Natural Frequencies of Small Cylinders and Tubes
Journal Title: Problemy Mechatroniki. Uzbrojenie, lotnictwo, inżynieria bezpieczeństwa - Year 2015, Vol 6, Issue 2
Abstract
The paper deals with modal analysis of the cylinders and tubes and their mutual comparison. Nowadays, modal analysis is a powerful method of describing the vibration properties. When we know own shapes and natural frequencies, we can predict e.g. behaviour of tubes under loading conditions. The tubes dimensions were taken as dimensions which are close to assault rifle barrels. The same dimensions were taken for cylinders. The cylinders and tubes as 3D objects were modelled and their lengths and thicknesses were modified. Modal analysis was performed by LS-DYNA software using FEM with iterative Lanczos method. In Tables 1-12, the natural frequencies for these cantilever beams and their corresponding own shapes with modification in fixing length for three different thicknesses are listed. In Figure 2 and 7-9, these natural frequencies versus modification in fixing length for three different thicknesses for corresponding modes are shown. In Figure 3-5 and 10-12, natural frequencies versus length of cylinders and tubes for three different thicknesses for corresponding modes are shown.
Authors and Affiliations
Peter LISY
Badania wpływu kąta uderzenia 7,62 mm pocisku pistoletowego z rdzeniem ołowianym i płaszczem stalowym na penetrację wkładów balistycznych aramidowych i polietylenowych
W artykule zaprezentowano wyniki badań próbek wkładów podstawowych do kamizelek kuloodpornych. Prace ukierunkowane były na określenie wpływu kąta uderzenia pocisku na wartość granicy ochrony balistycznej. Stosowano 7,62...
PMN, PMN-2 and PMF-1 Landmines Detection Using Active Infrared Thermography with Microwave Excitation
In this paper, active infrared thermography is used to detect antipersonnel landmines: PMN, PMN-2 and PMF-1. Mentioned landmines have very low metal content and their casings are made of plastic, therefore are considered...
Measurements of Percussion Cap Parameters
Investigation results of percussion cap (KWM-3 as example) parameters such as initiation mean energy (130 mJ approx.), their standard deviation (30 mJ approx.) as well as delay time (450 s at an average), firing pin deep...
Rękawica rzeczywistości wirtualnej. Budowa systemu śledzenia ruchu ręki oraz palców wykorzystywanego w technice rzeczywistości wirtualnej
System śledzenia ruchu ręki oraz palców jest powszechnie stosowany w immersyjnych aplikacjach rzeczywistości wirtualnej umożliwiając użytkownikowi symulacji interaktywne uczestnictwo poprzez manipulację wirtualnymi przed...
Analysis of Aerodynamic Characteristics of the Rocket-Target for the „Stinger” System
This paper presents an analysis of aerodynamic characteristics of the rocket-target for the final training of shooting at aerial targets by the „Stinger” system service staff. The governing equations of fluid dynamics ar...