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 The exciting sources for axial vibration of disk,especially the new axial gas dynamic force induced by travelling waves and its properties,and influence on the vibration of disks are studied.It is shown that the travelling wave induces new gasdynamic force which can damp out the foreward traveling wave vibration and induces the self exciting vibration for the backward travelling wave vibration.Because... The exciting sources for axial vibration of disk,especially the new axial gas dynamic force induced by travelling waves and its properties,and influence on the vibration of disks are studied.It is shown that the travelling wave induces new gasdynamic force which can damp out the foreward traveling wave vibration and induces the self exciting vibration for the backward travelling wave vibration.Because it is unavoidable that various distributed stationary forces act on the disk,the resonance in company with the self exciting stationary wave vibrations is excited during the critical speeds of disk.The resonance,in essentials the self exciting vibration,is the reason for dangerous stationary wave vibration.This is a new conception.The equation for calculating the instabitity of the stationary wave vibration of the disk is also given in the paper.  本文对涡轮机中轴流叶轮盘的激振源 ,特别是行波振动诱发的轴向力、力的性质、对振动的影响等作了分析。指出行波振动会诱发轴向力 ,此力对压气机和涡轮盘的前行波振动起阻尼作用 ,而对后行波则是自激力。涡轮机中轮盘上经常受到沿圆周分布不均的不变力作用 ,激起驻波振动 ,振动诱发的轴向力又激起盘的自激振动 ,如无足够阻尼则导致失稳 ,造成轮盘破裂事故。不仅是共振 ,尤其是自激振动失稳是本文提出轮盘驻波振动非常危险的原因  As the travelling wave vibration of bevel gears caused a number of aircraft accidents, its vibrational behaviour has been studied theoretically and experimentally by Xu et al [1] and Han et al [2]. But, no papers have been found concerning the travelling wave vibration of duplex helical gears. The three contributions of this paper will be first stated and then given concise explanation in the next three paragraphs. The authors, for the first time, succeed in performing simulation calculations of... As the travelling wave vibration of bevel gears caused a number of aircraft accidents, its vibrational behaviour has been studied theoretically and experimentally by Xu et al [1] and Han et al [2]. But, no papers have been found concerning the travelling wave vibration of duplex helical gears. The three contributions of this paper will be first stated and then given concise explanation in the next three paragraphs. The authors, for the first time, succeed in performing simulation calculations of dynamic responses of the travelling wave vibration of duplex helical gears in a star transmission. Gear system vibration and gear structure vibration occur simultaneously, but past theoretical research studies them separately. Different from past research, we do not separate them in our theoretical study but analyze such vibrations just as they actually occur. By analyzing the system of star transmission, we obtain the dynamic loads acting on the duplex helical gears. With the dynamic loads known, we employ threedimensional finite element method to obtain the responses of forward and backward travelling wave vibrations of the first three nodal diameters of duplex helical gears. The authors discover that difference of meshing frequencies of duplex helical gears affects greatly dynamic responses of travelling wave vibration. Two different meshing frequencies may excite two different resonant vibration modes of gear structure and thus cause coupled vibration. Certain values of parameters are selected by the authors to make an analytical study. For rotational speed n=18839.5 rpm of input shaft, we obtain calculated results. When there is only dynamic load acting on star gear No.2, the backward travelling wave vibration of the third nodal diameter is excited and the calculated curve is shown in Fig.8(b). When the duplex gears are in meshing, coupled vibration occurs. Coupled vibration is the result of coupling of two vibrations: backward travelling wave vibration of the third nodal diameter excited by star gear No.2 and torsional vibration excited by star gear No.3. The calculated curve of coupled vibration is shown in Fig.8(a). It can be seen from Figs.8(a) and 8(b) that coupling makes dynamic response increase by nearly 100%. This theoretical result is helpful for explaining the appearance of the phenomenon of big resonant vibration during experimenting on test bed. The authors also discover that dynamic stresses of travelling wave vibration of duplex gears do not necessarily decrease with increasing number of nodal diameters. This is because in the case of duplex helical gears, there exist two different meshing frequencies. It is well known that the dynamic stresses of travelling wave vibration of a pair of gears always decrease with increasing number of nodal diameters. All computations of this paper are completed on a microcomputer.  本文用三维有限元方法研究了星型传动中双联斜齿圆柱齿轮结构的行波共振。根据星型传动系统计算出的作用在双联斜齿轮上的动态载荷,成功地模拟计算出了双联齿轮处于一、二和三节径前、后行波共振时的动态响应,其响应分布形态与理论分析和实验响应曲线吻合较好。数值计算结果表明,在双联齿轮传动中,由于两齿轮啮合频率的不同,将会对齿轮结构的行波共振响应产生很大影响。这一点在设计具有双联齿轮传动的系统结构时应特别值得注意。本文通过实例计算进行了比较详细的讨论。  transfer matrix method for the travelling wave vibration and transient response analysis of a rotating lightweight gear is presented.A lightweight gear is modeled by a series of truncated conical shells.From the theory of the shells and plates,the transfer matrix formulas of a truncated conical shell are derived in which the effect of centrifugal force and Coriolis force are included.At the end of the paper,two examples,a rotating semispherical shell and a lightweight gear,are presented and the results... transfer matrix method for the travelling wave vibration and transient response analysis of a rotating lightweight gear is presented.A lightweight gear is modeled by a series of truncated conical shells.From the theory of the shells and plates,the transfer matrix formulas of a truncated conical shell are derived in which the effect of centrifugal force and Coriolis force are included.At the end of the paper,two examples,a rotating semispherical shell and a lightweight gear,are presented and the results are compared with those of experiment and those reported by other investigators utilizing various analytical technigues. The examples show that the accuracy of the method is satisfactory.  本文用截锥壳模拟薄辐齿轮，由截锥薄壳理论导出了计算转动态截锥壳振动特性及瞬态响应的传递矩阵公式。文末给出了算例。  
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