Sökning: "intake noise"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden intake noise.

  1. 1. Modelling of IC-Engine Intake Noise

    Författare :Magnus Knutsson; Mats Åbom; Yves Auregán; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IC-engine; intake noise; gas dynamics; linear source data; frequency domain; 2-port; losses; air cleaner unit; filter paper; flow; FEM; BEM; charge air cooler; narrow tube; Acoustics; Akustik;

    Sammanfattning : Shorter product development cycles, densely packed engine compartments and intensified noiselegislation increase the need for accurate predictions of IC-engine air intake noise at earlystages. The urgent focus on the increasing CO2 emissions and the efficiency of IC-engines, aswell as new techniques such as homogeneous charge compression ignition (HCCI) mightworsen the noise situation. LÄS MER

  3. 2. IC-engine intake noise predictions based on linear acoustics

    Författare :Magnus Knutsson; Mats Åbom; Antonio Torregrosa; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik;

    Sammanfattning : Shorter product development cycles, densely packed engine compartments and intensified noise legislation increase the need for accurate predictions of IC-engine air intake noise at early stages. The urgent focus on the increasing CO2 emissions and the efficiency of IC-engines, as well as new techniques such as homogeneous charge compression ignition (HCCI) might worsen the noise situation. LÄS MER

  4. 3. Acoustic modeling and testing of exhaust and intake system components

    Författare :Yasser El Nemr; Hans Bodén; Antonio Torregrosa; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Intake and exhaust orifice noise contributes to interior and exterior vehicle noise. The order noise radiated from the orifice of the intake and exhaust systems is caused by the pressure pulses generated by the periodic charging and discharging process and propagates to the open ends of the duct systems. LÄS MER

  5. 4. Environmental factors in cardiovascular disease

    Författare :Mats Rosenlund; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Myocardial infarction; case-control study; aircraft noise; environmental tobacco smoke; ETS; drinking water; hardness; magnesium; calcium; air pollution; long-term; geographical information system; GIS;

    Sammanfattning : Cardiovascular disease is the main cause of death in Sweden and other developed countries. The purpose of this thesis is to assess the role of certain environmental factors in the etiology of cardiovascular disease, expressed as hypertension and myocardial infarction, focusing on aircraft noise, environmental tobacco smoke, drinking water hardness, and ambient air pollution. LÄS MER

  7. 5. Numerical Investigations of Generation and Propagation of Sound Waves in Low Mach Number Internal Flows

    Författare :Axel Kierkegaard; Gunilla Efraimsson; Mats Åbom; Wolfgang Polifke; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik;

    Sammanfattning : Traffic is a major source of environmental noise in modern day society. Subsequently, development of new vehicles are subject to heavy governmental legislations. The major noise sources on common road vehicles are engine noise, transmission noise, tire noise and, at high speeds, wind noise. LÄS MER