Prediction of Vibro-Acoustic Response of Enclosed Spaces by Using Structural Modification Techniques

Date

2010-09-22

Author

Demirkan, O.
BAŞDOĞAN, FATMA İPEK
Özgüven, Hasan Nevzat
Çalışkan, Mehmet

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

104
views

0
downloads

Low frequency noise caused by vibrating panels can become a problem for vehicles from NVH standpoint. The vibro-acoustic analysis of a simplified vehicle model is presented in this study. Analysis of vibro-acoustic behavior includes frequency response analysis of structure by Finite Element Method (FEM) and sound pressure level (SPL) prediction of the cabin interior by Boundary Element Method (BEM). The structural design of the vibrating panels can be modified by adding stiffeners to improve the acoustic field inside the cabin. The dynamic analysis of the structural model must be repeated after every modification which will be a time consuming process in the design stage. In this study, a methodology that utilizes the frequency response functions (FRFs) of the original model for the reanalysis of the structure that is subjected to structural modification is adapted. Modal analysis of the original structure is performed only once to obtain the receptance values. Then, the structural modification method is used to calculate the receptances of the modified system. The structural modification method uses the receptances of the original system and the dynamic stiffness matrix of the modifying part of the structure. The response of the structure obtained from receptances of the modified structure is then used to supply vibration data as boundary condition for acoustic analysis of the cavity for SPL prediction at desired points.

Subject Keywords

Frequency

URI

https://hdl.handle.net/11511/53803

Collections

Department of Mechanical Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

The effects of structural modifications on acoustic characteristics of enclosed bodies Demirkan, Özlem; Özgüven, Hasan Nevzat; Çalışkan, Mehmet; Department of Mechanical Engineering (2010) Low frequency noise caused by vibrating panels can pose problems for vehicles from noise, vibration and harshness (NVH) standpoint. In order to reduce interior noise levels in cars, some structural modifications are required on the car body. Structural modifications studied in this work are stiffeners welded on the walls of enclosed structure to change vibration characteristics. In this thesis, interaction between acoustic domain inside closed structures and their vibrating enclosing boundaries are analyzed...
Modeling of helically applied current to the inductively coupled radio frequency plasma torch in two dimensions Cantürk, Mehmet; Bilikmen, Kadri Sinan; Department of Physics (2004) The electrodeless plasma discharge is typically driven by radio frequency (RF) power supply within the range (0.2 Ł 40 MHz). The applied power is coupled into the plasma inductively called inductively coupled plasma (ICP). RF ICP technique has achieved significance importance in a diversity of research and industrial applications for over the last threes decades. It is still required to undertake both theoretical and experimental research. In this work, RF ICP technique is applied on the torch modeling in 2...
Optimization of Frequency Lowering Algorithms for Getting the Highest Speech Intelligibility Improvement by Hearing Loss Simulation ARIÖZ, UMUT; Günel Kılıç, Banu (2015-06-01) High frequency hearing loss is a growing problem for both children and adults. To overcome this impairment, different frequency lowering methods (FLMs) were tried from 1930s, however no satisfaction was provided up to now. In this study, for getting higher speech intelligibility, eight combinations of FLMs which were designed originally were tried with simulated sounds onto normal hearing subjects. These improvements were calculated by the difference with standard hearing aid method, amplification. High fre...
Prediction of sound transmission characteristics of multiple elastomeric bulb seals Barutçu, Burak Nebil; Çalışkan, Mehmet; Department of Mechanical Engineering (2017) Prevention of transmitted sound through car doors is a critical issue; as doors are the weakest parts of a car assembly in terms of sound isolation performance. Main path for sound transmission is through the seals between the car body and the door. Hence, the examination of sound transmission loss characteristics of seals between the car body and door is important to improve the sound isolation characteristics of the door assembly. The aim of this research is prediction of the sound transmission characteri...
Prospects of FMCW-based frequency diverse array radar Cetiner, Ramazan; Cetintepe, Cagri; Demir, Şimşek; Hizal, Altunkan (2019-11-01) The linear frequency modulated (LFM) frequency modulated continuous wave (FMCW)-based frequency diverse array (FDA) radar concept is investigated in detail. The radar operates as a linear pulsed FMCW/FDA in the transmission (TX) mode while it operates as a pulsed FMCW/phased array (PA) in the receiving mode. The issues such as low signal-to-noise ratio (SNR) of FDA, the time-angle scanning and time-range ambiguities are studied. It is shown that the local instantaneous frequency bandwidth is much smaller th...

Citation Formats

O. Demirkan, F. İ. BAŞDOĞAN, H. N. Özgüven, and M. Çalışkan, “Prediction of Vibro-Acoustic Response of Enclosed Spaces by Using Structural Modification Techniques,” 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53803.