科考设备斜滑道入水流致噪声的数值模拟与实验测试研究

Numerical simulation and experimental study on the noise generated by scientific research equipment entering water in an inclined slideway

为了研究科考设备斜滑道入水的噪声预报问题,本文设计了一种斜滑道装置,利用CFD软件对不同入水速度与投放角度进行投放噪声的数值模拟,选用分离涡模型(detached-eddy simulation,DES)和FW-H(Ffowcs Williams-Hawkings,FW-H)声类比模型开展入水物体噪声计算。在计算得到水动力噪声的时域脉动压力结果后,通过傅里叶变换得到频域的噪声分布。本文设计了相关实验对数值结果进行验证,并通过分析典型工况下的流场域以及噪声的时域及频域特性,进一步分析实验与数值系统误差的来源。结果表明,流致噪声占总噪声的主要部分,斜滑道与科考设备之间的相互耦合作用、滑道壁的流固耦合现象、传送过程中不可避免的机械噪声以及声辐射特性数值模拟模型的不完备性是系统性误差的来源。

In order to study the noise prediction of scientific research equipment entering water in an inclined slideway,a kind of inclined slideway delivery device is designed in this paper.The CFD software is used to carry out the numerical simulation of launching noise at different entry speeds and with different incident angles.The detached-eddy simulation(DES)model and Ffowcs Williams-Hawkings(FW-H)acoustic analogy model are selected to calculate the noise generated by the equipment entering water.After calculation on the time-domain pulsation pressure of hydrodynamic noise,the noise distribution in frequency domain is obtained by Fourier transform.In this paper,relevant experiments are designed to verify the numerical results.The sources of systematic errors of the experimental and numerical methods are further derived by analyzing the flow field under typical working conditions and the characteristics of noise in time domain and frequency domain.The results show that the flow-induced noise is the main part of noises.The coupling between the inclined slideway and scientific research equipment,the fluid-structure coupling phenomenon of the slideway wall,the inevitable mechanical noise during the transmission process and the incomplete numerical simulation model of acoustic radiation characteristics are the sources of systematic errors.