The Meng group has nearly 10 years focused on the image-based CFD research, particularly as applied to cerebral aneurysm flows. For this Challenge, CFD simulations were performed by PhD student Jianping Xiang, using the commercial finite volume solver, STAR-CD .

The main objective of ECoMMFiT is to advance in the knowledge of the structure of flows and their effect on the heat and mass transfer processes in problems with fundamental, clinical, industrial and environmental interest using experimental, computational and analytical tools. For this Challenge, CFD simulations were performed using the commercial finite-volume solver FLUENT 12 (ANSYS).

FEniCS is a finite element library for ‘automated, efficient solution of differential equations’ (www.fenicsproject.org). The focus has been to develop a high-level software interface that allows the user to type in the equations nearly as they are read. Recent development has involved extensions for parallel computing and building an efficient pipeline for patient specific blood flow simulations based on exporting meshes and boundary markers from Vascular Modelling Toolkit (VMTK, www.vmtk.org). The aim is therefore to evaluate the accuracy and efficiency of one of the developed computational fluid mechanics (CFD) solvers. The simulations were performed according to the given instructions and so that information is not repeated here.

The Biofluids Laboratory at the University of Akron has used Fluent [Ansys Inc., Canonsburg, PA] for image-based computational fluid dynamics (CFD) modeling of physiological flows since the lab’s inception in 2008. Recently our group has focused on modeling of pathophysiological problems in cerebrospinal fluid motion and air flow in the trachea, in addition to past work in cardiovascular problems.

Simulations of flow in a cerebral aneurysm are reported as part of the CFD Challenge Problem for the 2012 Summer Bio-engineering Meeting. Our group, a collaboration between the Marsden and Bazilevs labs at UCSD and Open Source Medical Software Corporation, used an in-house finite element solver. In addition, we report particle residence times obtained by solving an advection diffusion equation in a post-processing step.

Research by the Malek Computational Hemodynamics Laboratory has focused on using computational fluid dynamic (CFD) tools to gain an improved insight of the mechanical environment faced by endothelial cells in and around cerebrovascular atherosclerotic and aneurysmal lesions. More recently, we have been interested in studying the effect of endovascular therapies such as aneurysm-occluding coils and intravascular stents on local microhemodynamics.

The Biofluid Mechanics Laboratory is working on hemodyanamics of medical devices and vessels — carotid bifurcations, coronary arteries and cerebral aneurysms — since mid 90s. For this challenge the simulations were performed by the doctorate student Jens Schaller supported by the student coworker Jan Osman using the commercial solver Fluent (Fluent 6.3.26, Ansys Inc., Canonsburg, USA).

An important focus of our cardiovascular fluid mechanics studies is the development and application of computational fluid dynamics (CFD) tools for patient-specific evaluation of internal hemodynamics in vascular anatomies. The validated unsteady internal flow solver utilized in this study has been applied to a multitude of cardiovascular geometries, particularly Fontan surgical anastomoses, pediatric venous flow confluences 1 , idealized developing embryonic chick-heart models 2 , neonatal aortic arch models and several complex geometries involving jet flow behavior 3 . We have also recently started to explore the capability of this solver for evaluating internal flows and wall shear stresses in abdominal aortic aneursyms. For the 2012 SBC Challenge, 3D transient CFD simulations have been performed for a patient-specific internal carotid artery aneurysm case.

Briefly, this Challenge aims to test the sensitivity of steady and pulsatile pressure drops as predicted by different CFD solvers or groups, and ultimately against in vitro pressure measurements. The current study focuses on the Phase I of the Challenge. We simulated steady state and pulsatile pressure drops based on the nominal surface geometry and specific inlet flow rates on a giant cerebral aneurysm with proximal stenosis.

Mr. Kalsi is currently reading 3rd year Aerospace Engineering at Brunei University, London, this CFD challenge was undertaken as a final year dissertation project under the supervision of Dr. Quan Long at the Brunel Institute for Bioengineering (BIB). Simulations were carried out using the finite volume solver package ANSYS Fluent through the educational license available at Brunel University.

The aim of this paper is to present the results of SBC2012 CFD Challenge Phase I problem using a program developed by the Oshima laboratory at the University of Tokyo.

The Rotterdam group mainly focuses on the influence of shear stress on plaque localization and progression in human coronary and carotid arteries. Since we are in an academic hospital, we always have been working in close collaboration with cardiologists and radiologists. Since clinicians do not have the time or the sources that academic engineering groups have, we limited ourselves to perform the simulations on a standard desktop computer (Intel Xeon six core processor, 2.40 GHz CPU and 12 GB RAM) using commercial finite element software (FIDAP 8.7.4 with GAMBIT 2.4.6) within a reasonable time-frame (the weekend). The simulations were carried out by our PhD student Merih Cibis.

The Bressloff group has focused on cardiovascular disease and its treatment for the last ten years. Possessing close ties with Southampton General Hospital, much of the work has sought understanding and/or solutions to clinically relevant problems, including the design of vascular stents. For the CFD Challenge, preliminary verification studies were performed by Masters student Ahsan Hameed using a fast hex-dominant mesher, Harpoon (Sharc Ltd) and V12.1.4 of the ANSYS Fluent solver (ANSYS, Inc.).

The Institute Biomedical Technology and the Department of Flow, Heat and Combustion Mechanics of Ghent University have for more than a decade worked on the development and analysis of algorithms for the simulation of computational fluid dynamics (CFD) and fluid-structure interaction (FSI). These algorithms are applied to blood flow in large arteries, among others. For this Challenge, grid generation and CFD simulations have been performed by postdoctoral fellow Joris Degroote, using an open-source finite volume flow solver, OpenFOAM .

The Modeling and Analysis group in the Division of Engineering at Mayo Clinic, Rochester works in the area of numerical modeling and experimental validation of cerebral aneurysms. In our modeling we use patient-specific geometries from imaging studies provided by Dr. Kallmes. The CFD analysis is performed with commercial packages Mimics (Materialise, Leuven, Belgium), for segmentation and ANSYS (ANSYS Inc. Canonsburg, PA) for meshing, simulation and post-processing. The experiments are conducted using a tomographic Particle Image Velocimetry system from LaVision Inc. The group is led by Dan Dragomir-Daescu, PhD and David F. Kallmes, MD and consists of two postdoctoral fellows and three engineers. For this project, CFD simulations were performed by postdoctoral fellow Simona Hodis, using the finite volume based solver Fluent.

Dr. Shadden’s group focuses on dynamical systems methods to quantify complex flow, with particular focus on the cardiovascular applications in order to better understand hemodynamic phenomena. For this CFD challenge, simulations were performed by Amirhossein Arzani using a customized version of the finite element solver integrated into SimVascular [1].

The BioFlow Group at Imperial College London develops and uses computational and experimental techniques to study fluid dynamics in organisms with the aim of advancing healthcare applications. Within this framework our group applies Computational Fluid Dynamics (CFD) to gain a better understanding of the initiation of atherosclerotic disease. Our in-house spectral element solver has been applied to idealised [1–2] and anatomically realistic [3] geometries, including the rabbit aorta and its branches [4].

The CABER group is based at the University of Limerick and for the past 15 years has primarily focused on cardiovascular hemodynamics research. A key element of the group’s research has always been in the application of CFD to idealized and patient specific geometries. Recently the group has changed commercial CFD software’s and so currently has access to 2 packages, Star-CCM+ 6.02.007 and Ansys Fluent 12.1.4. For this challenge it was therefore decided to compare both software packages and also to examine variability between users. The Fluent simulations were conducted by postgraduate researcher Adrian Lynch and the Star CCM software was utilized independently by postgraduate researchers Jennifer Costello and Leonard Browne.

This work is a collaborative effort between the Biomechanics and Living System Analysis Laboratory (BIOLISYS) in Cyprus and the Biomechanics Laboratory of IACM/FORTH in Greece. Both labs combine interdisciplinary skills from engineering, medicine and biology to provide solutions to clinical problems associated with cardiovascular and other diseases. For this study, numerical flow simulations were performed using: a) open source software VMTK and commercial software ICEM CFD as pre-processors, b) the finite volume based solver Fluent and c) Tecplot 360 (Amtec Inc.) for post-processing.

For many years, there has been a strong intra Ghent University collaboration between the IBiTech-bioMMeda research group, focusing on the application of fluid and structural mechanics for biomedical problems, and the department of Flow, Heat and Combustion Mechanics with a strong background in developing algorithms for numerical fluid mechanics and fluid-structure interaction (FSI) problems. This collaboration joins the strengths of both groups, with ongoing applications in FSI simulations of heart valves, aortic coarctation, aortic aneurysms etc., thereby integrating in vivo (human and (small) animal) hydraulic bench and numerical research.