Article
Chemistry, Analytical
Jianyu Ji, Shizhi Qian, Zhaohui Liu
Summary: This study numerically investigates the electroosmotic flow (EOF) of viscoelastic fluid and finds that under certain conditions, the EOF of viscoelastic fluid becomes unstable and vortices form at the upstream of the constriction. Compared to Newtonian fluid, the EOF velocity of viscoelastic fluid is spatially and temporally dependent, with the velocity at the exit much higher than the entrance.
Article
Computer Science, Interdisciplinary Applications
Tsorng-Whay Pan, Shang-Huan Chiu
Summary: In this article, a numerical method for simulating sedimentation of balls in a three-dimensional channel filled with an Oldroyd-B fluid is presented. The method combines a distributed Lagrange multiplier/fictitious domain method with a factorization approach. The validity of the method is confirmed by comparing the obtained results with those reported in literature. Additionally, the influence of fluid elasticity on the formation of ball chain in Oldroyd-B fluids is studied, showing the capability of the method.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Chemistry, Physical
Zhihao Zhang, Lei Tang, Yu Hao, Li Peng, Jie Li
Summary: The research investigates the electroosmotic flow of viscoelastic fluids in nanochannels and its effects on ion transport and vortex formation. The results show that viscoelasticity suppresses vortices in the ion depletion zone and influences their symmetries and time-dependent properties. The improvement in analyte preconcentration efficiency and the implications for nanochannel biosensing technology highlight the significance of this study.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Article
Mechanics
Xiaoyang Xu, Yao-Lin Jiang
Summary: This study presents a smoothed particle hydrodynamics (SPH) method for simulating transient non-isothermal viscoelastic flows with free surfaces. The proposed SPH method is capable of accurately and stably simulating flow behavior in an entirely meshfree framework.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2022)
Article
Mechanics
Rajat Dandekar, Arezoo M. Ardekani
Summary: This study theoretically investigates the forces and moments acting on two nearly touching spheres immersed in a second-order fluid, dividing the problem into four sub-classes to analyze the effects of viscoelasticity. It is found that the introduction of viscoelasticity affects the force experienced by the spheres, with non-zero contributions along the line joining the sphere centers and generating lift forces for asymmetric sub-classes. The analytical expressions obtained in this study can be used in computational schemes to study the behavior of particles in a viscoelastic fluid.
Article
Physics, Multidisciplinary
Atul Kumar Shukla, Mukesh Kumar Awasthi, Shivam Agarwal
Summary: The present study investigated the stability of a spherical interface formed by a combination of a viscous fluid and an Oldroyd B viscoelastic fluid using linear stability analysis. The study found that the stability of the interface increases with an increase in the viscoelasticity of the fluid.
CHINESE JOURNAL OF PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
C. Fernandes, S. A. Faroughi, R. Ribeiro, A. Isabel, G. H. McKinley
Summary: Accurately resolving the coupled momentum transfer between the liquid and solid phases of complex fluids is essential in multiphase transport processes. This study uses direct numerical simulations and closure drag laws to investigate the flow characteristics of viscoelastic fluids through static random arrays of spherical particles.
ENGINEERING WITH COMPUTERS
(2022)
Article
Mathematics
Gerasim Vladimirovich Krivovichev
Summary: The paper compares different one-dimensional models of blood flow, taking into account the non-Newtonian property of blood. It analytically solves the simplified nonlinear problem for a semi-infinite vessel with constant properties and compares the solutions for different models. The effects of velocity profile flattening and hematocrit value on deviation from the Newtonian model are investigated.
Article
Computer Science, Interdisciplinary Applications
A. Lucca, S. Busto, L. O. Mueller, E. F. Toro, M. Dumbser
Summary: A novel staggered semi-implicit finite volume method is proposed for simulating one-dimensional blood flow in networks of elastic and viscoelastic vessels. The method efficiently handles the various subsystems and introduces a simple three-dimensional approach for treating junctions. Validation tests show good agreement with available analytical, experimental, and numerical data.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Mechanics
B. Taghilou, M. Pourjafar-Chelikdani, S. M. Taghavi, A. Mahdavi Nejad, A. Kuchumov, K. Sadeghy
Summary: This study investigates the effect of liquid elasticity on the peristaltic transport of a single drop. The results show that the elasticity of a drop has a negligible effect on its transport velocity when placed on the centerline, but significantly delays its migration to the centerline if the drop is off-center. Moreover, when only the liquid surrounding the drop is viscoelastic, elastic stresses have a significant but non-monotonic effect on the drop velocity.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2022)
Article
Thermodynamics
Mukesh Kumar Awasthi
Summary: This paper examines the linear stability of the interface formed by a viscoelastic liquid and a viscous gas, considering the significant influence of heat and mass transfer at the interface. The effects of various physical parameters on the stability of the liquid/gas interface are investigated through theoretical and graphical analysis in the study.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Computer Science, Interdisciplinary Applications
Yudong Li, Yan Li, Zhiqiang Feng
Summary: The decoupled finite particle coupled with smoothed particle hydrodynamics (DFP-SPH) method is developed for simulating viscoelastic fluid flow with a free surface. A particle shifting technology is introduced to eliminate the tensile instability and nonuniformity of fluid particles. The accuracy, consistency, and convergence of the method are investigated on various benchmarks, and the validity of the particle shifting technology is verified through numerical simulations.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Physics, Multidisciplinary
Mohammad Khalid, V Shankar, Ganesh Subramanian
Summary: Research has shown that highly concentrated polymer solutions exhibit linear instability in the absence of inertia under high elasticity conditions, which persists up to a Reynolds number of O(1000). This may provide insights into the transition to turbulence in elastic solids.
PHYSICAL REVIEW LETTERS
(2021)
Article
Mechanics
B. Taghilou, S. M. J. Sobhani, M. Pourjafar-Chelikdani, A. Mahdavi Nejad, M. R. Ghoroghi, K. Sadeghy
Summary: Numerical investigation on transporting viscoelastic fluids using a simple mechanism of a rotating cylinder asymmetrically placed across a duct showed that fluid's elasticity negatively affects the performance of viscous micro-pumps. The drop in efficiency is predicted to increase with higher Deborah numbers, reaching around 30% at De = 1 compared to Newtonian fluids of the same viscosity.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2021)
Article
Engineering, Multidisciplinary
Jaekwang Kim
Summary: This work presents an adjoint-based sensitivity analysis of viscoelastic fluid flow around a cylinder in a confined channel. The study formulates a set of continuous adjoint governing equations to quantify the local sensitivities of rheological model parameters on the drag of the cylinder. The outcome includes resistance-sensitivity maps for the Oldroyd-B model parameters, indicating the local relative importance of different physical mechanisms.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Engineering, Multidisciplinary
Tomas Bodnar, Philippe Fraunie
APPLIED MATHEMATICAL MODELLING
(2020)
Article
Mathematics
Marilia Pires, Tomas Bodnar
Summary: This paper presents a numerical evaluation of two different artificial stress diffusion techniques for the stabilization of viscoelastic fluid flows at high Weissenberg numbers. The numerical simulations have shown that the proposed temporal stress diffusion method efficiently stabilizes the simulations and vanishes when the solution reaches a steady state, without affecting the final solution.
Article
Multidisciplinary Sciences
Matteo Caggio, Mario Schiavon, Francesco Tampieri, Tomas Bodnar
Summary: This paper presents a new modification to the second order turbulence closure that removes the limitation posed by the critical gradient Richardson number in Mellor-Yamada style models. The newly modified model's mean wind speed and potential temperature profiles are derived in terms of similarity and structure functions, depending on the gradient Richardson number. The derivation is based on a second order boundary layer approximation under neutral to very stable stratification conditions. The paper also investigates the variances and covariances of the turbulent fluctuations with respect to the gradient Richardson number, and compares the predictions of the new model with well known existing models.
SN APPLIED SCIENCES
(2022)
Article
Multidisciplinary Sciences
Marilia Pires, Tomas Bodnar
Summary: This article presents two different artificial diffusion stabilization methods for numerical simulations of steady Oldroyd-B fluid flows. These methods are based on the idea of vanishing in time added stabilization terms, which are gradually eliminated during the time-marching process towards the steady state solution. These additional terms naturally disappear and do not affect the final result. The numerical simulations are performed on a simple steady 2D case of Oldroyd-B fluid flow in a symmetrical corrugated channel. The numerical solver uses finite element discretization in space and the characteristic Galerkin method for pseudo-time discretization. Numerical results are presented in the form of isolines and graphs of selected flow variables to assess the potential efficiency of the different stabilization techniques used.
SN APPLIED SCIENCES
(2023)
Article
Physics, Fluids & Plasmas
Tomas Bodnar, Adelia Sequeira
Summary: This paper presents a numerical comparison of viscoelastic shear-thinning fluid flow using a generalized Oldroyd-B model and Johnson-Segalman model. The differences and characteristics between the two models are pointed out, and blood flow simulations are performed to demonstrate the qualitative differences in different flow conditions.
Proceedings Paper
Engineering, Mechanical
Anna Lancmanova, Tomas Bodnar
Summary: This contribution introduces the initial results of a newly developed numerical solver for studying flow properties and behavior in branching channels. The 2D incompressible fluid flow is simulated using Navier Stokes equations and a finite-difference scheme. Tests were conducted on selected geometries to evaluate the model's overall behavior and response to different conditions.
TOPICAL PROBLEMS OF FLUID MECHANICS 2021
(2021)
Proceedings Paper
Engineering, Mechanical
Marilia Pires, Tomas Bodnar
Summary: This work presents numerical tests on the finite element solution of incompressible Oldroyd-B fluid flows using different types of numerical stabilization. The goal is to make the diffusion coefficient vanish in time, ensuring that the final solution remains unaffected by the added diffusion term.
TOPICAL PROBLEMS OF FLUID MECHANICS 2021
(2021)
Proceedings Paper
Engineering, Mechanical
Matteo Caggio, Mario Schiavon, Francesco Tampieri, Tomas Bodnar
Summary: The purpose of this communication is to present a derivation of the non-dimensional vertical gradients of the mean wind speed and mean potential temperature for very stable atmospheric conditions. The analysis is based on second-order model equations in boundary layer approximations with proposed new heat flux equations. The model uses a recent closure for the pressure-temperature correlation, avoiding issues related to the critical threshold for the Richardson number.
TOPICAL PROBLEMS OF FLUID MECHANICS 2021
(2021)
Article
Engineering, Multidisciplinary
Tomas Bodnar, Philippe Fraunie, Karel Kozel
Summary: This paper presents the general modified equation for a family of finite-difference schemes solving one-dimensional advection equation, considering both explicit and implicit schemes working at two time levels and having three point spatial support. By discussing classical schemes as examples, the paper shows the possible implications of the modified equation on the properties of the numerical methods being considered.
Article
Mathematics, Applied
Tomas Bodnar, Philippe Fraunie, Petr Knobloch, Hynek Reznicek
Summary: The efficiency of newly proposed far-field boundary simulations of wall-bounded, stably stratified flows was numerically studied in this paper. The comparison of numerical solutions on large and truncated computational domain showed how the solution is affected by the adopted far-field conditions. The study discussed the influence of the newly proposed far-field boundary condition by comparing full domain reference solution and the truncated domain solution.
DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS-SERIES S
(2021)
Article
Engineering, Biomedical
Ana Joao, Alberto Gambaruto, Ricardo Pereira, Adelia Sequeira
COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING-IMAGING AND VISUALIZATION
(2020)
Article
Engineering, Biomedical
Ana Joao, Alberto Gambaruto, Adelia Sequeira
COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING-IMAGING AND VISUALIZATION
(2020)
Article
Mathematics
Adelia Sequeira, Tomas Bodnar
VIETNAM JOURNAL OF MATHEMATICS
(2019)
Article
Physics, Fluids & Plasmas
Vahid Goodarzi Ardakani, Xin Tu, Alberto M. Gambaruto, Iolanda Velho, Jorge Tiago, Adelia Sequeira, Ricardo Pereira
Article
Mathematics, Applied
Peter Frolkovic, Nikola Gajdosova
Summary: This paper presents compact semi-implicit finite difference schemes for solving advection problems using level set methods. Through numerical tests and stability analysis, the accuracy and stability of the proposed schemes are verified.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Md. Rajib Arefin, Jun Tanimoto
Summary: Human behaviors are strongly influenced by social norms, and this study shows that injunctive social norms can lead to bi-stability in evolutionary games. Different games exhibit different outcomes, with some showing the possibility of coexistence or a stable equilibrium.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Dingyi Du, Chunhong Fu, Qingxiang Xu
Summary: A correction and improvement are made on a recent joint work by the second and third authors. An optimal perturbation bound is also clarified for certain 2 x 2 Hermitian matrices.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Pingrui Zhang, Xiaoyun Jiang, Junqing Jia
Summary: In this study, improved uniform error bounds are developed for the long-time dynamics of the nonlinear space fractional Dirac equation in two dimensions. The equation is discretized in time using the Strang splitting method and in space using the Fourier pseudospectral method. The major local truncation error of the numerical methods is established, and improved uniform error estimates are rigorously demonstrated for the semi-discrete scheme and full-discretization. Numerical investigations are presented to verify the error bounds and illustrate the long-time dynamical behaviors of the equation with honeycomb lattice potentials.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Kuan Zou, Wenchen Han, Lan Zhang, Changwei Huang
Summary: This research extends the spatial PGG on hypergraphs and allows cooperators to allocate investments unevenly. The results show that allocating more resources to profitable groups can effectively promote cooperation. Additionally, a moderate negative value of investment preference leads to the lowest level of cooperation.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Kui Du
Summary: This article introduces two new regularized randomized iterative algorithms for finding solutions with certain structures of a linear system ABx = b. Compared to other randomized iterative algorithms, these new algorithms can find sparse solutions and have better performance.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Shadi Malek Bagomghaleh, Saeed Pishbin, Gholamhossein Gholami
Summary: This study combines the concept of vanishing delay arguments with a linear system of integral-algebraic equations (IAEs) for the first time. The piecewise collocation scheme is used to numerically solve the Hessenberg type IAEs system with vanishing delays. Well-established results regarding regularity, existence, uniqueness, and convergence of the solution are presented. Two test problems are studied to verify the theoretical achievements in practice.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Qi Hu, Tao Jin, Yulian Jiang, Xingwen Liu
Summary: Public supervision plays an important role in guiding and influencing individual behavior. This study proposes a reputation incentives mechanism with public supervision, where each player has the authority to evaluate others. Numerical simulations show that reputation provides positive incentives for cooperation.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Werner M. Seiler, Matthias Seiss
Summary: This article proposes a geometric approach for the numerical integration of (systems of) quasi-linear differential equations with singular initial and boundary value problems. It transforms the original problem into computing the unstable manifold at a stationary point of an associated vector field, allowing efficient and robust solutions. Additionally, the shooting method is employed for boundary value problems. Examples of (generalized) Lane-Emden equations and the Thomas-Fermi equation are discussed.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Lisandro A. Raviola, Mariano F. De Leo
Summary: We evaluated the performance of novel numerical methods for solving one-dimensional nonlinear fractional dispersive and dissipative evolution equations and showed that the proposed methods are effective in terms of accuracy and computational cost. They can be applied to both irreversible models and dissipative solitons, offering a promising alternative for solving a wide range of evolutionary partial differential equations.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Yong Wang, Jie Zhong, Qinyao Pan, Ning Li
Summary: This paper studies the set stability of Boolean networks using the semi-tensor product of matrices. It introduces an index-vector and an algorithm to verify and achieve set stability, and proposes a hybrid pinning control technique to reduce computational complexity. The issue of synchronization is also discussed, and simulations are presented to demonstrate the effectiveness of the results obtained.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Ling Cheng, Sirui Zhang, Yingchun Wang
Summary: This paper considers the optimal capacity allocation problem of integrated energy systems (IESs) with power-gas systems for clean energy consumption. It establishes power-gas network models with equality and inequality constraints, and designs a novel full distributed cooperative optimal regulation scheme to tackle this problem. A distributed projection operator is developed to handle the inequality constraints in IESs. The simulation demonstrates the effectiveness of the distributed optimization approach.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Abdurrahim Toktas, Ugur Erkan, Suo Gao, Chanil Pak
Summary: This study proposes a novel image encryption scheme based on the Bessel map, which ensures the security and randomness of the ciphered images through the chaotic characteristics and complexity of the Bessel map.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Xinjie Fu, Jinrong Wang
Summary: In this paper, we establish an SAIQR epidemic network model and explore the global stability of the disease in both disease-free and endemic equilibria. We also consider the control of epidemic transmission through non-instantaneous impulsive vaccination and demonstrate the sustainability of the model. Finally, we validate the results through numerical simulations using a scale-free network.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
Article
Mathematics, Applied
Maria Han Veiga, Lorenzo Micalizzi, Davide Torlo
Summary: The paper focuses on the iterative discretization of weak formulations in the context of ODE problems. Several strategies to improve the accuracy of the method are proposed, and the method is combined with a Deferred Correction framework to introduce efficient p-adaptive modifications. Analytical and numerical results demonstrate the stability and computational efficiency of the modified methods.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
