Search for dissertations about: "muffler"

Showing result 1 - 5 of 9 swedish dissertations containing the word muffler.

  1. 1. Investigation of perforated mufflers and plates

    University dissertation from Stockholm : KTH

    Author : Ying Guo; KTH.; [2009]
    Keywords : sound; perforated; micro-perforated; muffler; flow; hole; impedance; model; experiment;

    Abstract :   Mufflers are used in for instance exhaust system of cars or trucks to reduce noise.Perforated pipes are one of the main components of modern mufflers. To study acoustic properties of mufflers with perforated pipe is one of the main targets of this thesis. READ MORE

  2. 2. Acoustic source characterisation for non-linear in-duct sources

    University dissertation from Institutionen för farkostteknik

    Author : Fredrik Albertson; KTH.; [2001]
    Keywords : in-duct source; source characterisation; non-linear source; linearity test; hybrid method; IC-engine; muffler; coupling method;

    Abstract : Different ways to model acoustic in-duct sources have beenanalysed. Measurements were conducted on two diesel truckengines. It was found that for steady state oscillations, onecould linearise in the neighbourhood of a given linearisationpoint, i.e. READ MORE

  3. 3. Aeroacoustics Studies of Duct Branches with Application to Silencers

    University dissertation from Stockholm : KTH

    Author : Mikael Karlsson; KTH.; [2010]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silencer; muffler; confined flows; flow duct; aeroacoustics; vortex sound; acoustic multiports; linear stability; self-sustained oscillations; whistling; Herschel-Quincke tube; acoustic resonator; TECHNOLOGY Engineering mechanics Fluid mechanics; TEKNIKVETENSKAP Teknisk mekanik Strömningsmekanik;

    Abstract : New methodologies and concepts for developing compact and energy efficient automotive exhaust systems have been studied. This originates in the growing concern for global warming, to which road transportation is a major contributor. READ MORE

  4. 4. Investigation and Optimization of the Acoustic Performance of Exhaust Systems

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Sara Elsaadany; KTH.; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Exhaust systems; noise; pressure drop; 1D models; perforated mufflers; after treatment devices; optimization;

    Abstract : There is a strong competition among automotive manufacturers to reduce the radiated noise levels. One important source is the engine exhaust where the main noise control strategy is by using efficient mufflers. READ MORE

  5. 5. Analysis, Control, and Design Optimization of Engineering Mechanics Systems

    University dissertation from Umeå : Umeå University

    Author : Esubalewe Lakie Yedeg; Umeå universitet.; [2016]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Topology optimization; Helmholtz equation; acoustic impedance; anisotropic filter; thin structures; finite element method; Nitsche-type method; interface problem; Optimal control; adjoint method; Computing Science; administrativ databehandling;

    Abstract : This thesis considers applications of gradient-based optimization algorithms to the design and control of some mechanics systems. The material distribution approach to topology optimization is applied to design two different acoustic devices, a reactive muffler and an acoustic horn, and optimization is used to control a ball pitching robot. READ MORE