排序方式: 共有27条查询结果,搜索用时 201 毫秒
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发动机叶片扭转和弯曲变形同步测量新方法 总被引:1,自引:0,他引:1
扭转和弯曲变形测量可以确定叶片弯扭变形耦合的特征,为叶片弯扭耦合分析提供可用的试验手段。本文提出了一种发动机叶片扭转和弯曲变形同步测量的新方法,其中,扭转角度测量方法能更加灵活地应用于测量叶片类形状不规则构件的扭转变形,而弯曲变形测量方法解决了叶片变形方向未知且存在弯扭耦合时的叶片变形测量问题,从而可实现对叶片截面扭转和弯曲变形的同步测量。对上述测量方法进行了专门的验证试验,结果表明:与传统方法测量结果相比,扭转角度测量偏差小于1%,挠度测量偏差小于2%,满足工程测量精度要求。 相似文献
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The growth of GaP layer on GaN with and without buffer layers by metal-organic chemical vapour deposition (MOCVD) has been studied. Results indicate that the GaP low temperature buffer layer can provide a high density of nucleation sites for high temperature (HT) GaP growth. These sites can promote the two-dimensional (2D) growth of HT GaP and reduce the surface roughness. A GaP single crystal layer grown at 680°C is obtained using a 40-nm thick GaP buffer layer. The full-width at half-maximum (FWHM) of the (111) plane of GaP layer, measured by DCXRD, is 560 arcsec. The GaP layer grown on GaN without low temperature GaP buffer layer shows a rougher surface. However, the FWHM of the (111) plane is 408 arcsec, which is the indication of better crystal quality for the GaP layer grown on GaN without a low temperature buffer layer. Because it provides less nucleation sites grown at high growth temperature, the three-dimensional (3D) growth is prolonged. The crystalline quality of GaP is lightly improved when the surface of GaN substrate is pretreated by PH3 , while it turned to be polycrystalline when the substrate is pretreated by TEGa. 相似文献
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碟形弹簧特性曲线非线性有限元计算 总被引:5,自引:0,他引:5
本文利用有限单元法,在改进加载方法的前提下,详细计算了多种碟形弹簧的非线性特性曲线,得到了与精确解和实验值符合得非常好的精度很高的结果. 相似文献
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A nucleon-nucleus dynamics model was developed to investigate the proton-,neutron-,and deuteron-induced reactions at hundreds of MeV/nucleon.In this model,the trajectory of incident nucleon is described by classical mechanics,and the probability of reaction between the nucleon and nucleus is calculated by exponential damping.It is shown that the total reaction cross sections calculated by the model agree in general with the predictions by the CDCC and the experimental data.The model was applied to investigate the nucleon stripping in deuteron-induced reactions and its symmetry energy dependence. 相似文献
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The stochastic stability of a logistic model subjected to the effect of a random natural environment, modeled as Poisson white noise process, is investigated. The properties of the stochastic response are discussed for calculating the Lyapunov exponent, which had proven to be the most useful diagnostic tool for the stability of dynamical systems. The generalised It? differentiation formula is used to analyse the stochastic stability of the response. The results indicate that the stability of the response is related to the intensity and amplitude distribution of the environment noise and the growth rate of the species. 相似文献