Combined mesh free method and mode matching approach for transmission loss predictions of expansion chamber silencers

In order to avoid the dependence of mesh method on grids, a 3D global weak-form mesh-free method (MFM) is applied to study the three-dimensional acoustic characteristics of silencers. For the expansion chamber silencers, the 3D acoustic modes are extracted and the transmission loss results are computed by using the 3D global weak-form (MFM), which is based on the radial basis function point interpolation method (RPIM) for calculating the shape functions and Galerkin method for discretizing the system equation. The first 15 order 3D acoustic modes and TL results of a special expansion chamber silencer are presented to validate the computational accuracy of the proposed technique, and the relative errors are controlled within 0.5% by comparing with the 3D finite element method (FEF) calculations. Additionally, the effects of axial modes on the acoustic characteristics are investigated, and the pass through frequencies can be eliminated to enhance the acoustic attenuation performance by locating the side branch outlet on the nodal lines of axial modes.

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The meshless analog equation method: a new highly accurate truly mesh-free method for solving partial differential equations

Boundary Elements and Other Mesh Reduction Methods XXVIII ◽

10.2495/be06002 ◽

2006 ◽

Cited By ~ 5

Author(s):

J. T. Katsikadelis

Keyword(s):

Partial Differential Equations ◽

Differential Equations ◽

Equation Method ◽

Partial Differential ◽

Analog Equation Method ◽

Mesh Free ◽

Mesh Free Method ◽

Analog Equation

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Reply to comments on ‘Transmission loss prediction on a single-inlet/double-outlet cylindrical expansion-chamber muffler by using the modal meshing approach’ (Appl. Acoust. Volume 69 (2007) pp. 173–178)

Applied Acoustics ◽

10.1016/j.apacoust.2007.07.005 ◽

2008 ◽

Vol 69 (3) ◽

pp. 282 ◽

Cited By ~ 2

Author(s):

H.B. Tang

Keyword(s):

Transmission Loss ◽

Expansion Chamber ◽

Loss Prediction

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Mesh-Free Method for Predicting the Behavior of Saturated Soil

Geomechanics ◽

10.1061/40797(172)39 ◽

2005 ◽

Cited By ~ 2

Author(s):

Akira Murakami ◽

Shin'ichi Arimoto ◽

Tatsuya Setsuyasu ◽

Tatsuro Nishiyama

Keyword(s):

Saturated Soil ◽

Mesh Free ◽

Mesh Free Method

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Parameter Identification by Inverse Analysis Coupled with a Finite Pointset Method for Polyurethane Foam Expansion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.611-612.868 ◽

2014 ◽

Vol 611-612 ◽

pp. 868-875 ◽

Cited By ~ 1

Author(s):

Hichem Abdessalam ◽

Boussad Abbès ◽

Yu Ming Li ◽

Ying Qiao Guo ◽

Elvis Kwassi ◽

...

Keyword(s):

Parameter Identification ◽

Reaction Temperature ◽

Inverse Analysis ◽

Stokes Equations ◽

Foam Height ◽

Test Tube ◽

Navier Stokes ◽

Foam Expansion ◽

Mesh Free ◽

Mesh Free Method

This paper deals with the parameter identification for polyurethane foaming process simulation by using an inverse analysis coupled with a Finite Pointset Method. Simultaneous measurements of the foam height rise, the reaction temperature and the viscosity on a cylindrical cardboard test tube are obtained by using the foam measurement system (FOAMAT). The simulation of the foam expansion is obtained by solving unsteady Navier-Stokes equations coupled with the energy equation, the curing reaction (reaction of isocyanate with polyol) and the foaming reaction (reaction of isocyanate with water to emit the CO2 gas) by using a mesh-free method. The inverse identification method consists in determining the parameters by comparing the computed quantities (height rise, reaction temperature and viscosity) computed by the finite pointset method to those measured experimentally.

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Approximation of the first eigenpair of the p(x)-Laplacian using WEB-spline based mesh-free method

Engineering Analysis with Boundary Elements ◽

10.1016/j.enganabound.2021.06.020 ◽

2021 ◽

Vol 131 ◽

pp. 269-279

Author(s):

Suchismita Patra ◽

Naraveni Rajashekar ◽

V.V.K. Srinivas Kumar

Keyword(s):

Mesh Free ◽

Mesh Free Method

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Modelling Closed-Die Forging Operations Using Total Lagrangian Smooth Particle Hydrodynamics

10.31224/osf.io/nbqjm ◽

2019 ◽

Author(s):

Anthony Manson

Keyword(s):

Large Deformation ◽

Smooth Particle Hydrodynamics ◽

Material Flows ◽

Forging Process ◽

Mesh Free ◽

Closed Die Forging ◽

Particle Hydrodynamics ◽

Mesh Free Method ◽

Large Material ◽

Simulation Parameters

Total Lagrangian Smooth Particle Hydrodynamics (TLSPH) has been applied to a set of non-trivial, commercially interesting forging examples.Being a mesh-free method, TLSPH can conveniently simulate processes having large deformation and material separation.Test cases were designed that were characterized by large material flows having large changes in grain connectivity.The implementation used, Smooth Mach Dynamics (SMD), provided tunable simulation parameters that enabled the simulation to optimally match each case.The results showed that the TLSPH/SMD has the potential to model the metal forging process efficiently without numerical instabilities.Each case studied required adaptation of the simulation parameters to optimize the results.

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A Numerical Method for SolvingTwo-Dimensional Nonlinear Parabolic ProblemsBased on a Preconditioning Operator

Mathematical Modelling and Analysis ◽

10.3846/mma.2020.4310 ◽

2020 ◽

Vol 25 (4) ◽

pp. 531-545

Author(s):

Amir Hossein Salehi Shayegan ◽

Ali Zakeri ◽

Seyed Mohammad Hosseini

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Parabolic Problem ◽

Time Variable ◽

Two Dimensional ◽

Helmholtz Operator ◽

Mesh Free ◽

Nonlinear Parabolic ◽

Spline Finite Element ◽

Mesh Free Method

This article considers a nonlinear system of elliptic problems, which is obtained by discretizing the time variable of a two-dimensional nonlinear parabolic problem. Since the system consists of ill-conditioned problems, therefore a stabilized, mesh-free method is proposed. The method is based on coupling the preconditioned Sobolev space gradient method and WEB-spline finite element method with Helmholtz operator as a preconditioner. The convergence and error analysis of the method are given. Finally, a numerical example is solved by this preconditioner to show the efficiency and accuracy of the proposed methods.

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