scholarly journals Numerical simulation on near-field aerodynamic noise of an adjustable-blade axial-flow fan

AIP Advances ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 095116
Author(s):  
Lin Wang ◽  
Nini Wang ◽  
Chunguo An ◽  
Suoying He ◽  
Ming Gao
Keyword(s):  
Numerical Simulation ◽  
Near Field ◽  
Axial Flow ◽  
Aerodynamic Noise ◽  
Axial Flow Fan

scholarly journals Numerical simulation and experimental research on the aerodynamic performance of large marine axial flow fan with a perforated blade

2017 ◽  
Vol 37 (3) ◽  
pp. 410-421 ◽  
Author(s):  
Xinglin Yang ◽  
Chenhui Wu ◽  
Huabing Wen ◽  
Linglong Zhang
Keyword(s):  
Numerical Simulation ◽  
Noise Reduction ◽  
Axial Flow ◽  
Internal Flow ◽  
Experimental Tests ◽  
Aerodynamic Noise ◽  
Surface Boundary ◽  
Axial Flow Fan ◽  
Suction Surface ◽  
Noise Characteristics

In this study, some of the optimal parameters for a new-style marine axial flow fan are defined by using numerical simulation and experimental tests with a large marine axial flow fan, based on the analysis of the blade perforation’s influences on its internal flow field and aerodynamic noise characteristics. Test result shows that the noise reduction for the axial flow fan with perforated blade is about 3 dB when the blade perforation diameter D is 10 mm and its deflection angle α is 45°. The results of the study show that there is an inhibitory effect on the discrete noise of axial flow fan with perforated blade on the tip area, and its total noise level emerged as the fluctuated distribution characteristics with the increase in the perforation diameter D and reduced along with the increase in the deflection of perforation angle α, at the same time varied as a linear characteristics, which can be reasonably explained by the acoustic interference theory. The results of the study have also further confirmed that the improvement of the flow of axial flow fan with perforated blade helps to reduce the pressure pulsation amplitude caused by the turbulence of the blade surface boundary layer, thereby suppressing the back-flow and vortex from the pressure surface to the suction surface efficiently. It is indicated that the improved vortex shedding phenomenon at the blade trailing edge after perforation on the area of blade tip is the main reason for the aerodynamic noise reduction of axial flow fan.

scholarly journals The influence of axial-flow fan trailing edge structure on internal flow

2018 ◽  
Vol 10 (11) ◽  
pp. 168781401881174
Author(s):  
Weijie Zhang ◽  
Jianping Yuan ◽  
Banglun Zhou ◽  
Hao Li ◽  
Ye Yuan
Keyword(s):  
Numerical Simulation ◽  
Low Frequency ◽  
Axial Flow ◽  
Internal Flow ◽  
Axial Flow Fan ◽  
Trailing Edge ◽  
Edge Structure ◽  
Blade Loading ◽  
Wideband Noise ◽  
Fluctuation Amplitude

Axial-flow fan with advantages such as large air volume, high head pressure, and low noise is commonly used in the work of air-conditioner outdoor unit. In order to investigate the internal flow mechanism of the axial-flow fan with different trailing edge structures of impellers, four kinds of impellers were designed, and numerical simulation and experiment were deployed in this article. The pressure distribution on the blades surface and distribution of vorticity in impellers were obtained using numerical simulation. Distribution of blade loading and velocity at the circumference are discussed. The relationship between the wideband noise and the trailing edge was established based on the experiment results. The results show that after the optimization of the trailing edge structure, the distribution of vorticity near the trailing edge of the blade is more uniform, especially at the trailing edge of 80% of the chord length of the suction surface. From the blade height position of 70% to the impeller tip, the pressure on the surface rapidly increases due to the tip vortex and the vortex shedding on the blade edge occurred in the top region of impeller. The pressure fluctuation amplitude at the trailing edge structure of the tail-edge optimization structure is smaller. In the distribution of blade loading, the three tail-edge optimization structures have smaller pressure fluctuations and pressure differences at the trailing edge structure. It is extremely important to control the fluctuation amplitude at the trailing edge. The amplitude of low-frequency sound pressure level of optimizing the trailing edge structure decreases obviously in the range of 50–125 Hz, and the optimization structure of trailing edge has an obvious effect on low-frequency wideband noise.

213 Relation between Aerodynamic Noise and Velocity Fluctuation around Rotor Blade of Axial Flow Fan

2012 ◽  
Vol 2012.65 (0) ◽  
pp. 67-68
Author(s):  
Masatomo Shiotuki ◽  
Taro Nakamura ◽  
Hiromitsu Hamakawa ◽  
Eru Kurihara
Keyword(s):  
Velocity Fluctuation ◽  
Rotor Blade ◽  
Axial Flow ◽  
Aerodynamic Noise ◽  
Axial Flow Fan

Relationship between Aerodynamic Noise and Velocity Fluctuation in the Near-wake of Rotor Blade of Axial Flow Fan

2016 ◽  
Vol 2016.26 (0) ◽  
pp. 110
Author(s):  
Hiromitsu HAMAKAWA ◽  
Yuta YAMAUCHI ◽  
Kaisei ODA ◽  
Eru KURIHARA ◽  
Hidechito HAYASHI
Keyword(s):  
Velocity Fluctuation ◽  
Rotor Blade ◽  
Axial Flow ◽  
Aerodynamic Noise ◽  
Axial Flow Fan ◽  
Near Wake

scholarly journals Correlation between Aerodynamic Noise and Velocity Fluctuation of Tip Leakage Flow of Axial Flow Fan

2012 ◽  
Vol 02 (04) ◽  
pp. 228-234
Author(s):  
Hiromitsu Hamakawa ◽  
Masatomo Shiotsuki ◽  
Takaaki Adachi ◽  
Eru Kurihara
Keyword(s):  
Velocity Fluctuation ◽  
Axial Flow ◽  
Aerodynamic Noise ◽  
Leakage Flow ◽  
Tip Leakage Flow ◽  
Axial Flow Fan ◽  
Tip Leakage

scholarly journals Influence of Chord Lengths of Splitter Blades on Performance of Small Axial Flow Fan

2015 ◽  
Vol 9 (1) ◽  
pp. 361-370
Author(s):  
Guoqi Li ◽  
Lifu Zhu ◽  
Yongjun Hu ◽  
Yingzi Jin ◽  
Toshiaki Setoguchi ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Axial Flow ◽  
Internal Flow ◽  
Leading Edge ◽  
Chord Length ◽  
Aerodynamic Noise ◽  
Axial Fan ◽  
Axial Flow Fan ◽  
Suction Surface ◽  
Small Axial Flow Fan

On the basis of small axial fan with five blades, 6 types of small axial flow fans with different chord lengths splitter blades were designed. Numerical simulation of 6 fan models with splitter blades and prototype fan were done by using Fluent. Based on the obtained simulation results, internal flow characteristics and aerodynamic noise were analyzed and compared. It indicates that: splitter blades with suitable chord length have improved significantly on internal flow characteristics, which inhibits backflow from pressure surface to the suction surface at blade tip and leading edge and restrains flow separation. The 6 model fans are better than prototype fan on aerodynamic noise improvement, but too long or too short chord lengths are both disadvantage to improve aerodynamic noise. The results reveal that 2/6, 3/6 and 4/6 chord length model have relatively better acoustic characteristics and internal flow characteristics. The research program will offer a reference for structural improvements and noise reduction on small axial flow fan.

Sign in / Sign up

Export Citation Format

Share Document