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Variational 3D-PIV with sparse descriptors

Katrin Lasinger, Christoph Vogel, Thomas Pock, Konrad Schindler
2018 Measurement science and technology  
We propose a new method for iterative particle reconstruction (IPR), in which the locations and intensities of all particles are inferred in one joint energy minimization.  ...  3D Particle Imaging Velocimetry (3D-PIV) aim to recover the flow field in a volume of fluid, which has been seeded with tracer particles and observed from multiple camera viewpoints.  ...  We thank Markus Holzner for discussions and help with the evaluation.  ... 
doi:10.1088/1361-6501/aab5a0 fatcat:n3lnrlgs2feenph4pexiztob6q

PIV-Based 3D Fluid Flow Reconstruction Using Light Field Camera [article]

Zhong Li, Jinwei Ye, Yu Ji, Hao Sheng, Jingyi Yu
2020 arXiv   pre-print
Particle Imaging Velocimetry (PIV) estimates the flow of fluid by analyzing the motion of injected particles.  ...  We further propose a new motion-constrained optical flow estimation scheme by enforcing local motion rigidity and the Navier-Stoke constraint.  ...  Our approach is developed upon the Particle Imaging Velocimetry (PIV) method that estimates flow motion from movement of injected tracer particles.  ... 
arXiv:1904.06841v2 fatcat:g4bcgmj2gncf3ajgazbfjvmlrq

Application of optical flow for river velocimetry

Musaab Khalid, Lionel Penard, Etienne Memin
2017 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS)  
We present a new method for the application of imagebased river velocimetry. Our method is dedicated to high velocity river flows and it is based on an optical flow scheme.  ...  Our method outperformed traditional PIV-based and original optical flow methods.  ...  Our model clearly improved the results over traditional optical flow and PIV-based method that produces dense estimations).  ... 
doi:10.1109/igarss.2017.8128436 dblp:conf/igarss/KhalidPM17 fatcat:5xnez7xbonhmlhimm5e7wvlq4a

An Optical Flow-Based Approach for Minimally Divergent Velocimetry Data Interpolation

Berkay Kanberoglu, Dhritiman Das, Priya Nair, Pavan Turaga, David Frakes
2019 International Journal of Biomedical Imaging  
In this paper, we present an optical-flow based framework for image interpolation that also minimizes resultant divergence in the interpolated data.  ...  Three-dimensional (3D) biomedical image sets are often acquired with in-plane pixel spacings that are far less than the out-of-plane spacings between images.  ...  Optical flow-based methods have been promising in the area of fluid flow estimation in PIV [46] [47] [48] [49] [50] [51] .  ... 
doi:10.1155/2019/9435163 pmid:30863431 pmcid:PMC6378004 fatcat:ryrud4biavhixkcs4ym5yxf7li

3D Fluid Flow Estimation with Integrated Particle Reconstruction [article]

Katrin Lasinger, Christoph Vogel, Thomas Pock, Konrad Schindler
2018 arXiv   pre-print
The method exhibits greatly (~70%) improved results over a recent baseline with two separate steps for 3D reconstruction and motion estimation.  ...  Whereas the dense motion field makes it possible to include physical a-priori constraints and account for the incompressibility and viscosity of the fluid.  ...  Scene flow has undergone an evolution similar to the one for 3D fluid flow. Early methods started with a fixed, precomputed geometry estimate [26, 27] , with a notable exception [28] .  ... 
arXiv:1804.03037v2 fatcat:b54rarbvgncwpittzcnljpooci

Optical flow for image-based river velocity estimation

M. Khalid, L. Pénard, E. Mémin
2019 Flow Measurement and Instrumentation  
The new motion estimation technique outperformed traditional optical flow and PIV-based methods.  ...  It is based on the so-called optical flow, which is a well developed method for rigid motion estimation in image sequences, devised in computer vision community.  ...  Authors also would like to thank Jérôme Le Coz and Alexandre Hauet for their insightful comments on FUDAA-LSPIV software along with the LSPIV project used in section 5.2.  ... 
doi:10.1016/j.flowmeasinst.2018.11.009 fatcat:umo4gq4uhfajvpneehuwazuz2y

An Optical Flow-Based Approach for Minimally-Divergent Velocimetry Data Interpolation [article]

Berkay Kanberoglu and Dhritiman Das and Priya Nair and Pavan Turaga and David Frakes
2018 arXiv   pre-print
In this paper, we present an optical-flow based framework for image interpolation that also minimizes resultant divergence in the interpolated data.  ...  Three-dimensional (3D) biomedical image sets are often acquired with in-plane pixel spacings that are far less than the out-of-plane spacings between images.  ...  Optical flow-based methods have been promising in the area of fluid flow estimation in PIV [46] [47] [48] [49] [50] [51] .  ... 
arXiv:1812.08882v1 fatcat:isq6ldq4nnef5kgfsi2urst4zu

Neural Particle Image Velocimetry [article]

Nikolay Stulov, Michael Chertkov
2021 arXiv   pre-print
Moreover, existing algorithms for PIV either provide sparse estimations of the flow or require large computational time frame preventing from on-line use.  ...  In the past decades, great progress has been made in the field of optical and particle-based measurement techniques for experimental analysis of fluid flows.  ...  To recap, CNN-based methods provide a dense (per-pixel) motion field similar to OF-based methods at the efficiency of CC-based methods (10-100 ms per image pair).  ... 
arXiv:2101.11950v1 fatcat:kx36sxe76fhcjjmuv5lxd6nfwe

From capture to simulation

James Gregson, Ivo Ihrke, Nils Thuerey, Wolfgang Heidrich
2014 ACM Transactions on Graphics  
Abstract We explore the connection between fluid capture, simulation and proximal methods, a class of algorithms commonly used for inverse problems in image processing and computer vision.  ...  Our key finding is that the proximal operator constraining fluid velocities to be divergence-free is directly equivalent to the pressure-projection methods commonly used in incompressible flow solvers.  ...  Fluid simulation has the goal of calculating the motion of a flow based on a set of boundary conditions and a physical model. Such simulations have a long history in research.  ... 
doi:10.1145/2601097.2601147 fatcat:qnw2ppwbg5cyfbsh2gursa5the

SOLITARY WAVE INTERACTION WITH A SUBMERGED PERMEABLE BREAKWATER: EXPERIMENT AND NUMERICAL MODELING

Yun-Ta Wu, Shih-Chun Hsiao, Guan-Shiue Chen
2012 Coastal Engineering Proceedings  
Also, the 2D numerical model is used to estimate the energy reflection, transmission and dissipation using the energy integral method by varying the aspect ratio and the grain size of the permeable obstacle  ...  This model solves 3D incompressible Navier–Stokes equations with Large-eddy-simulation (LES) model.  ...  , solves the 3D incompressible Navier-Stokes equations with the Large-Eddy-Simulation module for multiphase transient fluid flow.  ... 
doi:10.9753/icce.v33.structures.30 fatcat:lajp6lkt35dsfbmt6vql44alpy

Three-dimensional water entry of a solid body: A computational study

Andrea L. Facci, Maurizio Porfiri, Stefano Ubertini
2016 Journal of Fluids and Structures  
Here, we present a new computational study 11 of the 3D water entry of a solid body with multiple curvatures.  ...  The method of finite volume is utilized to 12 discretize incompressible Navier-Stokes equations in both air and water, and the method of volume of fluid is 13 employed to describe the resulting free-surface  ...  The mechanical energy in a generic portion of the fluid domain Ω is 123 E = Ω 1 2 ρ|u| 2 + ρgy dΩ . (4) Methods 138 To reconstruct the 3D velocity field from planar PIV data, we perform two sets of  ... 
doi:10.1016/j.jfluidstructs.2016.07.015 fatcat:qd6tbetouvf4xlyxhs6ezxivju

Coupled Fluid Density and Motion from Single Views [article]

Marie-Lena Eckert, Wolfgang Heidrich, Nils Thuerey
2018 arXiv   pre-print
We present a novel method to reconstruct a fluid's 3D density and motion based on just a single sequence of images.  ...  More specifically, we propose a novel strategy to infer density updates strongly coupled to previous and current estimates of the flow motion.  ...  In these methods, incompressibility is a crucial constraint for flow motions, but it is difficult to enforce in practice.  ... 
arXiv:1806.06613v1 fatcat:ubid6r6uabfcfbswvsibcuyxaa

Error reduction for time-resolved PIV data based on Navier–Stokes equations

Hong-Ping Wang, Qi Gao, Shi-Zhao Wang, Yu-Hang Li, Zhong-Yi Wang, Jin-Jun Wang
2018 Experiments in Fluids  
The new approach is evaluated by two time-resolved PIV experiments: one on the 2D wake flow of a circular cylinder at low Reynolds number and one on tomographic PIV for the 3D wake flow of a hemisphere  ...  A method for optimizing the value of s is provided.  ...  Working principle The working principle of error reduction for TR-PIV data based on N-S equations will be introduced for the case of a two-dimensional incompressible flow for simplicity.  ... 
doi:10.1007/s00348-018-2605-1 fatcat:27sahdp5f5d5xayosqdkmzxfp4

PIV-based pressure measurement

B W van Oudheusden
2013 Measurement science and technology  
The topic of this paper is a review of the approach to extract pressure fields from flow velocity field data, typically obtained with Particle Image Velocmetry (PIV), by combining the experimental data  ...  This has led to a novel diagnostic methodology for determining the instantaneous flow field pressure in a nonintrusive way, which is rapidly finding acceptance in an increasing variety of application areas  ...  A discussion of a selection of applications, where PIV-based pressure determination has been used with success, may serve to illustrate the potentials provided by this new method and the possible impact  ... 
doi:10.1088/0957-0233/24/3/032001 fatcat:cfqho2ovqrbhnkxacxdh7dikm4

Weighted Least-Squares Finite Element Method for Cardiac Blood Flow Simulation with Echocardiographic Data

Fei Wei, John Westerdale, Eileen M. McMahon, Marek Belohlavek, Jeffrey J. Heys
2012 Computational and Mathematical Methods in Medicine  
As both fluid flow measurement techniques and computer simulation methods continue to improve, there is a growing need for numerical simulation approaches that can assimilate experimental data into the  ...  This approach is applied to two different test problems: a flexible flap that is displaced by a jet of fluid and blood flow in the porcine left ventricle.  ...  Based on error estimated by the experimentalists and the PIV software, a boundary functional weight of w PIV = 1.0 was used for most simulations.  ... 
doi:10.1155/2012/371315 pmid:22312412 pmcid:PMC3270545 fatcat:t66gmvs3xvdr7ivqxivd3l4m4q
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