0715 Materials Handling Work Analysis of Crawler Cranes by Three-Dimensional Virtual Simulator (Dynamic Behavior of a Crane in Jib Luffing)

2013 ◽  
Vol 2013.50 (0) ◽  
pp. 071501-071502
Author(s):  
Chikara NAKAGAWA ◽  
Masajiro ABE ◽  
Toshikazu FUJINO
Keyword(s):  
Dynamic Behavior ◽  
Three Dimensional ◽  
Work Analysis ◽  
Materials Handling

Modeling and simulation of the dynamic behavior of the macaw palm fruit-rachilla system

SIMULATION ◽  
2021 ◽  
pp. 003754972110437
Author(s):  
Mariana Ribeiro Pereira ◽  
Fábio Lúcio Santos ◽  
Nara Silveira Velloso ◽  
Flora Maria de Melo Villar ◽  
Mateus Resende Rodrigues
Keyword(s):  
Dynamic Behavior ◽  
Elasticity Modulus ◽  
Natural Frequencies ◽  
Three Dimensional ◽  
Palm Tree ◽  
Specific Mass ◽  
Palm Fruit ◽  
Modes Of Vibration ◽  
Macaw Palm ◽  
Three Dimensional Models

The macaw palm ( Acrocomia aculeata) is a palm tree native to tropical forests that stand out due to its great potential for oil production. This study was developed with the objective of constructing a high-fidelity model of the macaw palm fruit-rachilla system for the purpose of simulating its dynamic behavior when subjected to mechanical vibrations. The finite element method was used to determine the natural frequencies and modes of vibration of the system. The three-dimensional models of the fruit-rachilla systems were elaborated using CAD3D Fusion 360 software. The modal properties of the fruit-rachilla systems were obtained based on the models developed by varying the elasticity modulus values of the system. The parameters of greatest influence in the estimation of natural frequencies are the elasticity modulus, especially that of the fruit-rachilla joint, and the specific mass. The models that take into account the three-dimensional strains along the rachilla are the least sensitive to variations in the mechanical properties (elasticity modulus and specific mass) and are shown to be more representative of the actual physical system.

Wave Propagation Analysis of Piping Structures

2009 ◽  
Author(s):  
Akemi Nishida
Keyword(s):  
Wave Propagation ◽  
Dynamic Behavior ◽  
Nuclear Power ◽  
Power Plants ◽  
Three Dimensional ◽  
Beam Theory ◽  
Spectral Element ◽  
Analysis Tool ◽  
Propagation Analysis ◽  
Piping Systems

It is becoming important to carry out detailed modeling procedures and analyses to better understand the actual phenomena. Because some accidents caused by high-frequency vibrations of piping have been recently reported, the clarification of the dynamic behavior of the piping structure during operation is imperative in order to avoid such accidents. The aim of our research is to develop detailed analysis tools and to determine the dynamic behavior of piping systems in nuclear power plants, which are complicated assemblages of different parts. In this study, a three-dimensional dynamic frame analysis tool for wave propagation analysis is developed by using the spectral element method (SEM) based on the Timoshenko beam theory. Further, a multi-connected structure is analyzed and compared with the experimental results. Consequently, the applicability of the SEM is shown.

Three-Dimensional Dynamic Model of TEHD Tilting-Pad Journal Bearing—Part I: Theoretical Modeling

2015 ◽  
Vol 137 (4) ◽  
Author(s):  
Junho Suh ◽  
Alan Palazzolo
Keyword(s):  
Heat Conduction ◽  
Dynamic Model ◽  
Dynamic Behavior ◽  
Journal Bearing ◽  
Three Dimensional ◽  
Physical Parameters ◽  
Tilting Pad ◽  
Fluid Film Thickness ◽  
Three Dimensional Finite Element ◽  
Tilting Pad Journal Bearing

This paper is focused on a new modeling method of three-dimensional (3D) thermo-elasto-hydro-dynamic (TEHD) cylindrical pivot tilting-pad journal bearing (TPJB). Varying viscosity Reynolds equation and 3D energy equation are coupled via lubricant temperature and viscosity relationship. Three-dimensional finite element method (FEM) is adopted for the analysis of: (1) heat conduction in shaft and bearing pad, (2) thermal deformation of shaft and pad, (3) flexible bearing pad dynamic behavior, and (4) heat conduction, convection, and viscous shearing in thin lubricant film. For the computational efficiency, modal coordinate transformation is utilized in the flexible pad dynamic model, and pad dynamic behavior is represented only by means of modal coordinate. Fluid film thickness is calculated by a newly developed node based method, where pad arbitrary thermal and elastic deformation and journal thermal expansion are taken into account simultaneously. The main goal of this research is to provide more accurate numerical TPJB model than developed before so that the designers of rotating machinery are able to understand the bearing dynamic behavior and avoid unpredicted problem by selection of physical parameters.

2C35 Work Analysis of Heart based on Three-dimensional Cardiac shape image

2001 ◽  
Vol 2001.12 (0) ◽  
pp. 203-204
Author(s):  
Hidenori HIGASHI ◽  
Yutaka SAWAKI ◽  
Masataka TOKUDA ◽  
Tadashi INABA ◽  
Kazuo YAGI
Keyword(s):  
Three Dimensional ◽  
Work Analysis

Three-Dimensional Spinal Loading during Complex Lifting Tasks

1996 ◽  
Vol 40 (13) ◽  
pp. 661-665
Author(s):  
Fadi A. Fathallah ◽  
William S. Marras ◽  
Mohamad Parnianpour
Keyword(s):  
Three Dimensional ◽  
Comprehensive Treatment ◽  
Shear Forces ◽  
Spinal Loading ◽  
Materials Handling ◽  
Spinal Loads ◽  
Loading Patterns ◽  
Temporal Occurrence ◽  
Asymmetric Lifting

Knowledge of the complex three-dimensional loads imposed on the spine during typical manual materials handling (MMH) tasks could provide more insights about the mechanical etiology of low back injuries in occupational settings. Comprehensive treatment of such information has been lacking. Most previous studies quantified spinal loading in terms of compressive forces alone. However, there is enough empirical and epidemiological evidence to indicate that the shear forces imposed on the spine may be more important than mere compression. Hence, the purpose of this study was to assess, in-vivo, the three-dimensional complex spinal loading associated with lifting tasks. Subjects performed simulated lifting tasks with varying workplace characteristic. An EMG-assisted model provided the continuous three-dimensional spinal loads. Asymmetric (complex) lifting tasks showed distinctive loading patterns from those observed under symmetric conditions. Simultaneous occurrences of spinal loads in all three directions (compression and shear forces) were patterns unique under the “risky” asymmetric lifting conditions. These situations could be identified and abated through proper workplace design. In conclusion, this approach allow the determination of the magnitudes and temporal occurrence(s) of complex spinal loading, and assess the sensitivity of these loading patterns to workplace characteristics.

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