Simulacija mehanskih lastnosti ulitkov s poroznostjo na podlagi brezmrežne metode

Vuga, Gašper (author), Šarler, Božidar (mentor)

Pri izdelavi kovinskih ulitkov se lahko pojavi nezaželjena poroznost. Obravnava vsake pore posebej je pri dimenzioniranju ulitkov, nesmiselna, smiselno pa je uporabiti homogen material z efektivnimi mehanskimi lastnostmi. Ker sta oblika in delež poroznosti lahko zelo različna, se pojavi problem določevanja efektivnih mehanskih lastnosti. V okviru diplomskega dela smo razširili programsko okolje EDO_SP na uporabo računanja napetosti in deformacij domen z luknjami. Z uporabo lokalne kolokacijske metode z radialnimi baznimi funkcijami, implementirane v EDO_SP, smo določili odvisnost efektivnega Youngovega modula in efektivnega Poissonovega količnika s poroznostjo. Računali smo v približku ravninskega napetostnega stanja za pore krožnih oblik ter delež poroznosti do 30 %. Za izračun smo razvili algoritem, ki avtomatizirano postavlja točke po domeni neodvisno od velikosti in pozicije lukenj. Z uporabo tako izdelanega algoritma smo ugotovil, da se naša funkcija spreminjanja efektivnega Youngovega modula s poroznostjo dobro ujema s funkcijo, ki je v literaturi že poznana.

• Language: Slovenian
• Keywords: poroznost, teorija elastičnosti, brezmrežna numerična metoda, radialne bazne funkcije, efektivne mehanske lastnosti, programski jezik Fortran 2008
• Work type: Bachelor thesis/paper
• Organization: FS - Faculty of Mechanical Engineering
• Year: 2017
• PID: 20.500.12556/RUL-95494
• Publication date in RUL: 20.09.2017

VUGA, Gašper, 2017, Simulacija mehanskih lastnosti ulitkov s poroznostjo na podlagi brezmrežne metode [online]. Bachelor’s thesis. [Accessed 6 June 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=95494

Secondary language

• Language: English
• Title: Simulation of the mechanical properties of castings with porosity based on meshless method

Abstract

In manufacturing of metal casts defects like porosity can occur. It is not reasonable to include each pore in simulation. Instead, the exact description is replaced by effective mechanical properties, which we aim to calculate in this work. As the shape and the distribution of pores can vary substantially, it is difficult to determine effective mechanical properties. In this work, we have expanded the software environment EDO_SP so that it can be used for calculations of stresses and deformations on domains with holes. Using local collocation method with radial basis functions implemented in EDO_SP we have determined the dependence of the effective Young's modulus, and the effective Poisson's ratio on the porosity. Calculations have been performed in plane stress approximation for circular pores and for pore fractions up to 30 %. To perform the calculations, an algorithm for automatic node generation in computational domain that contains randomly positioned and variably-sized pores was developed. Using this algorithm we ascertained that the obtained relation between the effective Young's modulus and the porosity matches well the relation documented in existing research.

• Keywords: porosity, theory of elasticity, meshless numerical method, radial basis functions, effective mechanincal properties, coding language Fortran 2008