Article
Engineering, Mechanical
Reza Sadeghi, Nadav Gasner, Seyedvahid Khodaei, Julio Garcia, Zahra Keshavarz-Motamed
Summary: The optimal course of intervention for patients with coexisting coarctation of the aorta (COA) and mixed valvular disease (MVD) is uncertain. This study developed a computational-mechanics framework to investigate the impact of COA and MVD on aortic fluid dynamics. The results suggest that the presence and severity of MVD should be considered in the evaluation of risks in patients with COA.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Mechanics
Zhenyu Ouyang, Jianzhong Lin
Summary: The hydrodynamic behavior of a two-dimensional elongated micro-swimmer in a bulk fluid was studied using numerical methods. The study found that the swimming speed and power expenditure of different types of swimmers varied depending on their structures and the flow conditions.
Article
Physiology
Boyan Mao, Yue Feng, Mengyao Duan, Yihang Dong, Gaoyang Li, Bao Li, Jincheng Liu, Yuting Guo, Minghui Wei, Zhou Zhao, Youjun Liu
Summary: This study constructed a CABG model to analyze the causes of poor instant patency of LIMAs after surgery. The results showed that competitive flow and anastomotic stenosis were the main causes, and they could be distinguished by analyzing the waveform shape and FFT ratio of the graft flow.
FRONTIERS IN PHYSIOLOGY
(2022)
Article
Mechanics
Qiaodan Chen, Jun Duan, Zhongbao Hou, Guoxiang Hou, Leimin Deng
Summary: Superhydrophobic surfaces with a slip effect have been studied for drag reduction, and a method of enhancing drag reduction performance through pattern adjustment is proposed. The results show that patterns consistent with the flow direction can effectively improve drag reduction effect and consistency, while patterns perpendicular to the flow direction are harmful for drag reduction.
Article
Mechanics
Marco A. Ferrari, Alan Lugarini, Admilson T. Franco
Summary: This study investigates the settling behavior of a single spherical particle in a thixo-viscoplastic fluid using numerical methods. The results show that both dynamic yield stress and microstructural breakdown play crucial roles in facilitating the particle settling.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2021)
Article
Mechanics
Geng Guan, Jianzhong Lin
Summary: This study conducted simulations using the lattice Boltzmann method to investigate the motion and interaction of a pair of squirmers in a shear flow. The effects of different squirmers types, self-propulsion strength, and initial spacing were analyzed. Three typical motion patterns were found in the puller-puller configuration, while five motion patterns were observed in the pusher-pusher configuration. Changes in spacing resulted in transitions between different motion patterns.
Article
Multidisciplinary Sciences
Haruki Yoshida, Shunichi Ishida, Taiki Yamamoto, Takayuki Ishikawa, Yuichi Nagata, Kazuhito Takeuchi, Hironori Ueno, Yohsuke Imai
Summary: In this study, computational fluid dynamics was used to investigate the effects of cilia-induced surface velocity on cerebrospinal fluid (CSF) flow. The results showed that ciliary motility disorder could delay CSF exchange in the lateral ventricles.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2022)
Article
Computer Science, Interdisciplinary Applications
Zongze Li, Wenbin Mao
Summary: Computational fluid dynamics (CFD) study of hemodynamics in the aorta can provide a comprehensive analysis of relevant cardiovascular diseases. One trending approach is to couple the three-element Windkessel model with patient-specific CFD simulations to form a multi-scale model that captures more realistic flow fields. However, case-specific parameters (e.g., Rc, Rp, and C) for the Windkessel model must be tuned to reflect patient-specific flow conditions.
COMPUTERS & FLUIDS
(2023)
Article
Mechanics
Kacper Ostalowski, Jifu Tan
Summary: This study performs three-dimensional simulations on blood flow in a complex patient-specific retina vascular network, considering deformable red blood cells, white blood cells, and obstructed vessels. The results show that blockages can significantly alter flow rates in distant vessels. Cells exhibit a fluctuating flow pattern and can accumulate at bifurcations, leading to physical blockages. The addition of white blood cells decreases local flow rates. A reduced order model accurately predicts hematocrit and flow rate distribution, with the Fahr & UAELIG;us-Lindqvist model being the most accurate.
Article
Engineering, Multidisciplinary
Pei Zhang, Siqi Sun, Yilin Chen, S. A. Galindo-Torres, Weicheng Cui
Summary: This study introduces a hybrid 3D model combining LBM and MPM for FSI with large structural deformations and turbulent flows. The model is validated and tested, showing good agreement and potential future applications.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Mechanics
Qing He, Shi Tao, Xiaoping Yang, Weijian Lu, Zongrun He
Summary: The study introduces the ghost-cell immersed boundary method into DUGKS to handle curved boundaries. Three typical test cases are simulated to validate the accuracy and feasibility of the new IDW-GC-DUGKS method for gaseous microflows.
Article
Computer Science, Interdisciplinary Applications
T. Reis
Summary: A multiphase lattice Boltzmann model is developed for numerically solving the one-fluid flow equations for immiscible fluids. The model utilizes two solvers, one for macroscopic pressure and momentum, and another for a scalar field capturing the interface. It can handle flows with large density and viscosity ratios while maintaining distributed but narrow interfaces.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Cardiac & Cardiovascular Systems
Seyedvahid Khodaei, Louis Garber, Mohamed Abdelkhalek, Nima Maftoon, Ali Emadi, Zahra Keshavarz-Motamed
Summary: Despite the benefits of TAVR, many candidates have coronary artery disease. A computational framework was developed to study the impact of TAVR on coronary and cardiac hemodynamics. The results suggest that TAVR may adversely affect coronary hemodynamics and increase left ventricle workload.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2023)
Article
Mathematics, Applied
Asher Zarth, Fabian Klemens, Gudrun Thater, Mathias J. Krause
Summary: A flexible framework for shape optimisation using lattice Boltzmann methods for incompressible Newtonian fluids is proposed. The method utilizes line search methods for optimization problems and obtains design sensitivities through forward propagation automatic differentiation. The approach models fluid flow problems using homogenised lattice Boltzmann methods with varying permeability to propagate derivative information at parametrised boundaries.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2021)
Article
Computer Science, Software Engineering
Chaoyang Lyu, Wei Li, Mathieu Desbrun, Xiaopei Liu
Summary: This paper proposes an efficient and versatile approach for simulating two-way fluid-solid coupling in the kinetic fluid simulation framework, addressing the challenges of reproducing the interaction between fluids and solids. The novel hybrid approach introduced in the paper ensures a robust and plausible treatment of turbulent flows near moving solids, significantly reducing boundary artifacts. Simple GPU optimizations are also presented to achieve a higher computational efficiency than existing methods.
ACM TRANSACTIONS ON GRAPHICS
(2021)
Article
Engineering, Mechanical
Seyedvahid Khodaei, Reza Sadeghi, Philipp Blanke, Jonathon Leipsic, Ali Emadi, Zahra Keshavarz-Motamed
Summary: Aortic stenosis is a cardiovascular disease that often coexists with other complex diseases, requiring accurate hemodynamics quantification for diagnosis. Current diagnostic methods are lacking, necessitating the development of new non-invasive diagnostic methods.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Multidisciplinary Sciences
Seyedvahid Khodaei, Alison Henstock, Reza Sadeghi, Stephanie Sellers, Philipp Blanke, Jonathon Leipsic, Ali Emadi, Zahra Keshavarz-Motamed
Summary: A new non-invasive diagnostic tool has been developed to provide quantitative metrics for global circulatory and cardiac function, as well as local cardiac fluid dynamics for patients undergoing aortic stenosis surgery. This framework utilizes innovative non-invasive Doppler-based algorithm and a 3D fluid-solid interaction, showing high diagnostic accuracy in clinical validation. The framework is vital for improving clinical outcomes, assessing patient risk, and planning treatment.
SCIENTIFIC REPORTS
(2021)
Article
Biotechnology & Applied Microbiology
Melissa Baiocchi, Shirley Barsoum, Seyedvahid Khodaei, Jose M. de la Torre Hernandez, Sydney E. Valentino, Emily C. Dunford, Maureen J. MacDonald, Zahra Keshavarz-Motamed
Summary: Due to high individual differences in anatomy and pathophysiology of patients, planning individualized treatment requires patient-specific diagnosis. A new less invasive intervention is transcatheter aortic valve replacement (TAVR), while a computational mechanics framework C3VI-DE also shows promise.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2021)
Review
Computer Science, Interdisciplinary Applications
Louis Garber, Seyedvahid Khodaei, Zahra Keshavarz-Motamed
Summary: Cardiovascular computational modelling, especially using lumped parameter modelling (LPM), is becoming increasingly important in early diagnosis, personalized treatment, and research of cardiovascular diseases. LPM's advantages of rapid computation time and simplicity make it a potential tool for developing patient specific cardiovascular digital twin frameworks in the future.
ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING
(2022)
Article
Cardiac & Cardiovascular Systems
Reza Sadeghi, Benjamin Tomka, Seyedvahid Khodaei, Julio Garcia, Javier Ganame, Zahra Keshavarz-Motamed
Summary: The study showed that COA and mixed valvular diseases interacted to worsen abnormal blood flow dynamics and increase disease progression. Additionally, the presence of valvular diseases in patients led to increased workload, highlighting the importance of considering both COA severity and mixed valvular diseases in patient evaluation and treatment planning.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2022)
Article
Engineering, Mechanical
Reza Sadeghi, Nadav Gasner, Seyedvahid Khodaei, Julio Garcia, Zahra Keshavarz-Motamed
Summary: The optimal course of intervention for patients with coexisting coarctation of the aorta (COA) and mixed valvular disease (MVD) is uncertain. This study developed a computational-mechanics framework to investigate the impact of COA and MVD on aortic fluid dynamics. The results suggest that the presence and severity of MVD should be considered in the evaluation of risks in patients with COA.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Multidisciplinary Sciences
Seyedvahid Khodaei, Louis Garber, Julia Bauer, Ali Emadi, Zahra Keshavarz-Motamed
Summary: TAVR patients with CAD may be affected by PVL which limits TAVR benefits and coronary perfusion. PVL may increase LV load, decrease coronary flow, and reduce coronary wall shear stress, promoting atherosclerosis development.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Nikrouz Bahadormanesh, Benjamin Tomka, Mohamed Abdelkhalek, Seyedvahid Khodaei, Nima Maftoon, Zahra Keshavarz-Motamed
Summary: In order to assess the impact of transcatheter aortic valve replacement (TAVR) on valve dynamics and cardiac function, a non-invasive computational framework was developed. While TAVR successfully reduced blood pressure, it did not always lead to improvements in valve dynamics and left ventricle hemodynamics.
SCIENTIFIC REPORTS
(2023)
Article
Multidisciplinary Sciences
Louis Garber, Seyedvahid Khodaei, Nima Maftoon, Zahra Keshavarz-Motamed
Summary: In recent years, transcatheter aortic valve replacement (TAVR) has emerged as the leading method for treating aortic stenosis. However, there are still uncertainties about the impact of TAVR on coronary blood flow, and current technologies for non-invasive assessment of coronary blood flow are limited. This study presents a computational model that can simulate coronary blood flow and generate cardiovascular hemodynamic metrics, providing insight into the individual relationships between TAVR and mean and peak coronary flow rates.
SCIENTIFIC REPORTS
(2023)
Correction
Multidisciplinary Sciences
Nikrouz Bahadormanesh, Benjamin Tomka, Mohamed Abdelkhalek, Seyedvahid Khodaei, Nima Maftoon, Zahra Keshavarz-Motamed
SCIENTIFIC REPORTS
(2023)
Article
Cardiac & Cardiovascular Systems
Seyedvahid Khodaei, Louis Garber, Mohamed Abdelkhalek, Nima Maftoon, Ali Emadi, Zahra Keshavarz-Motamed
Summary: Despite the benefits of TAVR, many candidates have coronary artery disease. A computational framework was developed to study the impact of TAVR on coronary and cardiac hemodynamics. The results suggest that TAVR may adversely affect coronary hemodynamics and increase left ventricle workload.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2023)
Article
Cardiac & Cardiovascular Systems
Seyedvahid Khodaei, Mohamed Abdelkhalek, Nima Maftoon, Ali Emadi, Zahra Keshavarz-Motamed
Summary: This study developed a computational framework to evaluate the effects of transcatheter aortic valve replacement (TAVR). The findings suggest that TAVR may lead to blood stagnation in the neo-sinus region and may not provide sufficient relief for the left ventricle load and improvement in coronary flow.
STRUCTURAL HEART-THE JOURNAL OF THE HEART TEAM
(2023)
Article
Computer Science, Artificial Intelligence
Nikrouz Bahadormanesh, Benjamin Tomka, Mason Kadem, Seyedvahid Khodaei, Zahra Keshavarz-Motamed
Summary: It provides an overview of aortic stenosis (AS) and its impact on patients, as well as the lack of effective tools for evaluating valve dynamics in clinical practice. The researchers developed a non-invasive computational framework using ultrasound technology, which can serve as a diagnostic tool to assess valve dynamics in patients with AS. The framework was validated using clinical data and demonstrated its accuracy and reliability in analyzing and interpreting clinical data.
MEDICAL IMAGE ANALYSIS
(2023)
Article
Mechanics
Mehdi Rahmati, Seyedvahid Khodaei
Summary: Research indicated that fluid viscosity and nanoflow effects can influence the velocity profile inside carbon nanotubes, thereby affecting the stability of CNTs. By deriving a dimensionless velocity profile correction factor, the influence of Knudsen number on system stability is considered. Experimental results showed that considering the effect of non-plug flow velocity profile decreases the predicted critical flow velocity, leading to divergence instability at lower flow velocities.
INTERNATIONAL JOURNAL OF FLUID MECHANICS RESEARCH
(2021)