In this paper, first, a set of valid linear…

Optimization and Control · Mathematics 2015-09-18 Qifeng Li

This paper presents a reformulation for the automatic generation control (AGC) in a decomposed convex relaxation algorithm. It finds an optimal solution to the AC optimal power flow (ACOPF) problem that is secure against a large set of…

Optimization and Control · Mathematics 2021-07-09 Muhammad Waseem , Saeed D. Manshadi

Direct-current microgrids (DC-MGs) can operate in either grid-connected or stand-alone mode. In particular, stand-alone DC-MG has many distinct applications. However, the optimal power flow problem of a stand-alone DC-MG is inherently…

Optimization and Control · Mathematics 2017-08-18 Jia Li , Feng Liu , Zhaojian Wang , Steven H Low , Shengwei Mei