Sökning: "Fan-Noise"

Visar resultat 1 - 5 av 9 avhandlingar innehållade ordet Fan-Noise.

  1. 1. Turbomachinery Aeroacoustic Calculations using a Time Domain Chorochronic Method

    Författare :Martin Olausson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rotor Stator interaction; Fan-Noise; Time lag; Chorochronic; Nonlinear; Computational Aeroacoustics;

    Sammanfattning : Noise regulations for aircrafts that fly over populated areas are continuously becoming stricter. This in combination with increasing computational capabilities has boosted interest in aeroacoustic computations in the aerospace industry. LÄS MER

  3. 2. Turbomachinery Aeroacoustic Calculations using Nonlinear Methods

    Författare :Martin Olausson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear; CFD; Time Spectral; CAA; Ffowcs-Williams Hawkings; Broadband; Time lag; Computational Aeroacoustics; Fan-Noise; Rotor-Stator interaction; Buffer layer; Oscillating sphere; Newton-GMRES; Computational Fluid Dynamics; Acoustic analogies; Sponge; Counter-Rotating Propfan; Harmonic Balance Technique; Tone; FWH; Chorochronic periodicity; Hybrid RANS LES;

    Sammanfattning : Noise regulations for aircraft that fly over populated areas are becoming continuously stricter. This in combination with increasing computational capabilities has boosted interest in aeroacoustic computations in the aerospace industry. LÄS MER

  4. 3. Experimental Studies on the Aeroacoustics of Low-Speed Axial Fans

    Författare :Michail Vourakis; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; low-speed axial fans; electric fans; experimental; laser Doppler anemometry; low-pressure axial fans; cooling fan; aeroacoustics; rotating ring;

    Sammanfattning : Low-speed axial fans are used in thermal management systems of internal combustion and electric vehicles. These systems are compact, cost-effective, all while addressing safety concerns. On the downside, fan operation leads to flow induced noise. LÄS MER

  5. 4. Linear Quadratic Gaussian Controllers for Feedforward Active Noise Control : Pushing Performance and Moving Towards Adaptive Control

    Författare :Annea Barkefors; Mikael Sternad; Anders Ahlén; Lars-Johan Brännmark; Bengt Carlsson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; active noise control; ANC; LQG; feedforward control; sound field control; Elektroteknik med inriktning mot reglerteknik; Electrical Engineering with specialization in Automatic Control;

    Sammanfattning : Active noise control is a research area focused on using destructive interference of sound fields to attenuate undesired noise. Methods for active noise control are best suited for low frequency noise, as the complexity of the problem grows rapidly with frequency. LÄS MER

  7. 5. Predicting flow-generated noise from HVAC components

    Författare :Oscar Kårekull; Mats Åbom; Gunilla Efraimsson; Joachim Golliard; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow noise; noise prediction; HVAC; flödesalstrat ljud; bullerprediktion; HVAC;

    Sammanfattning : More energy efficient fans, i.e. larger sizes running at lower speeds, in Heating Ventilation and Air Conditioning (HVAC) systems decrease the fan noise and increase the importance of flow generated noise in other system components, e.g. LÄS MER