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51.
论文论述了钢板弹簧在弯曲过程中的热校形消除回弹原理,即钢板弹簧在高温下的软化与短时应力松弛综合作用机制。对弯曲回弹热校形规律进行了定量理论分析和实验验证。导出的公式可用来定量估算其它弯曲工序热校形工艺参数。采用的理论分析方法,可应用于其它种类钣金件热校形规律的研究中。 相似文献
52.
The analyses of finite deformation and stress for a hyperelastic rectangular plate with some voids under an uniaxial extension were conducted. The governing differential equations were given from the incompressibility condition of the material. The solution was approximately obtained from the minimum potential energy principle. The growth of voids was discussed. One can see that an initial central circular-cylinder void becomes an elliptic-cylinder void, but an initial non-centeral circular-cylinder void becomes an elliptic-like cylinder void and the center of void has a shift. The stress distributions along the edges of voids were given and the phenomenon of stress concentration was observed. The influences of the distribution manner and size of voids, as well as the distance between them on the growth of voids were analyzed. 相似文献
53.
INTRODUCTIONThemotionoftheflowinarotatingcurvedpipeisafundamentalproblem ,whosesolutionhaspotentialapplicationsingasturbines ,elec tricgenerators ,electricmotorsandsomeequip mentsusedinseparationprocesses.Itisimpor tanttoknowtheflowstructurecharacteristic… 相似文献
54.
微光夜视技术经过了几十年的发展,现在已经进入了实用阶段。研发微光夜视仪在军事和民用二方面都能发挥较大作用。文中回顾了微光夜视技术发展的历史和现状,并对发展趋势进行了展望。比较了各种技术的优势和劣势,分析了各国在军事方面的应用情况,提出了研究的必要性和可实现性。 相似文献
55.
利用电子表格Excel进行二元理想体系精馏过程中的逐板计算,可以快速且准确地得到理论塔板数、加料板位置及每一块理论塔板上的汽液组成. 相似文献
56.
LUO Xiaoyang Pascal PERROTIN YAN Quansheng 《天津大学学报(英文版)》2006,12(B09):117-121
A new concept of structurally dissipating rock-shed (SDR) was developed by the lab of Tonello IC and LOCIE-ESIGEC ( France). To decide the dimension of the plate used in SDR, an ANSYS model which could simulate the impact of rock in the centre of the plate was established by Fabien Delhomme. By using this model, some finite element analyses are carried out in the present paper. Firstly, a plate impacted by a block is numerically simulated, the numerical results obtained from different mesh sizes are compared and the accuracy of the finite element model is verified. Then, the dynamic response of the plate impacted at the boundary and in the medium part is computed. By analyzing the stress in rebar, the most dangerous region of impact of plate was found. For a rectangular plate, the most dangerous region is at the corner of the plate when a block drops in. Finally, the whole deformation process of the plate under dropping block was simulated and a simplified definition ( effect zone) to describe the deformation process in different positions of plate was given. From this study, it is found that the impact only affects heavily within the effect zone. 相似文献
57.
INTRODUCTION For moderate thickness plate containing notches or holes, neither plane stress nor plane strain theory can describe its true deformation states (Jin and Hwang, 1989). This well known drawback has mo- tivated many analytical and numerical studies carried out to determine the effect of plate thickness on the in-plane stress distribution. Pioneering work on the along depth stress components, i.e. the K-M gener- alized plane strain theory was proposed by Kane and Mindlin (1956)… 相似文献
58.
What is the nature of the force or mechanism that moves massive continents thousands of miles across? What causes violent earthquakes to displace huge landmasses abruptly? How could great mountain ranges like Himalayas and Alps rise to such incredible heights? What makes earth's interior so restless? Answers to some of these questions may lie in understanding the Earth's interior itself. 相似文献
59.
在本文中,功的互等法(RTM)被推广应用于求解基于Reissner理论的厚矩形板的弯曲问题,得到了在任意一点作用集中荷载矩形厚板弯曲问题的解析解,并给出了具有实价的计算结果。 相似文献
60.