scholarly journals Noise simulation and low noise design of skinned panel structure of scientific experiment rack

2021 ◽  
Vol 336 ◽  
pp. 01002
Author(s):  
Changshuai Yu ◽  
Zhong Luo ◽  
Haitao Luo ◽  
Siwei Guo ◽  
Guangming Liu ◽  
...  
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Low Noise ◽  
Vibration Response ◽  
Radiated Noise ◽  
Plate Structure ◽  
Scientific Experiment ◽  
Low Noise Design ◽  
The Finite Element Model

The noise of the scientific experiment rack radiates into the space station through the skinned structure, which directly affects the safety and health of astronauts in orbit for a long time, so it is necessary to carry out low-noise design. Firstly, the finite element model of the panel structure is established, and the correctness of the model is verified by modal test. Secondly, select a point as the vibration excitation point on the finite element model of the plate structure to simulate the vibration input of the excitation source, obtain its vibration response through the modal superposition method, take the vibration response as the boundary condition of the acoustic boundary element, use the modal acoustic transfer vector technology to calculate the radiation noise of the plate structure, and verify it through the noise test in the half anechoic chamber. Then, the acoustic pressure contribution analysis of the radiated noise from the skinned panel structure is carried out, and the panel area which can reduce the radiated noise of the target is determined. The constrained damping layer is applied in this area. The results show that the radiated noise at the target position is significantly reduced.

Study on Random Vibration Response Analysis for the Sphere Cylinder Assembly in Aerospace Vehicle

2014 ◽  
Vol 680 ◽  
pp. 258-262
Author(s):  
De Lin Sun ◽  
Zhe Zhao ◽  
Kun He ◽  
Ri Dong Liao
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Basic Principle ◽  
Random Vibration ◽  
Structural Strength ◽  
Element Model ◽  
Vibration Response ◽  
Response Analysis ◽  
Vibration Load ◽  
The Finite Element Model

To assess the structural strength of spherical cylinder, the finite element model was constructed by the NX NASTRAN software. Firstly,the basic principle of random vibration response analysis was introduced, then the random vibration response analysis of the cylinder assembly was analyzed. The simulation result shows that the stress of the joint between spherical cylinder clamp and the base is larger than other areas in conditions of a given random vibration load. The spherical cylinder structure is safe and that the maximum RMS stress is about 20 MPa.

scholarly journals Study on torsional vibration of RT60 crane transmission system

2020 ◽  
Vol 21 (2) ◽  
pp. 210
Author(s):  
Nengqi Xiao ◽  
Xiang Xu ◽  
Ruiping Zhou
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Torsional Vibration ◽  
Discrete Model ◽  
Element Model ◽  
Transmission System ◽  
Low Noise ◽  
Parameter Method ◽  
Elastic Coupling ◽  
The Finite Element Model

In the process of engineering use, the elastic coupling of the RT60 crane transmission system has a large noise and even breaks down sometimes. In this paper, RT60 crane transmission system is the research object. A finite element model and a discrete model for torsional vibration of transmission system are established by finite element method and lumped parameter method. Through the study of the finite element model and the vibration test of transmission system, the correctness of the system model, equivalent parameter, calculation method and MATLAB program are verified. Because of the high efficiency of the torsional vibration discrete system, the discrete model is used in this paper to replace the finite element model. The free vibration and response vibration of the crane transmission system are calculated and analyzed, and the reasons for the existence of the system noise are explained in the starting stage. Through the study of the vibration theory and the matching method of the elastic coupling, the CX-45-VFA-60-11 elastic coupling is proposed to replace the CX-45-VFA-11 elastic coupling. In this paper, the data signal is collected by the hall gear sensor, and the data are analyzed by the self-developed vibration tester. The vibration amplitude of the torsional vibration of the crane transmission system is greatly reduced by testing the transmission system of the replacement of the elastic coupling. This paper provides a theoretical guiding significance for the low noise design of the crane transmission system.

scholarly journals Sensitivity Analysis of the Influence of Structural Parameters on Dynamic Behaviour of Highly Redundant Cable-Stayed Bridges

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
B. Asgari ◽  
S. A. Osman ◽  
A. Adnan
Keyword(s):  
Sensitivity Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Model Updating ◽  
Structural Parameters ◽  
Element Model ◽  
Structural Behavior ◽  
Model Tuning ◽  
The Finite Element Model ◽  
Cable Stayed Bridges

The model tuning through sensitivity analysis is a prominent procedure to assess the structural behavior and dynamic characteristics of cable-stayed bridges. Most of the previous sensitivity-based model tuning methods are automatic iterative processes; however, the results of recent studies show that the most reasonable results are achievable by applying the manual methods to update the analytical model of cable-stayed bridges. This paper presents a model updating algorithm for highly redundant cable-stayed bridges that can be used as an iterative manual procedure. The updating parameters are selected through the sensitivity analysis which helps to better understand the structural behavior of the bridge. The finite element model of Tatara Bridge is considered for the numerical studies. The results of the simulations indicate the efficiency and applicability of the presented manual tuning method for updating the finite element model of cable-stayed bridges. The new aspects regarding effective material and structural parameters and model tuning procedure presented in this paper will be useful for analyzing and model updating of cable-stayed bridges.

Biodynamics of Human Thorax With Body Armors Subject to Bullet Impact

2001 ◽  
Author(s):  
Y. W. Kwon ◽  
J. A. Lobuono
Keyword(s):  
Experimental Data ◽  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Body Armor ◽  
Projectile Impact ◽  
Human Thorax ◽  
Trachea And Bronchi ◽  
Armor System ◽  
The Finite Element Model

Abstract The objective of this study is to develop a finite element model of the human thorax with a protective body armor system so that the model can adequately determine the thorax’s biodynamical response from a projectile impact. The finite element model of the human thorax consists of the thoracic skeleton, heart, lungs, major arteries, major veins, trachea, and bronchi. The finite element model of the human thorax is validated by comparing the model’s results to experimental data obtained from cadavers wearing a protective body armor system undergoing a projectile impact.

Dynamic Analysis of a Turbocharger Centrifugal Compressor Impeller

1991 ◽  
Author(s):  
V. Ramamurti ◽  
D. A. Subramani ◽  
K. Sridhara
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Centrifugal Compressor ◽  
Element Model ◽  
Simplified Model ◽  
Cyclic Symmetry ◽  
Compressor Impeller ◽  
Cyclic Symmetric ◽  
The Finite Element Model

Abstract Stress analysis and determination of eigen pairs of a typical turbocharger compressor impeller have been carried out using the concept of cyclic symmetry. A simplified model treating the blade and the hub as isolated elements has also been attempted. The limitations of the simplified model have been brought out. The results of the finite element model using the cyclic symmetric approach have been discussed.

Analysis of Effective Pre-Stress of Continuous Rigid Frame Bridge in Service Based on Inversion Theory

2013 ◽  
Vol 671-674 ◽  
pp. 1012-1015
Author(s):  
Zhao Ning Zhang ◽  
Ke Xing Li
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Inversion Method ◽  
Vertical Deflection ◽  
Continuous Rigid Frame Bridge ◽  
Rigid Frame ◽  
Inversion Theory ◽  
Rigid Frame Bridge ◽  
The Finite Element Model

Due to the environment, climate, loads and other factors, the pre-stress applied to the beam is not a constant. It is important for engineers to track the state of the pre-stress in order to ensure security of the bridge in service. To solve the problem mentioned above, the paper puts forward a new way to analyze the effective pre-stress using the displacement inversion method based on the inversion theory according to the measured vertical deflection of the bridge in service at different time. The method is a feasible way to predict the effective pre-stress of the bridge in service. Lastly, taking the pre-stressed concrete continuous rigid frame bridge for example, the effective pre-stress is analyzed by establishing the finite element model.

scholarly journals Physical Principles of a Piezo Accelerometer Sensitive to a Nearly Constant Signal

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3258 ◽  
Author(s):  
Valery Gupalov ◽  
Alexander Kukaev ◽  
Sergey Shevchenko ◽  
Egor Shalymov ◽  
Vladimir Venediktov
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Frequency Band ◽  
Linear Acceleration ◽  
High Sensitivity ◽  
Element Model ◽  
Wide Frequency Band ◽  
Piezoelectric Accelerometer ◽  
The Finite Element Model ◽  
Physical Principles

The paper considers the construction of a piezoelectric accelerometer capable of measuring constant linear acceleration. A number of designs are proposed that make it possible to achieve high sensitivity with small dimensions and a wide frequency band (from 10−5 Hz). The finite element model of the proposed design was investigated, and its output characteristic and scale factor (36 mV/g) were obtained.

Analysis on sealing performance of VL seals based on mixed lubrication theory

2019 ◽  
Vol 71 (1) ◽  
pp. 54-60 ◽  
Author(s):  
Shixian Xu ◽  
Zhengtao Su ◽  
Jian Wu
Keyword(s):  
Finite Element ◽  
Film Thickness ◽  
Finite Element Model ◽  
Friction Factor ◽  
Contact Pressure ◽  
Element Model ◽  
Mixed Lubrication ◽  
Content Type ◽  
Deformation Mechanics ◽  
The Finite Element Model

Purpose This paper aims to research the influence of pressure, friction factors, roughness and actuating speed to the mixed lubrication models of outstroke and instroke. Design/methodology/approach Mixed lubrication model is solved by finite volume method, which consists of coupled fluid mechanics, deformation mechanics and contact mechanics analyses. The influence of friction factor on the finite element model is also considered. Then, contact pressure, film thickness, friction and leakage have been studied. Findings It was found that the amount of leakage is sensitive to the film thickness. The larger the film thickness is, the greater the influence received from the friction factor, however, the effect of oil film on the friction is negligible. The friction is determined mainly by the contact pressure. The trend of friction and leakage influenced by actuating velocity and roughness is also obtained. Originality/value The influence of friction factor on the finite element model is considered. This can make the calculation more accurate.

scholarly journals Co-Simulation of an Inverter Fed Permanent Magnet Synchronous Machine

2014 ◽  
Vol 6 (1) ◽  
pp. 19-25
Author(s):  
Gergely Máté Kiss ◽  
István Vajda
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Analytical Model ◽  
Element Model ◽  
Electrical Machine ◽  
Permanent Magnet Synchronous Machine ◽  
Variable Speed ◽  
Analytical Variable ◽  
Drive Model ◽  
The Finite Element Model

Abstract Co-simulation is a method which makes it possible to study the electric machine and its drive at once, as one system. By taking into account the actual inverter voltage waveforms in a finite element model instead of using only the fundamental, we are able to study the electrical machine's behavior in more realistic scenario. The recent increase in the use of variable speed drives justifies the research on such simulation techniques. In this paper we present the co-simulation of an inverter fed permanent magnet synchronous machine. The modelling method employs an analytical variable speed drive model and a finite element electrical machine model. By linking the analytical variable speed drive model together with a finite element model the complex simulation model enables the investigation of the electrical machine during actual operation. The methods are coupled via the results. This means that output of the finite element model serves as an input to the analytical model, and the output of the analytical model provides the input of the finite element model for a different simulation, thus enabling the finite element simulation of an inverter fed machine. The resulting speed and torque characteristics from the analytical model and the finite element model show a good agreement. The experiences with the co-simulation technique encourage further research and effort to improve the method.

Sign in / Sign up

Export Citation Format

Share Document