Damping Influence of System Vibration

2011 ◽  
Vol 71-78 ◽  
pp. 1889-1892
Author(s):  
Min Yuan Huang
Keyword(s):  
Free Vibration ◽  
Low Frequency ◽  
Harmonic Excitation ◽  
External Condition ◽  
Vibration Characteristics ◽  
Parameter Determination ◽  
Damping Factor ◽  
Fundamental Vibration ◽  
Frequency Effects ◽  
System Vibration

Regarding the system vibration as the research object, we study vibration characteristics of the system vibration under the damping action. The primary coverage is as follows: under the external condition of undamped condition, damping condition, free vibration, and harmonic excitation, etc., the fundamental vibration form possesses vibration characteristics. In the project practice, the damping factor’s role to the vibrating system, as well as parameter determination is the damping factor. Low frequency effects on the structure system along with the effective of controlling resonance. In the damping treatment, we have characteristics demand for the damping. Through thorough analysis to damping action, we will obtain the best project fitting.

Improvement of the mechanical and damping behavior of nylon by integration of nanoclay platelets

2021 ◽  
Vol 63 (12) ◽  
pp. 1124-1129
Author(s):  
Hari Bodipatti Subburamamurthy ◽  
Rajasekar Rathanasamy ◽  
Harikrishna Kumar Mohan Kumar ◽  
Moganapriya Chinnasamy ◽  
Gobinath Velu Kaliyannan ◽  
...  
Keyword(s):  
Free Vibration ◽  
Nylon 6 ◽  
Vibration Characteristics ◽  
Damping Factor ◽  
Melt Mixing ◽  
Weight Percentage ◽  
Specific Strength ◽  
Damping Behavior ◽  
Cloisite 30B ◽  
Fail Safe

Abstract Nylon is used as a gear material thanks to its beneficial characteristics, such as self-lubrication, noiseless and fail-safe operation. Poor resistance to heat, dimensional stability, shock and impact loads are major drawbacks of nylon when used in engineering applications. The addition of a nanofiller to a nylon matrix can enhance its mechanical and vibrational properties. Montmorillonite nanoclay (Cloisite 15 A, Cloisite 20 A and Cloisite 30B) modified with ammonium salt was incorporated into the Nylon 6 matrix by solution mixing and melt mixing. Nanoclay with 1, 2 and 3 wt.-% were added to the nylon matrix and the resulting mechanical and free vibration characteristics were determined. The experimental results of the mechanical and free vibration behavior were compared with the ANSYS results. Tensile strength, modulus of elasticity, specific strength, specific stiffness, natural frequency and damping factor were found to increase as the weight percentage of the nanoclay in the nylon matrix increased. Cloisite 30B nanocomposite shows better mechanical and free vibration characteristics when compared with pure Nylon 6, Cloisite 15 A and Cloisite 20 A nanocomposites. The Cloisite 30B nano-composite was prepared with 2 wt.-% shows maximum mechanical and free vibration performance.

Real Ear Sound Pressure Levels Developed by Three Portable Stereo System Earphones

1992 ◽  
Vol 1 (4) ◽  
pp. 52-55 ◽  
Author(s):  
Gail L. MacLean ◽  
Andrew Stuart ◽  
Robert Stenstrom
Keyword(s):  
High Frequency ◽  
Sound Pressure ◽  
Low Frequency ◽  
Test System ◽  
Output Frequency ◽  
Frequency Effects ◽  
Adult Men ◽  
Frequency Responses ◽  
Significant Difference ◽  
Sound Pressure Levels

Differences in real ear sound pressure levels (SPLs) with three portable stereo system (PSS) earphones (supraaural [Sony Model MDR-44], semiaural [Sony Model MDR-A15L], and insert [Sony Model MDR-E225]) were investigated. Twelve adult men served as subjects. Frequency response, high frequency average (HFA) output, peak output, peak output frequency, and overall RMS output for each PSS earphone were obtained with a probe tube microphone system (Fonix 6500 Hearing Aid Test System). Results indicated a significant difference in mean RMS outputs with nonsignificant differences in mean HFA outputs, peak outputs, and peak output frequencies among PSS earphones. Differences in mean overall RMS outputs were attributed to differences in low-frequency effects that were observed among the frequency responses of the three PSS earphones. It is suggested that one cannot assume equivalent real ear SPLs, with equivalent inputs, among different styles of PSS earphones.

Energy Balancing Method to Identify Nonlinear Damping of Bolted-Joint Interface

2016 ◽  
Vol 693 ◽  
pp. 318-323 ◽  
Author(s):  
Xin Liao ◽  
Jian Run Zhang
Keyword(s):  
Dry Friction ◽  
Harmonic Excitation ◽  
Joint Interface ◽  
Damping Factor ◽  
Viscous Damping ◽  
Bolted Joint ◽  
Energy Balancing ◽  
Stick Slip ◽  
Non Linear ◽  
Linear Damping

The interface of bolted joint commonly focuses on the research of non-linear damping and stiffness, which affect structural response. In the article, the non-linear damping model of bolted-joint interface is built, consisting of viscous damping and Coulomb friction. Energy balancing method is developed to identify the dry-friction parameter and viscous damping factor. The corresponding estimation equations are acquired when the input is harmonic excitation. Then, the vibration experiments with different bolted preloads are conducted, from which amplitudes in various input levels are used to work out the interface parameters. Also, the fitting curves of dry-friction parameters are also obtained. Finally, the results illustrate that the most interface of bolted joint in lower excitation levels occurs stick-slip motion, and the feasibility of the identification approach is demonstrated.

The Dynamics of Towed Arrays

1989 ◽  
Vol 111 (3) ◽  
pp. 208-213 ◽  
Author(s):  
G. S. Triantafyllou ◽  
C. Chryssostomidis
Keyword(s):  
Iterative Procedure ◽  
Cross Flow ◽  
Low Frequency ◽  
Harmonic Excitation ◽  
Fluid Forces ◽  
Damped System ◽  
Equivalent Linear ◽  
Quadratic Drag ◽  
Linear Damping ◽  
Towed Arrays

A procedure for calculating the response of an array to a harmonic excitation applied at the upstream end is presented. The fluid forces on the array are modeled following the slender-body approximation and the cross-flow principle. An equivalent linear damping is used to replace the quadratic drag due to cross-flow separation. The equivalent linear damping is determined using an iterative procedure. Numerical and asymptotic solutions are derived, and the response of a typical long array is calculated. It is found that, when the separation drag is included, the array exhibits the behavior of an over-damped system, responding only to low-frequency excitations.

The driving frequency effects on the atmospheric pressure corona jet plasmas from low frequency to radio frequency

2011 ◽  
Vol 18 (4) ◽  
pp. 043503 ◽  
Author(s):  
Dan Bee Kim ◽  
H. Jung ◽  
B. Gweon ◽  
S. Y. Moon ◽  
J. K. Rhee ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Atmospheric Pressure ◽  
Low Frequency ◽  
Driving Frequency ◽  
Frequency Effects
Sign in / Sign up

Export Citation Format

Share Document