消音器

BLUETD

一个关于消音器的资料

初到贵地

先友情帮顶
下载学习
学习后再跟楼主交流
谢谢！！！

hongfeng710

好资料，找了很久了。

liuwenwen612

请问有没有关于汽车排气系统振动噪声的资料啊！我的毕业设计是关于这个的，不知道从何着手

血影舞者

谢谢楼主分享，正在做有关消声器的课题。

ldh158

好资料就不要用几分了。分享就是让大家免费观看的。论坛真实的。

cx243360663

hao dong dong ..

liweizhao

有关于消音器防腐的资料吗？急需啊

chinali

有没有有关消声器的振动耐久性的测试实验的资料，有的话希望各位发一发，在此感激不尽

lvjintao

SYSNOISE
Analysis ofExhaust Noise
Excitation and Emitted Sound
A Numerical Tool for Each Problem
Model Features
Review of the Available Tools
Harmonic Uncoupled Analysis
Harmonic Coupled Analysis
Transient Analysis
Flow Effects
An Example : Full Double Exhaust Line
SYSNOISE Users for Duct Acoustics
Conclusion
Excitation
engine pulsation
mount vibration
Tailpipe Noise
purely acoustical
usually characterized by
dB attenuation, TL, IL
field point pressure
Shell Noise
induced by the shell vibration
usually characterized by
3D directivity pattern, field point pressure + radiated power

Tailpipe noise
uncoupled acoustic FE
uncoupled acoustic BE
coupled acoustic FE - acoustic BE
multi-domain acoustic BE
transient response using acoustic FE
extension to flow acoustics using acoustic FE
Shell noise
coupled acoustic FE - structural FE (followed by uncoupled BE)
coupled acoustic BE - structural FE
Both together
coupled acoustic BE - structural FE
Excitation
Pressure or velocity BC’s (inlet section)
Load or displacement BC’s (mounts)
Acoustic Properties
Temperature gradients
Volume absorbent material
Surface absorption
Open outlet end
Perforated pipes
Structural Properties
Normal structural modes
Shell behavior
Volume discretization
Heterogeneous fluid
temperature gradients
volume absorbent material
Pressure and velocity BCs (inlet section)
Impedance (admittance) BCs
open outlet end (e.g. Levine and Schwinger)
surface absorption
Perforated pipes
Acoustic modes (real or complex)
Forced response
Surface discretization
Homogeneous fluid
Pressure and velocity BCs (section inlet)
Impedance (admittance) BCs
surface absorption
Exact open outlet end
Perforated pipes
Forced response
Inside : Acoustic FE
Volume discretization
Temperature gradients
Absorbent material
Pressure and velocity BCs
Impedance BCs for surface absorption
Perforated pipes
Outside : Acoustic BE
Surface discretization (envelope of the muffler)
Homogeneous
Continuity (link) relations
        => Coupled Acoustic FE + Acoustic BE
Each domain characterized by
Direct (element) BE
Surface discretization
Homogeneous
Pressure and velocity BCs
Impedance BCs
Automatic link
Forced response
Benefits
Exact outlet end impedance
Sparse system of equations
Multiple fluids
Volume discretization
Heterogeneous
temperature gradients
Pressure and acceleration BCs
Impedance BCs for :
open outlet end
surface absorption
Transient response
2-step approach
stationary flow field (Laplace equation)
acoustic field (convected wave equation)
Flow field
flow potential and flow velocity BCs
frequency independent
Acoustic field
influenced by flow field
pressure, velocity and impedance BCs
frequency domain
Coupled Acoustic FE + Structural FE (followed by uncoupled Acoustic BE)
all features of FE (except flow)
interior coupled FE-FE => shell displacements
automatic conversion of shell displacements into velocity BCs
exterior uncoupled BE
only shell noise
Coupled Acoustic BE + Structural FE
exact open outlet end
homogeneous fluid
full problem solved in one step
both shell and/or tailpipe noise

Model courtesy of Bosal
Acoustic FE :
46.966 nodes
39.254 elements
Sound pulsation
2 inlet pipes
phase difference: 180 degrees
Rigid walls
Strong temperature gradient (500 0C -> 50 0C)
Vehicle manufacturers
Cars : CRF, Ford, GM, Renault, Rover,...
Trucks : Renault VI, IVECO, Asia Motors,...
Exhaust system manufacturers
Arvin, Bosal, E.C.I.A., Friedrich Boysen,...
Others
Compressors : TEE, LG Electronics, Embraco, ...
Ducts : A. Boet
Cowl silencers: Philips and Temro
Split silencers: Samsung HI,...
Exhaust Noise Problems
Tailpipe noise
Shell noise
Wide range of tools in SYSNOISE
Temperature gradients
Volume absorbent material
Surface absorption
Open outlet end
Perforated pipes
Flow effects
A Tool for Each Problem
Real-Life Problems


大家挣点分数不容易，是否有用，大家自己看着办，是个PPT。

20071602102

真希望是图纸

sdlgdx2002

thks  good document for muffler

yueguiping

学习学习,侃侃!!

9303497sy

撒东东啊  

chinali

都是关于声学等性的呀，咋没关于振动特性分析的能