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Ing. Tomáš Padělek, Ph.D.

2021

Cílem studie je prověřit možnosti přepravy materiálu pro připravovanou výstavbu hráze Vodního díla Vlachovice na vodním toku Vlára.

2020, Book of abstract ESCO 2020, Plzeň, ZČU Plzeň)

This paper presents the numerical simulation of generalized Newtonian fluids flow in the bypass geometry. The considered geometry consists of the narrowed main tube and the bypass graft. The quality of the blood flow in the bypass can be influenced by a location of the narrowing or by the geometry. The optimal angle for the connecting of the bypass graft to the vessel is around 45 degrees, therefore this work is mentioned on the numerical modelling of the varied mathematical models of the viscosity with the angle of the connection 45 and 60 degrees. Our study is focused on testing different types of bypass geometry, standard and S-type bypass connections. As well as various narrowing of the problematic section in the main channel are presented. Symmetrical and unsymmetrical narrowing is tested for both types of bypass. The governing system of equations is based on the system of balance laws for mass and momentum. Generalized Newtonian fluids flow in the bypass is numerically simulated by using open source CFD tool, OpenFOAM with a SIMPLE algorithm.

2019, 2019 Smart City Symposium Prague, New York, IEEE Press), ISBN 978-1-7281-0497-3

The article presents results of testing of influence of design parameters on the road safety at roundabouts. Hypotheses about the influence of particular design parameters on the road safety were created and these were verified using traffic accident and traffic conflict data of roundabouts. This approach can help to define the safe extent of particular design parameters of a roundabout and increase the level of road safety consequently.

2019, Advances in Computational Mathematics, 45 (4), p. 2047-2063), ISSN 1019-7168

The following paper describes a numerical simulation of a complete bypass of a stenosed human artery. The considered geometry consists of the narrowed host tube and the bypass graft with a 45-degree angle of connection. Different diameters of the narrowing are tested. Blood is the fluid with shear rate-dependent viscosity; therefore, various rheology mathematical models for generalized Newtonian fluids are considered, namely Cross model, modified Cross model, Carreau model, and Carreau-Yasuda model. The fundamental system of equations is based on the system of generalized Navier-Stokes equations. Generalized Newtonian fluids flow in a bypass tube is numerically simulated by using a SIMPLE algorithm included in the open-source CFD tool, OpenFOAM. The aim of this work is to compare the numerical results for the different mathematical models of the viscosity with the changing diameter of the narrowed channel.

2019, Proceedings of Seminar Programs and Algorithms of Numerical Mathematics 19, Praha, Academy of Sciences of the Czech Republic), p. 63-70), ISBN 978-80-85823-69-1

The aim of this work is to present numerical results of non-Newtonian fluid flow in a model of bypass. Different angle of a connection between narrowed channel and the bypass graft is considered. Several rheology viscosity models were used for the non-Newtonian fluid, namely the modified Cross model and the Carreau-Yasuda model. The results of non-Newtonian fluid flow are compared to the results of Newtonian fluid. The fundamental system of equations is the generalized system of Navier-Stokes equations for incompressible laminar flow. Generalized Newtonian fluids flow in the bypass is numerically simulated by using an open source CFD tool, OpenFOAM.

2019, Journal of Physics: Conference Series, Bristol, IOP Publishing Ltd.), ISSN 1742-6596

This work presents the numerical solution of generalized Newtonian fluids in the bypass geometry. The considered geometry consists of the narrowed host tube and the bypass graft with 30, 45, 60 degrees angle of the connection. Two values of the Reynolds number, 100, 200, are tested. The numerical results of non-Newtonian fluids are compared to the results of Newtonian fluids. The governing system of equations is based on the system of balance laws for mass and momentum. Generalized Newtonian fluids flow in the bypass tube is numerically simulated by using SIMPLE algorithm included in OpenFOAM.

2018, 2018 Smart City Symposium Prague, New York, IEEE Press), p. 1-5), ISBN 978-1-5386-5017-2

The article presents a new approach to safety level assessment by conducting road safety inspections.

2018, Proceedings of the Conference on Modelling Fluid Flow (CMFF'18), Budapest, Budapest University of Technology and Economics), ISBN 978-963-313-297-5

This work examines the study of a complete bypass with a stenosed native artery. The fundamental system of equations is based on the system of Navier-Stokes equations. A Newtonian fluids flow in a bypass tube is numerically simulated by using the open source CFD tool, OpenFOAM and a SIMPLE (Semi Implicit Method for Pressure Linked Equations) algorithm for numerical solution is used. Numerical tests are conducted on a three dimensional geometry with a circle cross section. Dierent diameters of stenosis are tested and the numerical results for the described model of the bypass geometry are presented and discussed.