Methods of modeling of road’s infrastructure support elements

W pracy przedstawiono wybrane sposoby modelowania słupa wsporczego znaku drogowego w programie LS-Dyna. Podjęto próbę wykazania zalet i wad dla poszczególnych rozwiązań. Podczas analizy skupiono się na sposobie modelowania słupa, upraszczając pozostałe elementy konstrukcji w tym utwierdzenie w podłożu.This paper presents some ways of modeling the supporting pole for a traffic sign in the LS-Dyna. An attempt was made to demonstrate the advantages and disadvantages for each solution. Analysis is focused on the modeling method, whereas the the remaining elements of construction are simplified

Finite element analysis of ventilation system fire damper dynamic time-history

The paper presents results of the numerical analysis of the fire damper used in ventilation systems under the earthquake loading. The research was conducted in accordance with the recommendations of the Nuclear Safety Standards Commission. The aim of the analysis was to examine the fire damper with respect to its resistance to service loadings, structural integrity, and capability to stay operative after an earthquake. The analysis was carried out using the Finite Element Method in LS-Dyna software. The earthquake loading was modelled as accelerations, measured in three directions during the earthquake. For modelling of the materials behaviour, material models taking into account the influence of strain rate on hardening were used. The analysis consisted of three stages, which were: loading the construction with the earth gravity, earthquake simulation by loading with accelerations in three directions, and, finally, closing the fire damper. The analysis has shown that some of the construction elements undergo plastic deformations. However, the performed simulation of fire damper closing showed that despite these deformations, the device remains capable to keep its functionality and the damper closes hermetically. The results of the analysis were important design indications for the fire damper prototype

Numerical analysis of a ballistic test of a bullet cal. 7.92 × 33

W pracy przedstawiono analizę numeryczną testu balistycznego pocisku kalibru 7,92 × 33 przeprowadzoną na podstawie wytycznych norm opracowanych przez niemieckie towarzystwo VPAM. Test balistyczny polegał na penetracji przez pocisk płyty stalowej, wykonanej ze stali Weldox 700E o grubości 8 mm, w zależności od kąta natarcia. Analiza numeryczna dotyczyła weryfikacji literaturowych danych dotyczących kąta natarcia pocisku i skutecznej penetracji płyty stalowej.This paper presents some ways of modeling the bullet impact in the LS-Dyna. An attempt was made to verify the literature data the angle of impact of the projectile with the effective penetration of steel plate

Fatigue life prediction for acid-resistant steel plate under operating loads

The paper evaluates the causes related to the fatigue damage in a conveyor slide plate, exposed to high-frequency cyclic loads. The plate was made of 1.4301 acid-resistant steel. The fractography showed that the plate failure was caused by fatigue crack. A nonlinear analysis of plate deformation was conducted using the finite element method (FEA) in LS-Dyna software. The maximum normal stresses in the plate fracture were used in further analysis. A “fatigue limit” calculated initially using a FITNET procedure was above the maximum stress calculated using FEA. It indicates that the structural features of the plate were selected correctly. The experimental test results for 1.4301 acid-resistant steel were described using a probabilistic Weibull distribution model. Reliability was determined for the obtained S-N curve at 50% and 5% failure probability allowing for the selected coefficients (cycle asymmetry, roughness, variable load) and the history of cyclic loading. Cumulative damage was determined using the Palmgren-Miner hypothesis. The estimated fatigue life was similar to the actual value determined in the operating conditions for the S-N curve at 5% failure probability. For engineering calculations, the S-N curve at max. 5% failure probability is recommended

Cu-etp copper monotonic tensile test modeling in ls-dyna software using hardening and damage models

This paper deals with modeling of monotonic tensile test of Cu-ETP copper in numerical environment using finite element method. The research aims to verify the capabilities of LS-Dyna software in terms of modeling the strain hardening and damage of the material. The numerical analyses were proceeded by experimental tests to determine the materials constants of isotropic hardening model and constant required for modeling of material’s damage. Determined material constants were implemented into LS-Dyna environment using MAT_Damage_3 material model. The specimen model was built using eight-node hexahedrons. Both in case of experimental and numerical tests, the controlled parameter was displacement of the specimen. Obtained strain-stress curves were analyzed and conclusions were drawn