运载火箭起飞段发动机喷流经过导流槽、发射台产生的噪声载荷会对地面发射设备造成一定的破坏，由噪声引发的振动对于运载火箭自身也会造成严重影响。总声压级、声功率谱密度及空间相关系数3个参数可描述完整的噪声场，但空间相关系数关注很少。由于空间相关特性的差异，同一声压级不同性质的噪声场在结构上产生的振动响应不同。从噪声场空间相关的基础理论出发，给出了空间相关理论曲线，研究了混响室空间相关特性；以某型号运载火箭整流罩为研究对象，开展星箭系统级噪声试验，获取了运载火箭表面声场分布规律，并基于试验数据研究了空间相关归一化表征方法，对比分析了混响室和整流罩内声场特性，结果表明整流罩内声场与混响声场空间相关特性接近，为运载火箭载荷与环境设计提供输入，为整流罩及有效载荷噪声环境试验方案设计提供支持。

During lift-off phase of launch vehicle flight, the noise produced by the deflector tunnel and launch deck when the engine’s plume flow away may destroy the ground launching device. And the noise environment can excite the vibration of launch vehicle. The characteristics of the acoustic field highly depend on total sound pressure level, noise power spectrum density and spatial correlation coefficient. Among them the spatial correlation coefficient is less investigated. However, the acoustic fields with different spatial correlation coefficient, but the same sound pressure level can induce different structural vibration response. In this paper, based on the theory of spatial correlation characteristic of acoustic field, the theoretical curves of spatial correlation are obtained and the spatial correlation characteristic of reverberation chamber is studied. Acoustic test of satellite-rocket system level is developed applying a type of launch vehicle fairing and the regular dis

阐述传递路径分析原理及结构力识别的多种估计方法,重点阐明了逆矩阵法载荷识别的原理及其关键参数(奇异值阈值)的意义。通过应用实例介绍传递路径分析的具体步骤,对比不同奇异值阈值的载荷力识别结果,并经测试得到传递函数,同时分析关键转速下各路径对车内噪声的贡献量。结果表明,车内150 Hz噪声主要由后悬置Z向路径引起;贡献量过大由载荷过大导致,而不是激励路径放大引起的。

The principle of noise transfer path analysis and many force identification methods, in particular the principle of inverse matrix load identification and significance of its key parameters (singular values threshold value) are elaborated in this paper. Then we present the steps of transfer path analysis in details with application examples, and compare loading force identification results of different singular value threshold value, and obtain the transfer function through test, we also analyze the contribution of all the transfer paths to interior noise at critical speeds. The results show that the 150Hz interior noise is mainly generated by rear suspension Z-direction path;excessive contribution is caused by overloading, not by enlarged exciting path.

基于统计能量法,利用VA ONE软件对海洋平台典型舱室结构在分体空调室外机空气噪声作用下的舱室噪声进行预报。在保证结构尺寸与载荷大小的前提下,改变分体空调室外机出风口朝向、对比分析舱室噪声,得出分体空调室外机出风口朝向会对舱室噪声产生较大影响。该研究对船舶与海洋工程舱室噪声预报及设备布置方面具有一定的参考价值。

Based on the Statistical Energy Analysis, this paper predicts the cabin noise of the typical cabin structure of the offshore platform under the air noise effect of the split air-conditioning outdoor unit with VA ONE software. Under the premise of the given structure size and the magnitude of load, this paper changes the air outlet orientation of the split air-conditioning outdoor unit, compares and analyzes the cabin noise. It concludes that the air outlet orientation has a great influence on cabin noise, which provides the certain reference for the cabin noise prediction and the equipment layout in Naval Architecture and Marine Engineering.

为了降低新型传动摆线齿轮减速器的噪声,对关键部件进行优化设计,采用试验手段对摆线齿轮减速器噪声及模态进行测试。综合测试结果发现减速器箱体及内部件固有频率在中频区域分布比较密集。当摆线轮与针轮啮合频率达到500 Hz以上将产生较大噪声;而当载荷达到50%以上时三齿轮传动对噪声贡献开始突显出来。最后提出避开固有频率、优化箱体结构及改进传动部件设计等减振降噪的措施。

In order to reduce the noise of a new-type transmission gearbox with cycloid gears, optimization design of the key component parts was done. The noise and modals of the gearbox were tested. It was found that the intrinsic frequency of the gearbox’s shell and the internal component parts is concentrated in low and medium frequency range. The noise increases greatly when the meshing frequency of the cycloid gear and the pin wheel exceeds 500Hz. And the three-gear transmission has large contribution to the noise when the load reaches 50% of the rated load. Finally, some measures for vibration and noise reduction were proposed, such as avoiding from the intrinsic frequency, optimizing the structure and improving the design of transmission parts.

随着先进飞行器性能的提高,它们面临着日益严峻的热、噪声、机械载荷等,在这些复杂载荷的作用下,会引发非线性振动特性。特别是高超飞行器的气动加热引起的高温直接影响材料的选择并且显著地改变结构的设计实践,所形成的热梯度与内部热膨胀也会使结构产生热屈曲现象。考虑到热声载荷的影响,针对带有温度梯度的热载荷与随机声载荷作用下四边简支板振动特性进行了研究。通过各向同性矩形薄壁结构在热声载荷作用下的大挠度非线性控制方程,导出了四边简支板的模态频率以及温度梯度作用下的热屈曲温度差。采用有限元数值计算方法计算了热声载荷作用下简支板热屈曲前后的动态应力响应,并对应力的概率密度、功率谱密度、有效值进行了详细的统计分析。

With the improvement of the advanced aircraft performance,they are facing increasingly severe aerodynamic heating,noise,mechanical load and so on,under the action of those complex loads,the aircrafts reveal nonlinear vibration characteristics.The aerodynamic heating from supersonic flight induces elevated temperatures that affect material selection and significantly alter structural design practices. Thermal gradients and internal thermal expansion also introduce thermal buckling phenomenon.Here,considering the influence of thermo-acoustic loadings, vibration characteristics of a simply supported plate under thermal loadings with temperature gradient and random acoustic loadings were investigated.According to nonlinear large deflection governing equations for isotropic thin-walled structures undergoing thermo-acoustic loadings,the modal frequencies of the simply supported plate,and its thermal buckling temperature difference with temperature gradient were derived.The dynamic stress res