Abstract:In view of the unsatisfactory calculation accuracy of common turbulence models, two improved models, called improved low-Reynolds number (ILRN) k− ε and Detached EddySimulation (DES)-ILRN are proposed. Basing on the low-Reynolds number (LRN k− ε) turbulence model in this paper, revised concepts include the introduction of turbulence time scale, eddy viscosity coefficient limitation concept and separation perception model. Otherwise, the DES model is improved by introducing the ILRN model. The accuracy of the t… Show more
“…This model is a deep cavity model which is commonly used to investigate the feedback mechanism and control schemes for wind buffeting noise reduction. 8,30 Figure 1.Computational domain.…”
Section: Methodsmentioning
confidence: 99%
“…This model is a deep cavity model which is commonly used to investigate the feedback mechanism and control schemes for wind buffeting noise reduction. 8,30 The wind tunnel inlet was set as a speed inlet of 25 m/s, the outlet was a pressure outlet of 0 Pa. The top, left, and right sides of the wind tunnel were set as symmetrical boundary conditions.…”
Section: Geometry Model and Boundary Conditionsmentioning
The aim of this study is to investigate the effectiveness and mechanism of wind buffeting noise suppression using a new bionic structure inspired by the quiet flight of owls. Firstly, the new bionic schemes based on NACA0012 wing with two sinusoidal leading-edge serrations and one straight leading-edge curve are used in a cavity after verifying the simulation. Then, the results of the three bionic schemes are compared and analyzed. It is found that the schemes with leading-edge serrations and surface ridges can suppress wind buffeting noise effectively. In particular, the sinusoidal scheme with a wavelength λ = 0.24 c (chord length c) can significantly reduce resonance energies above 21 dB over a wide range of speeds. Furthermore, the study reveals that in the bionic scheme, only the negative pressure core moves in the opening and hits the trailing edge, which reduces the pressure fluctuation in the cavity. The boundary layer thickness (BLT) also fluctuates in span under the influence of the leading-edge serration and the surface ridge, which is favorable for suppressing wind buffeting noise. However, the suppression effect is not solely related to the fluctuation of BLT in the span at the trailing edge but is also influenced by the minimum BLT at this point. Therefore, if the BLT has a certain intensity fluctuation in the span, and the minimum BLT at the trailing edge is close to that of the smooth airfoil scheme, the noise suppression effect is significant.
“…This model is a deep cavity model which is commonly used to investigate the feedback mechanism and control schemes for wind buffeting noise reduction. 8,30 Figure 1.Computational domain.…”
Section: Methodsmentioning
confidence: 99%
“…This model is a deep cavity model which is commonly used to investigate the feedback mechanism and control schemes for wind buffeting noise reduction. 8,30 The wind tunnel inlet was set as a speed inlet of 25 m/s, the outlet was a pressure outlet of 0 Pa. The top, left, and right sides of the wind tunnel were set as symmetrical boundary conditions.…”
Section: Geometry Model and Boundary Conditionsmentioning
The aim of this study is to investigate the effectiveness and mechanism of wind buffeting noise suppression using a new bionic structure inspired by the quiet flight of owls. Firstly, the new bionic schemes based on NACA0012 wing with two sinusoidal leading-edge serrations and one straight leading-edge curve are used in a cavity after verifying the simulation. Then, the results of the three bionic schemes are compared and analyzed. It is found that the schemes with leading-edge serrations and surface ridges can suppress wind buffeting noise effectively. In particular, the sinusoidal scheme with a wavelength λ = 0.24 c (chord length c) can significantly reduce resonance energies above 21 dB over a wide range of speeds. Furthermore, the study reveals that in the bionic scheme, only the negative pressure core moves in the opening and hits the trailing edge, which reduces the pressure fluctuation in the cavity. The boundary layer thickness (BLT) also fluctuates in span under the influence of the leading-edge serration and the surface ridge, which is favorable for suppressing wind buffeting noise. However, the suppression effect is not solely related to the fluctuation of BLT in the span at the trailing edge but is also influenced by the minimum BLT at this point. Therefore, if the BLT has a certain intensity fluctuation in the span, and the minimum BLT at the trailing edge is close to that of the smooth airfoil scheme, the noise suppression effect is significant.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
