Computation of residence time in the simulation of pulsatile ventricular assist devices

Long, Christopher C.; Esmaily, Mahdi; Marsden, Alison L.; Bazilevs, Yuri

doi:10.1007/s00466-013-0931-y

Cited by 98 publications

(49 citation statements)

References 59 publications

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“…Furthermore, the flow patterns observed for aortic regurgitation are considerably complex, lacking the simple coherent pattern offered by the mitral vortex in the healthy flow scenario, and therefore will characteristically delay blood from being ejected overall. This same question of the importance of the healthy left ventricular flow pattern on particle residence time may also have significant implications in the design of left ventricular assist devices, the flow patterns of which considerably deviate from those of a natural heart (Long et al, 2014).…”

Section: B Blood Transport Characteristics Associated With Aortic Rementioning

confidence: 99%

Material transport in the left ventricle with aortic valve regurgitation

2018

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This experimental in vitro work investigates material transport properties in a model left ventricle in the case of aortic regurgitation, a valvular disease characterized by a leaking aortic valve and consequently double-jet filling within the elastic left ventricular geometry. This study suggests that material transport phenomena are strongly determined by the motion of the counterrotating vortices driven by the regurgitant aortic and mitral jets. The overall particle residence time appears to be significantly longer with moderate aortic regurgitation, attributed to the dynamics resulting from the timing between the onset of the two jets. Increasing regurgitation severity is shown to be associated with higher frequencies in the time-frequency spectra of the velocity signals at various points in the flow, suggesting nonlaminar mixing past moderate regurgitation. Additionally, a large part of the regurgitant inflow is retained for at least one cardiac cycle. Such an increase in particle residence time accompanied by the occurrence and persistence of a number of attracting Lagrangian coherent structures presents favorable conditions and locations for activated platelets to agglomerate within the left ventricle, potentially posing an additional risk factor for patients with aortic regurgitation.

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Section: B Blood Transport Characteristics Associated With Aortic Rementioning

confidence: 99%

Material transport in the left ventricle with aortic valve regurgitation

2018

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“…38 The ALE-SUPS, RBVMS and ALE-VMS have been applied to many classes of FSI, MBI and fluid mechanics problems. The classes of problems include ram-air parachute FSI, 32 wind-turbine aerodynamics and FSI, [39][40][41][42][43][44][45][46][47][48][49] more specifically, vertical-axis wind turbines, 50,51,48,49 floating wind turbines, 52 wind turbines in atmospheric boundary layers, 53,[47][48][49] and fatigue damage in wind-turbine blades, 54 patient-specific cardiovascular fluid mechanics and FSI, 55,25,[56][57][58][59][60] biomedical-device FSI, [61][62][63][64][65][66] ship hydrodynamics with free-surface flow and fluid-object interaction, 67,68 hydrodynamics and FSI of a hydraulic arresting gear, 69,70 hydrodynamics of tidal-stream turbines with freesurface flow, 71 passive-morphing FSI in turbomachinery, 72 bioinspired FSI for marine propulsion, 73,74 bridge aerodynamics and fluid-object interaction, [75]…”

Section: Stabilized and Vms Space-time Computational Methodsmentioning

confidence: 99%

A node-numbering-invariant directional length scale for simplex elements

Takizawa

Ueda

Tezduyar

2019

Math. Models Methods Appl. Sci.

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Variational multiscale methods, and their precursors, stabilized methods, have been very popular in flow computations in the past several decades. Stabilization parameters embedded in most of these methods play a significant role. The parameters almost always involve element length scales, most of the time in specific directions, such as the direction of the flow or solution gradient. We require the length scales, including the directional length scales, to have node-numbering invariance for all element types, including simplex elements. We propose a length scale expression meeting that requirement. We analytically evaluate the expression in the context of simplex elements and compared to one of the most widely used length scale expressions and show the levels of noninvariance avoided.

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“…31 They have been applied to many classes of FSI, MBI and fluid mechanics problems. The classes of problems include wind-turbine aerodynamics and FSI, [32][33][34][35][36][37][38][39][40][41][42] more specifically, vertical-axis wind turbines, [41][42][43][44] floating wind turbines, 45 wind turbines in atmospheric boundary layers, [40][41][42]46 and fatigue damage in wind-turbine blades, 47 patient-specific cardiovascular fluid mechanics and FSI, 19,[48][49][50][51][52][53] biomedical-device FSI, [54][55][56][57][58][59] ship hydrodynamics with free-surface flow and fluid-object interaction, 60,61 hydrodynamics and FSI of a hydraulic arresting gear, 62,63 hydrodynamics of tidal-stream turbines with free-surface flow, 64 bioinspired FSI for marine propulsion, 65,66 bridge aerodynamics and fluid-object interaction, [67][68][69] and mixed ALE-VMS/Immersogeometric computations…”

Section: St-vmsmentioning

confidence: 99%

Space–time Isogeometric flow analysis with built-in Reynolds-equation limit

Kuraishi

Takizawa

Tezduyar

2019

Math. Models Methods Appl. Sci.

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We present a space–time (ST) computational flow analysis method with built-in Reynolds-equation limit. The method enables solution of lubrication fluid dynamics problems with a computational cost comparable to that of the Reynolds-equation model for the comparable solution quality, but with the computational flexibility to go beyond the limitations of the Reynolds-equation model. The key components of the method are the ST Variational Multiscale (ST-VMS) method, ST Isogeometric Analysis (ST-IGA), and the ST Slip Interface (ST-SI) method. The VMS feature of the ST-VMS serves as a numerical stabilization method with a good track record, the moving-mesh feature of the ST framework enables high-resolution flow computation near the moving fluid–solid interfaces, and the higher-order accuracy of the ST framework strengthens both features. The ST-IGA enables more accurate representation of the solid-surface geometries and increased accuracy in the flow solution in general. With the ST-IGA, even with just one quadratic NURBS element across the gap of the lubrication fluid dynamics problem, we reach a solution quality comparable to that of the Reynolds-equation model. The ST-SI enables moving-mesh computation when the spinning solid surface is noncircular. The mesh covering the solid surface spins with it, retaining the high-resolution representation of the flow near the surface, and the SI between the spinning mesh and the rest of the mesh accurately connects the two sides of the solution. We present detailed 2D test computations to show how the method performs compared to the Reynolds-equation model, compared to finite element discretization, at different circumferential and normal mesh refinement levels, when there is an SI in the mesh, and when the no-slip boundary conditions are weakly-enforced.

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Computation of residence time in the simulation of pulsatile ventricular assist devices

Cited by 98 publications

References 59 publications

Material transport in the left ventricle with aortic valve regurgitation

Material transport in the left ventricle with aortic valve regurgitation

A node-numbering-invariant directional length scale for simplex elements

Space–time Isogeometric flow analysis with built-in Reynolds-equation limit

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