GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Li, Kai Ming  (4)
  • Comparative Studies. Non-European Languages/Literatures  (4)
Material
Publisher
Person/Organisation
Language
Years
FID
Subjects(RVK)
  • Comparative Studies. Non-European Languages/Literatures  (4)
RVK
  • 1
    Online Resource
    Online Resource
    On the acoustic performance of hybrid mufflers.
    Acoustical Society of America (ASA) ; 2011
    In:  The Journal of the Acoustical Society of America Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2484-2484
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2484-2484
    Abstract: The acoustic attenuation of hybrid mufflers including perforated screens and sound-absorbent materials is investigated in the current study. An analytical method based on a 2-D mode matching technique is used to model an axisymmetrical hybrid muffler. In the theoretical analysis, the hybrid muffler is divided into a number of sections in different homogeneous media with different acoustical characteristics. The acoustic properties of sound absorbent materials and perforated screens are taken into account to obtain eigenfunctions for wave propagation through the air and sound absorbent materials. A system of equations can be solved by matching the acoustic pressure and axial velocity across different sections, which leads to the solution for the determination of the muffler’s transmission loss (TL). The numerical predictions of TL show good agreements with published experimental data. The developed analytical approach is then used to examine the effect of the inner structure of the hybrid mufflers on their acoustic performance. Finally, a hybrid muffler with mixed absorbent materials is investigated. The predicted results show that the hybrid muffler with full packed housing can lead to an improved acoustic attenuation at broad band frequencies. [Work sponsored by the China Scholarship Council.]
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.3588181
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2011
    detail.hit.zdb_id: 1461063-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Prediction of flow induced noise near a rigid body at low Mach numbers.
    Acoustical Society of America (ASA) ; 2011
    In:  The Journal of the Acoustical Society of America Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2522-2522
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2522-2522
    Abstract: For low Mach number flow around a solid body, the far-field sound pressure is dominated by dipole sources comparing with the monopole and quadruple components. The dipole sources are created by the unsteady surface pressure distributions due to the presence of a turbulent boundary layer in the vicinity of the solid body. The far-field sound pressure can be calculated by integrating the time derivative of the wall-pressure fluctuations at the surface of the rigid body. Recent development in computational fluid dynamics (CFD) brings a powerful tool for predicting unsteady turbulent flow fields and the generation mechanism of aerodynamic noise. The current study investigates the use of improved CFD method to accurately simulate the flow fields near a solid body. The information of the flow field is then used to calculate the far field sound pressures. Extensive computations have been conducted to calculate the noise induced by the flow over a circular cylinder and an automobile’s rear view mirror. The calculated sound pressure levels have shown to agree well with published experimental results. [Work sponsored by the China Scholarship Council.]
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.3588347
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2011
    detail.hit.zdb_id: 1461063-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Experimental and computational studies of vortex shedding and aerodynamic sound for flow over a square cylinder near a rigid wall.
    Acoustical Society of America (ASA) ; 2011
    In:  The Journal of the Acoustical Society of America Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2386-2386
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 129, No. 4_Supplement ( 2011-04-01), p. 2386-2386
    Abstract: Flow around a bluff body near a solid wall, such as a circular or rectangular cylinder placed in a uniform flow near a solid boundary, is of fundamental importance. The reduction in the aerodynamic sound is a very important issue, for example, flow induced noise in tall buildings, bridges, high-speed trains, windmills, and computer cooling fans. This type of problem has been addressed extensively both experimentally and theoretically in the past. The flow past a long rectangular cylinder is usually associated with vortex shedding, which can be affected strongly by the presence of a nearby wall. Flow past a solid body induces vortices and the vortex acceleration will cause sound. In the present study, the aerodynamic sound generated by flow past a rectangular cylinder of various configurations was investigated experimentally in a low-speed quiet wind tunnel. A numerical study using large scale eddy Simulation technique has also been conducted to compute the sound generation due to vortex shedding. Experimental results are compared with the numerical predictions. [Work sponsored by the China Scholarship Council.]
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.3587742
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2011
    detail.hit.zdb_id: 1461063-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Propagation of wind turbine noise through the turbulent atmosphere
    Acoustical Society of America (ASA) ; 2014
    In:  The Journal of the Acoustical Society of America Vol. 136, No. 4_Supplement ( 2014-10-01), p. 2205-2205
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 136, No. 4_Supplement ( 2014-10-01), p. 2205-2205
    Abstract: It is well known that turbulence can cause fluctuations in the resulting sound fields. In the issue of wind turbine noise, such effect is non-negligible since either the inflow turbulence from nearby turbine wakes or the atmospheric turbulence generated by rotating turbine blades can increase the sound output of individual turbines. In this study, a combined approach of the Finite Element Method (FEM) and Parabolic Equation (PE) method is employed to predict the sound levels from a wind turbine. In the prediction procedure, the near field acoustic data is obtained by means of a computational fluid dynamic program which serves as a good starting field of sound propagation. It is then possible to advance wind turbine noise in range by using the FEM/PE marching algorithm. By incorporating the simulated turbulence profiles near wind turbine, more accurate predictions of sound field in realistic atmospheric conditions are obtained.
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.4899997
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2014
    detail.hit.zdb_id: 1461063-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...