Study on acoustic, vibration and flow induced noise characteristics of T-shaped pipe with a square cross-section

Mori, Masaaki; Masumoto, Takayuki; Ishihara, Kunihiko

doi:10.1016/j.apacoust.2017.01.022

Cited by 25 publications

(7 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The BEM solver in commercial acoustic simulation package, WAON, is used to solve the acoustic characteristics [30]. In a sound field that satisfies the threedimensional Helmholtz equation, the Kirchhoff-Helmholtz integral equation [31] for sound pressure is described as follows with respect to a point i and an area S of a surface on a boundary.…”

Section: Acoustic Simulationmentioning

confidence: 99%

Wake-Body Interaction Noise Simulated by the Coupling Method Using CFD and BEM

Mori¹

2020

Vortex Dynamics Theories and Applications

Self Cite

View full text Add to dashboard Cite

In many engineering applications, obstacles often appear in the wake of obstacles. Vortices shed from an upstream obstacle interact with downstream obstacle and generate noise, for example blades in a turbomachinery, tubes in a heat exchanger, rotating blades like a helicopter and wind turbine and so on. This phenomenon is called wake-body interaction or body-vortex interaction (BVI). The rod-airfoil and airfoil-airfoil configurations are typical models for the wake-body interaction. A rod and an airfoil are immersed upstream of the airfoil. In this chapter, we review the noise mechanism generated by the wake-body interaction and show the numerical results obtained by the coupling method using commercial CFD and acoustic BEM codes. The results show that depending on the spacing between the rod or airfoil and the airfoil, the flow patterns and noise radiation vary. With small spacing, the vortex shedding from the upstream obstacle is suppressed and it results in the suppression of the sound generation. With large spacing, the shear layer or the vortices shed from the upstream obstacle impinge on the downstream obstacle and it results in the large sound generation. The dominant peak frequency of the generated sound varies with increase in the spacing between the two obstacles.

show abstract

Section: Acoustic Simulationmentioning

confidence: 99%

Wake-Body Interaction Noise Simulated by the Coupling Method Using CFD and BEM

Mori¹

2020

Vortex Dynamics Theories and Applications

Self Cite

View full text Add to dashboard Cite

show abstract

“…Flow separation and vortex shedding generated from models cause strong pressure fluctuations, which is the main reason for flow-induced noise [23][24][25][26]. The control of flow-induced noise at high flow velocities has become a significant component of underwater vehicle noise [27,28].…”

Section: Introductionmentioning

confidence: 99%

Control effect of superhydrophobic grooves on flow-induced noise generated by flow around cylindrical shell at large Reynolds number

Niu,

Qin,

Liu

et al. 2023

Phys. Scr.

View full text Add to dashboard Cite

Flow-induced noise is an important factor affecting the quiet performance of underwater vehicles. Superhydrophobic surfaces are an emerging technology for underwater vehicles. In this study, a superhydrophobic surface is innovatively applied to the flow-induced noise control of underwater cylindrical shells. Alternating no-slip and no-shear surfaces are used to simulate the superhydrophobic surface with spanwise superhydrophobic grooves so that the flow regime and flow-induced noise of a no-slip cylinder are compared with the superhydrophobic cylinder under a high Reynolds number. The results show that the superhydrophobic surface can effectively delay flow separation and control the size of the wake shedding vortex. The flow-shedding vortices mainly affect the flow-induced noise in the lower frequency range, which is consistent with the vortex shedding frequency. The radiation characteristics of the flow-induced noise generated by the fluctuation pressure are mainly influenced by the eigenfrequency of the model in the range of 100 Hz–5000 Hz. Moreover, the superhydrophobic surface can effectively reduce the flow-induced noise and change its radiation directivity at both high and low frequencies by controlling vortex shedding and reducing the fluctuation pressure, respectively. The findings reported here shed new light on the flow-induced noise control of underwater vehicles.

show abstract

“…Han et al [11] researched the flow-induced noise of natural gas manifolds by adopting LES and FW-H methods and obtained the best section area ratio of distribution pipe to outlet pipes for reducing noise. Mori et al [12] studied flow-induced noise characteristics of T-shaped pipe with a square cross-section. The results showed that the aerodynamic sound pressure depends on the inlet velocity, while the flow velocity affects little on the directivity and frequency characteristics of the sound pressure.…”

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of 3D Flow Field and Flow-Induced Noise Characteristics in a T-Shaped Reducing Tee Junction

Lv¹,

Wang²,

Guo³

et al. 2023

Fluid Dynamics &Amp; Materials Processing

View full text Add to dashboard Cite

The so-called T-shaped reducing tees are typically used to divide, change and control (to a certain extent) the flow direction in pipe networks. In this study, the Ffowcs Williams-Hawkings (FW-H) equation and the Large Eddy Simulation (LES) methods are used to simulate the flow-induced noise related to T-shaped reducing tees under different inlet flow velocities and for different pipe diameter ratios. The results show that the maximum flow velocity, average flow velocity, and vorticity in the branch pipe increase gradually as the related diameter decreases. Strong vorticity and secondary flows are also observed in the branch pipe, and the associated violent pressure fluctuations are found to be the main sources of flow-induced noise. In particular, as the pipe diameter ratio decreases from 1 to 0.45, the Total Sound Pressure Level (TSPL) increases by 6.8, 6.26, and 7.43 dB for values of the inlet flow velocity of 1, 2, and 3 m/s, respectively. The distribution characteristics of the flow-induced noise in the frequency domain follow similar trends for different pipe diameter ratios.

show abstract

Study on acoustic, vibration and flow induced noise characteristics of T-shaped pipe with a square cross-section

Cited by 25 publications

References 9 publications

Wake-Body Interaction Noise Simulated by the Coupling Method Using CFD and BEM

Wake-Body Interaction Noise Simulated by the Coupling Method Using CFD and BEM

Control effect of superhydrophobic grooves on flow-induced noise generated by flow around cylindrical shell at large Reynolds number

Numerical Simulation of 3D Flow Field and Flow-Induced Noise Characteristics in a T-Shaped Reducing Tee Junction

Contact Info

Product

Resources

About