Fan Noise Source Diagnostic Test - Computation of Rotor Wake Turbulence Noise

Nallasamy, M.; Envia, Edmane; Thorp, Scott A.; Shabbir, Aamir

doi:10.2514/6.2002-2489

Cited by 10 publications

(5 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Some works have highlighted the effects of the geometrical parameters such as the vane sweep or blade and vane counts for rotor/stator interaction noise. The most detailed investigation is the "Fan Noise Source Diagnostic Test" reported by NASA [2][3][4][5]. It deals with a stator with 54 radial vanes, a low-count stator with 26 radial vanes, and a low-noise stator with 26 swept vanes.…”

mentioning

confidence: 99%

Experimental Validation of a Cascade Response Function for Fan Broadband Noise Predictions

Posson

Roger

2011

AIAA Journal

View full text Add to dashboard Cite

The present paper is aimed at assessing an analytical prediction model for the broadband noise produced by the impingement of turbulence on a cascade, using a dedicated experiment. The model is a strip-theory approach based on a previously published formulation of the unsteady blade loading for a rectilinear cascade. The experimental setup is made of a single stationary cascade of vanes mounted downstream of a turbulence grid in an annular duct, at the exit of an open-jet anechoic wind tunnel. The statistical parameters of the turbulence measured with hot-wire anemometry are used as input data in the model. The in-duct predicted downstream acoustic power is compared with the measured power obtained from the far-field acoustic pressure. Measured and predicted variations of the acoustic power with the number of vanes of the cascade and with the turbulence intensity are found to be in good agreement. It is concluded that the analytical approach succeeds in highlighting three-dimensional effects and is promising for further comparisons in more complex annular configurations. = squared norm of the duct eigenfunction E m; = microphone angle in the horizontal plane P containing the center of the exhaust section = turbulence integral length scale 0 = exponential correction factor of the turbulence spectrum 0 = fluid density = interblade phase angle uu ! = power spectral density of the streamwise velocity ww K; r = three-dimensional wave-number turbulence spectrum for the vane normal velocity component divided by u 2 rmŝ ' = sweep angle in the duct reference framê = stagger angle in the duct reference frame m;= eigenvalue of the mode m;

show abstract

mentioning

confidence: 99%

Experimental Validation of a Cascade Response Function for Fan Broadband Noise Predictions

Posson

Roger

2011

AIAA Journal

View full text Add to dashboard Cite

show abstract

“…Previous studies on aerodynamics noise were mainly conducted by RANS [2][3]. According to the improvement of computer performance, studies by large eddy simulation (LES) which directly solve vortices of grid-scale are increasing [4][5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Noise prediction of a box fan by RANS simulation

Kitamura

Nohmi

2022

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

The characteristics of aerodynamic performance and aerodynamic noise of a box fan were evaluated to investigate the industrial applicability of computational fluid dynamics (CFD) with Reynolds averaged numerical simulation (RANS) model for fan design. In the case of unsteady RANS, the characteristic of the static pressure rise for flow rates was in good agreement with the experimental results. Aerodynamic noise performance at the design flow rate and low flow rate is well predicted using acoustic/viscous splitting technique based on unsteady RANS with multiple reference frame (MRF). As a result, it was able to evaluate the overall sound characteristic of each fan design relatively. The results suggest that the acoustic/viscous splitting technique based on RANS with MRF simulation has potential as a useful design tool.

show abstract

“…Over the past decade, many studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] have been devoted to achieve these design goals. The time accurate turbulence simulation such as large eddy simulation (LES) [2][3][4][5][6][7][8][9][10][11] and unsteady Reynolds-averaged Navier-Stokes (URANS) method [1,[11][12][13][14][15][16][17][18][19][20] were used to compute the spacetime history of the three-dimensional flow field of the outdoor unit.…”

Section: Introduction *mentioning

confidence: 99%

“…The time accurate turbulence simulation such as large eddy simulation (LES) [2][3][4][5][6][7][8][9][10][11] and unsteady Reynolds-averaged Navier-Stokes (URANS) method [1,[11][12][13][14][15][16][17][18][19][20] were used to compute the spacetime history of the three-dimensional flow field of the outdoor unit. Then the generalized Lighthill equation and its extended forms, such as Ffowcs Williams-Hawkings (FW-H) equation, Curle equation, and Lowson formulation, were applied to predict the corresponding sound field of the unit.…”

Section: Introduction *mentioning

confidence: 99%

Influence of surrounding structures upon the aerodynamic and acoustic performance of the outdoor unit of a split air-conditioner

Wu¹,

Liu²,

Pan³

2014

Chin. J. Mech. Eng.

View full text Add to dashboard Cite

DC-inverter split air-conditioner is widely used in Chinese homes as a result of its high-efficiency and energy-saving. Recently, the researches on its outdoor unit have focused on the influence of surrounding structures upon the aerodynamic and acoustic performance, however they are only limited to the influence of a few parameters on the performance, and practical design of the unit requires more detailed parametric analysis. Three-dimensional computational fluid dynamics(CFD) and computational aerodynamic acoustics(CAA) simulation based on FLUENT solver is used to study the influence of surrounding structures upon the aforementioned properties of the unit. The flow rate and sound pressure level are predicted for different rotating speed, and agree well with the experimental results. The parametric influence of three main surrounding structures(i.e. the heat sink, the bell-mouth type shroud and the outlet grille) upon the aerodynamic performance of the unit is analyzed thoroughly. The results demonstrate that the tip vortex plays a major role in the flow fields near the blade tip and has a great effect on the flow field of the unit. The inlet ring's size and throat's depth of the bell-mouth type shroud, and the through-flow area and configuration of upwind and downwind sections of the outlet grille are the most important factors that affect the aerodynamic performance of the unit. Furthermore, two improved schemes against the existing prototype of the unit are developed, which both can significantly increase the flow rate more than 6 %(i.e. 100 m 3 ·h −1 ) at given rotating speeds. The inevitable increase of flow noise level when flow rate is increased and the advantage of keeping a lower rotating speed are also discussed. The presented work could be a useful guideline in designing the aerodynamic and acoustic performance of the split air-conditioner in engineering practice.

show abstract

Fan Noise Source Diagnostic Test - Computation of Rotor Wake Turbulence Noise

Cited by 10 publications

References 10 publications

Experimental Validation of a Cascade Response Function for Fan Broadband Noise Predictions

Experimental Validation of a Cascade Response Function for Fan Broadband Noise Predictions

Noise prediction of a box fan by RANS simulation

Influence of surrounding structures upon the aerodynamic and acoustic performance of the outdoor unit of a split air-conditioner

Contact Info

Product

Resources

About