Modelling platelet–blood flow interaction using the subcellular element Langevin method

In this paper, a new three-dimensional modelling approach is described for studying fluid–viscoelastic cell interaction, the subcellular element Langevin (SCEL) method, with cells modelled by subcellular elements (SCEs) and SCE cells coupled with fluid flow and substrate models by using the Langevin equation. It is demonstrated that: (i) the new method is computationally efficient, scaling as 𝒪( N ) for N SCEs; (ii) cell geometry, stiffness and adhesivity can be modelled by directly relating parameters to experimentally measured values; (iii) modelling the fluid–platelet interface as a surface leads to a very good correlation with experimentally observed platelet flow interactions. Using this method, the three-dimensional motion of a viscoelastic platelet in a shear blood flow was simulated and compared with experiments on tracking platelets in a blood chamber. It is shown that the complex platelet-flipping dynamics under linear shear flows can be accurately recovered with the SCEL model when compared with the experiments. All experimental details and electronic supplementary material are archived at http://biomath.math.nd.edu/scelsupplementaryinformation/.

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High-speed volumetric two-photon fluorescence imaging of neurovascular dynamics

Nature Communications ◽

10.1038/s41467-020-19851-1 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Jiang Lan Fan ◽

Jose A. Rivera ◽

Wei Sun ◽

John Peterson ◽

Henry Haeberle ◽

...

Keyword(s):

Blood Flow ◽

High Speed ◽

Laser Scanning ◽

Three Dimensional ◽

Laser Scanning Microscopy ◽

Fluorescence Signal ◽

Imaging Method ◽

Spatiotemporal Resolution ◽

Two Photon

AbstractUnderstanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.

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Modeling of aortic valve stenosis using fluid-structure interaction method

Perfusion ◽

10.1177/0267659121998549 ◽

2021 ◽

pp. 026765912199854

Author(s):

Mohammad Javad Ghasemi Pour ◽

Kamran Hassani ◽

Morteza Khayat ◽

Shahram Etemadi Haghighi

Keyword(s):

Blood Flow ◽

Aortic Valve ◽

Fluid Structure Interaction ◽

Three Dimensional ◽

Fluid Structure ◽

Structure Interaction ◽

Relaxation Phase ◽

Exercise Condition ◽

Time Dependent Domain ◽

Comparison Of The Results

Background and objectives: Fluid structure interaction (FSI) is defined as interaction of the structures with contacting fluids. The aortic valve experiences the interaction with blood flow in systolic phase. In this study, we have tried to predict the hemodynamics of blood flow through a normal and stenotic aortic valve in two relaxation and exercise conditions using a three-dimensional FSI method. Methods: The aorta valve was modeled as a three-dimensional geometry including a normal model and two others with 25% and 50% stenosis. The geometry of the aortic valve was extracted from CT images and the models were generated by MMIMCS software and then they were implemented in ANSYS software. The pulsatile flow rate was used for all cases and the numerical simulations were conducted based on a time-dependent domain. Results: The obtained results including the velocity, pressure, and shear stress contours in different systolic time sequences were explained and discussed. The maximum blood flow velocity in relaxation phase was obtained 1.62 m/s (normal valve), 3.78 m/s (25% stenosed valve), and 4.73 m/s (50% stenosed valve). In exercise condition, the maximum velocities are 2.86, 4.32, and 5.42 m/s respectively. The maximum blood pressure in relaxation phase was calculated 111.45 mmHg (normal), 148.66 mmHg (25% stenosed), and 164.21 mmHg (50% stenosed). However, the calculated values in exercise situation were 129.57, 163.58, and 191.26 mmHg. The validation of the predicted results was also conducted using existing literature. Conclusions: We believe that such model are useful tools for biomechanical experts. The further studies should be done using experimental data and the data are implemented on the boundary conditions for better comparison of the results.

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Advances in coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410020966454 ◽

2020 ◽

pp. 095441002096645

Author(s):

Jie Gao ◽

Chunde Tao ◽

Dongchen Huo ◽

Guojie Wang

Keyword(s):

Performance Improvement ◽

High Efficiency ◽

Three Dimensional ◽

Great Influence ◽

Aerodynamic Characteristics ◽

Turbine Engines ◽

Gas Turbine Engines ◽

Axial Turbine ◽

Flow Interactions ◽

And Performance

Marine, industrial, turboprop and turboshaft gas turbine engines use nonaxisymmetric exhaust volutes for flow diffusion and pressure recovery. These processes result in a three-dimensional complex turbulent flow in the exhaust volute. The flows in the axial turbine and nonaxisymmetric exhaust volute are closely coupled and inherently unsteady, and they have a great influence on the turbine and exhaust aerodynamic characteristics. Therefore, it is very necessary to carry out research on coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics, so as to provide reference for the high-efficiency turbine-volute designs. This paper summarizes and analyzes the recent advances in the field of coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery. This review covers the following topics that are important for turbine and volute coupled designs: (1) flow and loss characteristics of nonaxisymmetric exhaust volutes, (2) flow interactions between axial turbine and nonaxisymmetric exhaust volute, (3) improvement of turbine and volute performance within spatial limitations and (4) research methods of coupled turbine and exhaust volute aerodynamics. The emphasis is placed on the turbine-volute interactions and performance improvement. We also present our own insights regarding the current research trends and the prospects for future developments.

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Mass transfer and blood flow in a patient-specific three-dimensional Willis circle

International Communications in Heat and Mass Transfer ◽

10.1016/j.icheatmasstransfer.2021.105369 ◽

2021 ◽

Vol 126 ◽

pp. 105369

Author(s):

Alessio Pignani ◽

Ivan Di Venuta ◽

Andrea Boghi ◽

Fabio Gori

Keyword(s):

Mass Transfer ◽

Blood Flow ◽

Three Dimensional ◽

Patient Specific

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Macro-Modelling of Laser Micro-Joints for Understanding Joint Strength in Electric Vehicle Battery Interconnects

Materials ◽

10.3390/ma14133552 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3552

Author(s):

Abhishek Das ◽

Richard Beaumont ◽

Iain Masters ◽

Paul Haney

Keyword(s):

Joint Strength ◽

Structural Model ◽

Design Stage ◽

Structural Modelling ◽

Laser Weld ◽

Computationally Efficient ◽

Early Design Stage ◽

Lap Shear ◽

Battery Module ◽

Modelling Approach

Laser micro-welding is increasingly being used to produce electrically conductive joints within a battery module of an automotive battery pack. To understand the joint strength of these laser welds at an early design stage, micro-joints are required to be modelled. Additionally, structural modelling of the battery module along with the electrical interconnects is important for understanding the crash safety of electric vehicles. Fusion zone based micro-modelling of laser welding is not a suitable approach for structural modelling due to the computational inefficiency and the difficulty of integrating with the module model. Instead, a macro-model which computationally efficient and easy to integrate with the structural model can be useful to replicate the behaviour of the laser weld. A macro-modelling approach was adopted in this paper to model the mechanical behaviour of laser micro-weld. The simulations were based on 5 mm diameter circular laser weld and developed from the experimental data for both the lap shear and T-peel tests. This modelling approach was extended to obtain the joint strengths for 3 mm diameter circular seams, 5 mm and 10 mm linear seams. The predicted load–displacement curves showed a close agreement with the test data.

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Non-contact scanning diffuse correlation tomography system for three-dimensional blood flow imaging in a murine bone graft model

Biomedical Optics Express ◽

10.1364/boe.6.002695 ◽

2015 ◽

Vol 6 (7) ◽

pp. 2695 ◽

Cited By ~ 14

Author(s):

Songfeng Han ◽

Johannes Johansson ◽

Miguel Mireles ◽

Ashley R. Proctor ◽

Michael D. Hoffman ◽

...

Keyword(s):

Blood Flow ◽

Bone Graft ◽

Three Dimensional ◽

Flow Imaging ◽

Blood Flow Imaging ◽

Tomography System

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The influence of changing blood flow during the heart cycle of three-dimensional contrast enhanced power doppler imaging

European Urology Supplements ◽

10.1016/s1569-9056(03)80306-8 ◽

2003 ◽

Vol 2 (1) ◽

pp. 77

Author(s):

H. Van Moerkerk ◽

H. Wijkstra ◽

F.M.J. Debruyne ◽

J.J.M.C. De la Rosette

Keyword(s):

Blood Flow ◽

Power Doppler ◽

Three Dimensional ◽

Doppler Imaging ◽

Contrast Enhanced ◽

Power Doppler Imaging ◽

Heart Cycle

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Assessment of the Evolution Equation Modelling approach for three-dimensional expanding wrinkled premixed flames

Combustion and Flame ◽

10.1016/j.combustflame.2011.12.019 ◽

2012 ◽

Vol 159 (5) ◽

pp. 1932-1948 ◽

Cited By ~ 7

Author(s):

Eric Albin ◽

Yves D’Angelo

Keyword(s):

Evolution Equation ◽

Premixed Flames ◽

Three Dimensional ◽

Equation Modelling ◽

Modelling Approach

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Direct simulation of evolution and control of three-dimensional instabilities in attachment-line boundary layers

Journal of Fluid Mechanics ◽

10.1017/s0022112095002746 ◽

1995 ◽

Vol 291 ◽

pp. 369-392 ◽

Cited By ~ 32

Author(s):

Ronald D. Joslin

Keyword(s):

Boundary Layer ◽

Stokes Equations ◽

Three Dimensional ◽

Plate Boundary ◽

Navier Stokes ◽

Two Dimensional ◽

Computationally Efficient ◽

Simulation Results ◽

Dimensional Simulation ◽

Attachment Line

The spatial evolution of three-dimensional disturbances in an attachment-line boundary layer is computed by direct numerical simulation of the unsteady, incompressible Navier–Stokes equations. Disturbances are introduced into the boundary layer by harmonic sources that involve unsteady suction and blowing through the wall. Various harmonic-source generators are implemented on or near the attachment line, and the disturbance evolutions are compared. Previous two-dimensional simulation results and nonparallel theory are compared with the present results. The three-dimensional simulation results for disturbances with quasi-two-dimensional features indicate growth rates of only a few percent larger than pure two-dimensional results; however, the results are close enough to enable the use of the more computationally efficient, two-dimensional approach. However, true three-dimensional disturbances are more likely in practice and are more stable than two-dimensional disturbances. Disturbances generated off (but near) the attachment line spread both away from and toward the attachment line as they evolve. The evolution pattern is comparable to wave packets in flat-plate boundary-layer flows. Suction stabilizes the quasi-two-dimensional attachment-line instabilities, and blowing destabilizes these instabilities; these results qualitatively agree with the theory. Furthermore, suction stabilizes the disturbances that develop off the attachment line. Clearly, disturbances that are generated near the attachment line can supply energy to attachment-line instabilities, but suction can be used to stabilize these instabilities.

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