Computation of Fan Noise Radiation through A Realistic Engine Exhaust Geometry with Flow

2003 ◽  
Author(s):  
Xin Zhang ◽  
Xiaoxian Chen ◽  
Chris L. Morfey ◽  
Brian J. Tester
Keyword(s):  
Fan Noise ◽  
Engine Exhaust ◽  
Noise Radiation

Effect of inlet reflections on fan noise radiation

AIAA Journal ◽  
1996 ◽  
Vol 34 (9) ◽  
pp. 1771-1777 ◽  
Author(s):  
H. D. Meyer
Keyword(s):  
Fan Noise ◽  
Noise Radiation

scholarly journals Frequency-Domain Linearized Euler Model for Turbomachinery Noise Radiation Through Engine Exhaust

AIAA Journal ◽  
2010 ◽  
Vol 48 (4) ◽  
pp. 848-858 ◽  
Author(s):  
Andrea Iob ◽  
Renzo Arina ◽  
Claudia Schipani
Keyword(s):  
Frequency Domain ◽  
Engine Exhaust ◽  
Noise Radiation ◽  
Euler Model

Research on Noise Control of Wheel Loader and Frequency Spectrum Analysis

2013 ◽  
Vol 373-375 ◽  
pp. 732-736
Author(s):  
Qian Zhang ◽  
Fa Chao Jiang ◽  
Jing Jing Liu ◽  
Sen Nan Song
Keyword(s):  
Fan Noise ◽  
Engine Exhaust ◽  
Power Train ◽  
Wheel Loader ◽  
Main Frequency ◽  
Cooling Fan ◽  
Exhaust Noise ◽  
Noise Frequency ◽  
Test Points ◽  
Damping Materials

The tested wheel loader machinery noise was 110dB and driver position was 108dB, more than Chinese earth-moving machinery standard. Engine noise is the main noise, so thirty-five test points were arranged around the cab and engine to analyze and find the main noise points. The frequency spectrogram show that the main frequency band for the engine and exterior cab are 120Hz and 216Hz, and the interior cab noise was caused by the vibration of the power train passed through the frame result in resonance. Analyzed and calculated the main frequency concludes that the main noise resources are engine exhaust noise and cooling fan noise. To decrease the noise, proper damping materials were affixed to the engine hood and interior cab, the metal pieces were tightened and the cooling fan and shock absorber were replaced with new ones that match the main noise frequency.

Fan Casing Noise Radiation

1991 ◽  
Vol 113 (1) ◽  
pp. 37-42 ◽  
Author(s):  
G. H. Koopmann ◽  
W. Neise ◽  
K. A. Cunefare
Keyword(s):  
Sound Pressure ◽  
Noise Spectrum ◽  
Centrifugal Fan ◽  
Noise Sources ◽  
Fan Noise ◽  
Noise Radiation ◽  
Starting Point ◽  
Element Program ◽  
Inlet Box ◽  
Subharmonic Frequency

This paper presents a method for assessing the extent of casing noise radiation of a centrifugal fan relative to the aeroacoustic sources associated with the inlet box of the fan. Central to the method is a boundary element program which is used to compute the acoustic pressures on the surfaces of the fan casing in terms of its surface vibration which in this case was measured experimentally. Data from an earlier experiment was used as the starting point for this study. Available data included sound pressure measurements near and away from the inlet box of the fan and vibration measurements over the casing of the fan. Noise from the outlet duct of the fan was purposely highly attenuated. Computations of sound pressure, intensity, and power indicated that, at the blade passing frequency (300 Hz), the aerodynamic sources generated near the entrance plane of the inlet box of the fan dominate the noise spectrum in the field. On the other hand, at the first subharmonic frequency of the blade tone (150 Hz), the sound power generated from the inlet box and fan casing are within 3 dB of each other. Thus, for effective noise control at this frequency, it would be necessary to include both noise sources in the overall treatment.

scholarly journals Lifting Fan Noise Studies

1969 ◽  
Author(s):  
G. Krishnappa ◽  
G. G. Levy
Keyword(s):  
Experimental Investigation ◽  
Aerodynamic Characteristics ◽  
Broadband Noise ◽  
Fan Noise ◽  
Noise Radiation ◽  
Close Spacing ◽  
Blade Passing Frequency ◽  
Low Levels ◽  
High Level ◽  
Inflow Conditions

The paper reviews the results of an experimental investigation of noise radiated from a VTOL lifting fan inlet under static inflow conditions. The results are discussed in the light of recent theoretical and experimental conclusions on compressor noise radiation, combined with relevant data on the aerodynamic characteristics of the fan. The presence of high level discrete tones, up to four harmonics of the blade passing frequency superimposed over a broadband noise extending from 200 to 15,000 cps, is attributed to close spacing between rotor and stator blades, Low levels of broadband noise were observed to be caused by low levels of turbulence at the intake. Analysis of the limited results shows the variation of broadband noise as the sixth power of the velocity of the flow relative to the blade.

Sign in / Sign up

Export Citation Format

Share Document