English
Related papers

Related papers: Data assimilation for slightly compressible flow

200 papers

Most fluid flow problems that are vital in engineering applications involve at least one of the following features: turbulence, shocks, and/or material interfaces. While seemingly different phenomena, these flows all share continuous…

Fluid Dynamics · Physics 2019-01-01 Bahman Aboulhasanzadeh , Kamran Mohseni

Data assimilation (DA) aims to estimate the full state of a dynamical system by combining partial and noisy observations with a prior model forecast, commonly referred to as the background. In atmospheric applications, this problem is…

Atmospheric and Oceanic Physics · Physics 2025-05-29 Jing-An Sun , Hang Fan , Junchao Gong , Ben Fei , Kun Chen , Fenghua Ling , Wenlong Zhang , Wanghan Xu , Li Yan , Pierre Gentine , Lei Bai

Fluids can behave in a highly irregular, turbulent way. It has long been realised that, therefore, some weak notion of solution is required when studying the fundamental partial differential equations of fluid dynamics, such as the…

Analysis of PDEs · Mathematics 2023-06-14 Dennis Gallenmüller , Raphael Wagner , Emil Wiedemann

Data assimilation (DA) improves prediction of chaotic systems by combining model forecasts with sparse, noisy observations. Many DA methods are inherently probabilistic, but accurate probabilistic DA is often computationally expensive…

Fluid Dynamics · Physics 2026-04-24 Aditya Sai Pranith Ayapilla , Kazuya Miyashita , Yuki Yasuda , Ryo Onishi

Understanding and predicting people flow in urban areas is useful for decision-making in urban planning and marketing strategies. Traditional methods for understanding people flow can be divided into measurement-based approaches and…

Human-Computer Interaction · Computer Science 2024-01-18 Ryo Murata , Kenji Tanaka

Developing robust data assimilation methods for hyperbolic conservation laws is a challenging subject. Those PDEs indeed show no dissipation effects and the input of additional information in the model equations may introduce errors that…

Optimization and Control · Mathematics 2015-03-27 Anne-Céline Boulanger , Philippe Moireau , Benoit Perthame , Jacques Sainte-Marie

We consider a multi-dimensional model of a compressible fluid in a bounded domain. We want to estimate the density and velocity of the fluid, based on the observations for only velocity. We build an observer exploiting the symmetries of the…

Optimization and Control · Mathematics 2016-11-24 Amit Apte , Didier Auroux , Mythily Ramaswamy

Analyzing large-scale data from simulations of turbulent flows is memory intensive, requiring significant resources. This major challenge highlights the need for data compression techniques. In this study, we apply a physics-informed Deep…

Fluid Dynamics · Physics 2022-07-26 Mohammadreza Momenifar , Enmao Diao , Vahid Tarokh , Andrew D. Bragg

There has been a recent surge in development of accurate machine learning (ML) weather prediction models, but evaluation of these models has mainly been focused on medium-range forecasts, not their performance in cycling data assimilation…

Atmospheric and Oceanic Physics · Physics 2024-12-25 Laura C. Slivinski , Jeffrey S. Whitaker , Sergey Frolov , Timothy A. Smith , Niraj Agarwal

In this paper we propose a new sequential data assimilation method for non-linear ordinary differential equations with compact state space. The method is designed so that the Lyapunov exponents of the corresponding estimation error dynamics…

Dynamical Systems · Mathematics 2017-11-15 Jason Frank , Sergiy Zhuk

In this article, we provide a methodology to reconstruct high-Reynolds number turbulent mean-flows from few time-averaged measurements. A turbulent flow over a backward-facing step at Re = 28275 is considered to illustrate the potential of…

Fluid Dynamics · Physics 2020-09-23 Lucas Franceschini , Denis Sipp , Olivier Marquet

Data assimilation is the process to fuse information from priors, observations of nature, and numerical models, in order to obtain best estimates of the parameters or state of a physical system of interest. Presence of large errors in some…

Numerical Analysis · Mathematics 2015-11-06 Vishwas Rao , Adrian Sandu , Michael Ng , Elias Nino-Ruiz

A novel thermodynamically consistent diffuse interface model is derived for compressible electrolytes with phase transitions. The fluid mixtures may consist of N constituents with the phases liquid and vapor, where both phases may coexist.…

Analysis of PDEs · Mathematics 2014-11-13 Wolfgang Dreyer , Jan Giesselmann , Christiane Kraus

This article develops a general framework for continuous deterministic data assimilation for semilinear parabolic equations by means of evolution equations. Introducing a nudged model driven by partial observations, the global…

Analysis of PDEs · Mathematics 2026-02-25 Gianmarco Del Sarto , Matthias Hieber , Filippo Palma , Tarek Zöchling

A consistent kinetic modeling and discretization strategy for compressible flows across all Prandtl numbers and specific heat ratios is developed using the quasi-equilibrium approach within two of the most widely used double-distribution…

Fluid Dynamics · Physics 2026-03-17 R. M. Strässle , S. A. Hosseini , I. V. Karlin

Using a very cheap Data Assimilation (DA) method, I show an alternative approach to classical DA for numerical climate models which produce a large amount of "big data". The problematic features of state-of-the-art high resolution Regional…

Applications · Statistics 2016-10-12 Bijan Fallah

We propose a suitable analytical framework to perform numerical analysis of problems arising in compressible fluid models with uncertain data. We discuss both weak and strong stochastic approach, where the former is based on the knowledge…

Analysis of PDEs · Mathematics 2022-08-24 Eduard Feireisl

Using limited observations of the velocity field of the two-dimensional Navier-Stokes equations, we successfully reconstruct the steady body force that drives the flow. The number of observed data points is less than 10\% of the number of…

Fluid Dynamics · Physics 2024-02-26 Aseel Farhat , Adam Larios , Vincent R. Martinez , Jared P. Whitehead

Machine learning offers an intriguing alternative to first-principles analysis for discovering new physics from experimental data. However, to date, purely data-driven methods have only proven successful in uncovering physical laws…

Data assimilation (DA) solves the inverse problem of inferring initial conditions given data and a model. Here we use biophysically motivated Hodgkin-Huxley (HH) models of avian HVCI neurons, experimentally obtained recordings of these…

Neurons and Cognition · Quantitative Biology 2016-08-17 Daniel Breen , Sasha Shirman , Eve Armstrong , Nirag Kadakia , Henry Abarbanel