Browsing by Subject "numerical analysis"

Now showing 1 - 13 of 13

Access status: Open Access ,
Analiza oddziaływania posadowień nowych konstrukcji na istniejące obiekty podziemne
(Wydawnictwa AGH, 2010) Dąbska, Agnieszka; Popielski, Paweł; Fadeev, Aleksander D.; Gorodnova, Elena Vladimirovna
In the article there is discussed problem following to additional loadings, which is applied on stress-deformation condition existing in the ground. There are presented results of the numerical analysis of new object influence on underground constructions on several examples of objects realized in Poland (Warsaw): the tunnels and stations of the underground and Russia (Saint Petersburg): the main collectors of city in Saint Petersburg. The numerical analysis, based on finite elements methods, has been used for calculations, what allow to draw conclusion concerning the safe construction.
Access status: Open Access ,
Criterion for angle prediction for the crack in materials with random structure
(2011) Podgórski, Jerzy
Presented paper contains results of fracture analysis of brittle composite materials with a random distribution of grains. The composite structure has been modelled as an isotropic matrix that surrounds circular grains with random diameters and space position. Analyses were preformed for the rectangular 'numerical sample' by finite element method. FE mesh for the examples were generated using the authors' computer program RandomGrain. Fracture analyses were accomplished with the authors' computer program CrackPath3 executing the 'fine mesh window' technique. Calculations were preformed in 2D space assuming the plane stress state. Current efforts focus on brittle materials such as rocks or concrete.
Access status: Restricted ,
Eksperymentalne i numeryczne określanie charakterystyk wentylatora promieniowego transportującego powietrze do przestrzeni nieograniczonej
(Data obrony: 2015-07-20) Gorzała, Paweł
Wydział Energetyki i Paliw
Access status: Restricted ,
Eksperymentalne i numeryczne określenie charakterystyk wentylatora promieniowego w zabudowie kanałowej
(Data obrony: 2015-07-20) Mucha, Dariusz
Wydział Energetyki i Paliw
Access status: Open Access ,
Enhancing mesh adaptation capabilities of GetFEM++ “FEM engine” with MAdLib library
(2013) Perduta, Anna
This paper describes enhancing mesh adaptation capabilities of GetFEM++ library. GetFEM++ is a versetile software package in C++ for implementing FEM based solvers for partial differential equations. Although GetFEM++ offers a wide range of mathematic tools for model descripion and discretization, it does only provide basic mesh refinement facilities. To enhance GetFEM++ capabilities, a mesh adaptation package MAdLib is used. The paper discusses basic requirements for mesh adaptation packages and presents MAdLib basic usage. The paper discusses implementation issues related to integration of both libraries. Examples illustrate capabilities of mesh adapation package and FEM framework extended by mesh adaptation facilities.
Access status: Open Access ,
Grounds for the selection of software components for building FEM simulation systems for coupled problems
(2011) Putanowicz, Roman
This paper discusses rationales for selection of software components for building scientific simulation tools. Nowadays no single research team has the resources or knowledge to build non-trivial simulation software form scratch. Sharing experience about the motives behind the choice of software components and the consequences of particular decisions seems a valuable knowledge as it can help to avoid some potential traps. In the paper we discuss software selection decisions for our problem solving environment for numerical modelling of coupled problems. For selected tools we discuss pros and cons of their use and mention potential alternatives. The detailed discussion concerns implementation of a solver for thermoelasticity problems.
Access status: Open Access ,
Laser melted steel free surface formation
(2007) Siwek, Aleksander
Two-dimensional mathematical model of recasting steel by laser was presented in this paper. Surface velocity and liquid temperature for several powers of laser beams and sulfur contents were obtained as results of numerical modeling of liquid flow and heat exchange processes. The shape of free surface in a melted zone was computed with the use of iterative method proposed in this paper.
Access status: Open Access ,
Low frequency identification of critical states of transmission tower structures
(2013) Szopa, Krystian; Iwaniec, Marek; Gołaś, Andrzej
Transmission towers are vital parts of the overhead power line infrastructures. Any damage to these supporting structures may result in decreased load-bearing capacity and, in consequence, their collapse. Failures of transmission towers are much more severe than power failures, as they not only cause interruption to the energy supply but can also result in considerable costs of infrastructure repairs and damage. Therefore, supporting structures of overhead power lines should be subjected to structural health monitoring. This paper presents a comprehensive database containing natural frequencies and strain energies of all elements for various (simulated) damage states. On the basis of structure modal parameters, by finding the correlation between natural frequencies of damaged structure stored in the created database and natural frequencies of the structure of interest, state of the test structure can be identified. In order to verify this method, a numerical experiment was carried out. Observing the strain energy variation as compared to the undamaged state makes it possible to localize the damage and assess its importance for the further structure exploitation.
Access status: Restricted ,
Obliczanie i analiza charakterystycznych parametrów przebiegów okresowych
(Data obrony: 2018-07-13) Czerniawski, Adam
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
Access status: Restricted ,
Projekt wentylatora promieniowego w obudowie spiralnej
(Data obrony: 2015-10-26) Kleszcz, Sławosz
Wydział Energetyki i Paliw
Access status: Restricted ,
Rozwiązywanie prostych i odwrotnych zagadnień przewodzenia ciepła
(Wydawnictwa Naukowo-Techniczne, 2003) Taler, Jan; Duda, Piotr
Access status: Open Access ,
Shape prediction during the free forming process of semi-finished products electrodynamically worked
(Wydawnictwa AGH, 2007) Kot, Andrzej; Bednarczyk, Józef
Possibility of free forming for semi-finished products and giving them demanded shapes without presence of forming dies distinguish the electrodynamic method in relation to standard technologies of metal plastic working, because there are no difficulties of using punch - die instrumentations. The article presents considerations referred to prediction possibilities of final shape of pipe and flat semi-finished products electrodynamically formed without using forming dies.
Access status: Open Access ,
Some efficient seventh-order derivative-free families in root-finding
(2013) Soleymani, Fazlollah
The interest in efficient root-finding iterations is nowadays growing and influenced by the widespread use of high-speed computers. On the other hand, the calculation of derivatives is often hard, when the problems are formulated in terms of nonlinear equations and as a result, the importance of derivative-free methods emerges. For these reasons, some efficient three-step families of iterations for solving nonlinear equations are suggested, where the analytical proofs show their seventh-order error equations consuming only four function evaluations per iteration. We employ hard numerical test problems to illustrate the accuracy of the new methods from the families.