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A Variational Approach for 3D Motion Estimation of Incompressible PIV Flows [chapter]

Luis Alvarez, Carlos Castaño, Miguel García, Karl Krissian, Luis Mazorra, Agustín Salgado, Javier Sánchez
Lecture Notes in Computer Science  
Recent technological advances allow capturing 3D PIV image sequences of moving particles. In this context, we propose a new threedimensional variational (energy-based) technique.  ...  Estimation of motion has many applications in fluid analysis.  ...  We acknowledge the Research Institute Cemagref Rennes (France) for providing to us the PIV sequence and Prof. F. Scarano for his valuable comments  ... 
doi:10.1007/978-3-540-72823-8_72 dblp:conf/scalespace/AlvarezCGKMSS07 fatcat:omlv5yaovfauzhhnc6ebjdebvm

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

Variational 3D-PIV with sparse descriptors

Katrin Lasinger, Christoph Vogel, Thomas Pock, Konrad Schindler
2018 Measurement science and technology  
We propose a variational model, which makes it possible to directly include physical properties, such as incompressibility and viscosity, in the estimation of the motion field.  ...  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

Variational estimation of experimental fluid flows with physics-based spatio-temporal regularization

Paul Ruhnau, Annette Stahl, Christoph Schnörr
2007 Measurement science and technology  
We present a variational approach to motion estimation of instationary experimental fluid flows from image sequences.  ...  variations of flow estimates.  ...  Acknowledgment The authors thank Johan Carlier (Cemagref) for providing the 2D image sequences and Rainer Hain (TU Braunschweig) for providing the cross-correlation estimates.  ... 
doi:10.1088/0957-0233/18/3/027 fatcat:r3u7syx63jewnks3y7olxjd6ta

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.  ...  [22] introduce a joint approach for 3D reconstruction and flow estimation, however, without considering physical properties of the problem.  ... 
arXiv:1804.03037v2 fatcat:b54rarbvgncwpittzcnljpooci

Three-dimensional reconstruction of cardiac flows based on multi-planar velocity fields

Ahmad Falahatpisheh, Gianni Pedrizzetti, Arash Kheradvar
2014 Experiments in Fluids  
In order to overcome these current limitations, we introduce a multi-planar velocity reconstruction approach that can characterize 3D incompressible flows based on the reconstruction of 2D velocity fields  ...  In order to overcome these current limitations, we introduce a multi-planar velocity reconstruction approach that can characterize 3D incompressible flows based on the reconstruction of 2D Electronic supplementary  ...  The authors are also grateful to Professor Federico Domenichini for providing his DNS data.  ... 
doi:10.1007/s00348-014-1848-8 fatcat:mjxhi6cawjdlnk4yj3mgcejmfq

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  
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.  ...  In this paper, we present an optical-flow based framework for image interpolation that also minimizes resultant divergence in the interpolated data.  ...  Optical flow methods estimate the motion between two consecutive image frames that were acquired at times and + . A flow vector for every pixel is calculated.  ... 
doi:10.1155/2019/9435163 pmid:30863431 pmcid:PMC6378004 fatcat:ryrud4biavhixkcs4ym5yxf7li

Fluid Dynamics of Bacterial Turbulence

Jörn Dunkel, Sebastian Heidenreich, Knut Drescher, Henricus H. Wensink, Markus Bär, Raymond E. Goldstein
2013 Physical Review Letters  
We report experiments on active turbulence in highly concentrated 3D suspensions of Bacillus subtilis and compare them with a minimal fourth-order vector-field theory for incompressible bacterial dynamics  ...  Self-sustained turbulent structures have been observed in a wide range of living fluids, yet no quantitative theory exists to explain their properties.  ...  Generally, the VCFs and VACFs respond sensitively to parameter variations in the simulations, suggesting that the estimates in Table I are accurate within 10-15% for quasi-incompressible B. subtilis  ... 
doi:10.1103/physrevlett.110.228102 pmid:23767750 fatcat:mqfoknfmyvbrtavugbjhxnoyv4

Variational fluid flow measurements from image sequences: synopsis and perspectives

Dominique Heitz, Etienne Mémin, Christoph Schnörr
2009 Experiments in Fluids  
Variational approaches to image motion segmentation has been an active field of study in image processing and computer vision for two decades.  ...  We outline promising research directions and point out the potential of variational techniques in combination with correlation-based PIV methods, for improving the consistency of fluid flow estimation  ...  of incompressible flows as a special case.  ... 
doi:10.1007/s00348-009-0778-3 fatcat:p2voujunsrdwxasipwp6ve5syq

A variational approach for particle tracking velocimetry

P Ruhnau, C Guetter, T Putze, C Schnörr
2005 Measurement science and technology  
We introduce a novel variational approach for evaluating PTV image pairs and sequences in two and three dimensions.  ...  The experimental evaluation shows that our variational method competes with three alternative approaches. We outline the potential of our method for further developments.  ...  To this end, we have to replace the continuous data term of variational approaches to PIV with a discrete non-differentiable particle matching term for PTV.  ... 
doi:10.1088/0957-0233/16/7/007 fatcat:d64ehqzhevfmro4v43o5vybapq

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.  ...  We present a novel motion estimation technique for image-based river velocimetry.  ...  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

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  ...  Some consequences of applying planar PIV in a 3D flow Even when the planar pressure field is to be determined from the momentum equation, the contribution of out-of-plane motion needs to be accounted for  ... 
doi:10.1088/0957-0233/24/3/032001 fatcat:cfqho2ovqrbhnkxacxdh7dikm4

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.  ...  Our approach is expected to aid in 18 the validation of new semi-analytical solutions and to offer a viable means for conducting parametric studies 19 and design optimization on marine vessels. 20 spatial  ...  , with 165 an estimation of the axial flow.  ... 
doi:10.1016/j.jfluidstructs.2016.07.015 fatcat:qd6tbetouvf4xlyxhs6ezxivju

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
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.  ...  In this paper, we present an optical-flow based framework for image interpolation that also minimizes resultant divergence in the interpolated data.  ...  Optical flow methods estimate the motion between two consecutive image frames that were acquired at times t and t + δt . A flow vector for every pixel is calculated.  ... 
arXiv:1812.08882v1 fatcat:isq6ldq4nnef5kgfsi2urst4zu

An evaluation of optical flow algorithms for background oriented schlieren imaging

Bradley Atcheson, Wolfgang Heidrich, Ivo Ihrke
2008 Experiments in Fluids  
The background oriented schlieren method (BOS) allows for accurate flow measurements with a simple experimental configuration.  ...  Experiments with both synthetic and real datasets show that the performance of BOS systems can be significantly improved through a combination of optical flow algorithms and multiscale background.  ...  Although a vast number of variations have been proposed on both approaches over the years, a number of representative methods can be chosen for each category.  ... 
doi:10.1007/s00348-008-0572-7 fatcat:gkddkeswlvgfjkcwz5tuiws3bq
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