共查询到20条相似文献，搜索用时 922 毫秒
1.
2.
以一金属-梯度材料-陶瓷的复合圆简为研究对象，研究了功能梯度材料组份连续变化论况下的温度分布和热应力分布规律；并根据强度理论，就ZrO2Ti－6AI－4V梯度材料的热应力分布进行了组份分布的统和特性设计．计算结果表明：金属-陶瓷梯度材料具有较好的热应力缓和性，且其模型具有较广的适用性． 相似文献
3.
采用坐标变换法导出了圆筒空间轴对称问题稳态热传导温度分布的关系式 .由圆筒内外侧冷热流体介质沿轴向的温度分布计算圆壁内各处温度分布 .计算结果与实验结果吻合很好 .所得公式的适用条件与多数实际情况一致 ,可用于实际热传导工程计算 .此方法计算工作量小 ,结果准确 相似文献
4.
利用有限元分析软件ANSYS Workbench对某内压筒体沿周向开设矩形排孔的结构进行有限元分析,得到该结构的应力分布状况和最高应力水平,并据标准对此结构进行了强度评定。分析结果表明,沿筒体轴向因开孔致应力集中的影响范围较小,而周向各接管开孔应力集中的影响互相叠加,其范围遍布筒体的整个周向,最大应力分布在各接管拐角和各接管与筒体的角焊缝处,故矩形接管的焊缝应全焊透且需进行表面渗透检测,以满足JB4730I级合格标准,并避免安排在拐角处。 相似文献
5.
为了解不同空调风机的内流机制,采用数值分析和PIV实验研究相结合的方法对空调用贯流风机和轴流风机内部复杂的旋涡流动现象进行了研究。结果表明:空调壁挂机用贯流风机内部偏心涡沿轴向具有明显的三维分布特性,偏心涡径向位置沿轴向几乎没有变化,其周向位置沿轴向不断改变。贯流风机偏心涡卷吸区域随负载提高而增强。高负载时,偏心涡更加靠近叶轮中心和蜗壳方向。空调室外机用开式斜流风轮的叶尖涡产生于距叶片前缘1/4区域,靠近吸力面。叶尖涡随风轮转速的提高而增强,并沿着与风轮旋向相反的方向朝下游发展。 相似文献
6.
发动机气缸盖是较易发生疲劳破坏的发动机零件之一,其机械疲劳强度与螺栓预紧力之间存在关系。利用Solidworks建立气缸的简化模型,导入Workbench中进行静力学分析：在Workbench中建立两个不同的载荷环境,利用组合求解功能对螺栓预紧力和气缸盖受到气缸内气体的最高爆发压力进行线性组合,完成非比例载荷的疲劳寿命计算,得到不同螺栓预紧力下的气缸盖疲劳寿命曲线,由此获知螺栓预紧力和气缸盖疲劳寿命之间的关系,这为合理选择螺栓预紧力提供了依据。 相似文献
7.
文章以作用于梁上的横向分布力集度与剪力、弯矩的微分关系为基础,归纳总结了几种荷载作用下剪力图、弯矩图的特征。掌握这些特征就能不写内力方程而根据外力直接画出相应的剪力图和弯矩图。 相似文献
8.
李彦民 《福建工程学院学报》2019,(6):539-544
为研究地面线路运营对下穿盾构隧道结构的影响规律,基于相似比理论建立室内大型试验模型,模拟上部列车荷载作用下土层及其内部盾构隧道结构的受力变形过程,总结变形规律。结果表明,模型试验能够较好地反映外部荷载影响下土层以及内部盾构隧道结构的受力和变形特性;地表列车荷载在土层传递过程中,同一层面上沿地面线路方向的土压力大于两侧土压力,远离线路的地层受列车荷载影响相对较小,同一竖向截面土压力变化量由上至下逐渐减小,即外部荷载对浅层土的影响明显大于深层土;盾构隧道在地表列车行驶过程中,环向出现背车面受拉迎车面受压的受力特性,呈斜向压扁,纵向应变从中间交叉点向盾构隧道两侧逐渐减小,呈下凹压弯;盾构隧道埋深越小,受地表荷载影响越显著,增大一倍埋深对应纵向应变最大值减小约44.5%。 相似文献
9.
LU Xiao bing YANG Zhen sheng ZHANG Jia hua 《上海大学学报(英文版)》1999,3(4):270-273
１ Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｔｈｅｄｙｎａｍｉｃｄｅｎｓｉｆｉｃａｔｉｏｎａｎｄｅｘｐｌｏｓｉｖｅｔｅｃｈｎｉｑｕｅｓａｒｅｏｆｔｅｎｕｓｅｄｔｏｓｔｒｅｎｇｔｈｅｎｔｈｅｓｏｉｌｆｏｕｎｄａｔｉｏｎ［１,２］．Ｂｕｔｔｈｅｙｏｆｔｅｎｌｅａｄｔｏｔｈｅｉｎｓｔａｂｉｌｉｔｙｏｆｆｏｕｎｄａｔｉｏｎａｎｄｔｈｅｆａｉｌｕｒｅｏｆｓｔｒｕｃｔｕｒｅｓｎｅａｒｂｙ．Ｔｈｅｒｅｆｏｒｅ,ｉｔｉｓｉｍｐｏｒｔａｎｔａｎｄｐｒａｃｔｉｃａｌｔｏｓｔｕｄｙｔｈｅｉｎｓｔａｂｉｌｉｔｙｏｆｓｏｉｌｆｏｕｎｄ… 相似文献
10.
"露露"易拉罐是一种薄壁圆筒,但由于存在纵向连接缝,破坏了结构的轴对称性.利用有限元法对有纵向连接缝的圆筒进行了特征值屈曲分析,计算结果与实验值能较好地吻合.对有、无纵向连接缝圆筒临界压力的有限元计算结果进行了比较,发现当主要考虑筒体的侧向失稳时,该连接缝对其失稳性能影响很小,可用做外压圆筒稳定性实验的试件. 相似文献
11.
The equations of fluid statics derive from the fact that in a stationary fluid only normal stress (pressure) is present and
tangential stresses are absent. In this article we derive equations for variation of pressure in a static fluid or in one
that is moving as a rigid body. Also, we show that surfaces of constant pressure and constant density should coincide. Various
types of instabilities related to submerged bodies and multi layerd fluids are briefly discussed. 相似文献
12.
13.
Ten slender steel reinforced cencrete (SRC) composite columns are tested under eccentric loading conditions.Effects of concrete strength, slenderness of columns and eccentricity of the axial load are studied. The load-carrying capacity is reduced with increased slenderness ratio and eccentricity. Concrete strength has no obvious influence on eccentrically loaded columns. Then, a nonlinear numerical method of pin-ended slender columns is also presented. This method is applicable for determining the material failure load or buckling failure load of a slender steel reinforced concrete composite column. In this method both material and geometric nonlinearities are taken into account. The results of numerical analysis accord well with the test results. The test results are also compared with the results predicted by ACI318-05 and the China Specifications. 相似文献
14.
The National Swimming Center built for the 2008Beijing Olympic Games applies the polyhedron spatialframe structure, which is based on the foam physicstheory[1]. Its simple geometry is a square box of 170m×170 m×29 m. It can hold 17 000 people, theroof o… 相似文献
15.
根据荷载集度与剪力、弯矩之间的导数关系,找出了绘制内力图的规律,应用此规律画剪力图和弯矩图不必列内力方程,只需依据梁在不同荷载作用下剪力图及弯矩图的图形特征计算出控制截面的内力值,即能简便、快捷地画出内力图。 相似文献
16.
Experiments of silt rock subjected to coupling loads were carried out on tailormade equipment. With a constant dynamic load, the behaviors of eight sets of siltite specimens were investigated with different axial static loads. The experimental results show that the modulus of the specimens under coupling loads increases at first and then decreases with the increase of axial static pressure. The failure model of the specimens also varies. Keeping the dynamic load constant, when the axial static pressure is low, the specimen breaks in two simply. With the increase of axial static pressure, the cone-shaped fragment appeares. When the axial static pressure reaches 90% of the static strength of rock, the specimen smashes into amount of small fragments. 相似文献
17.
INTRODUCTION Recently, more and more investigations have been conducted on multilayer piezoelectric media. Kharouf and Heyliger (1994) and Heyliger and Ra- mirez (2000) dealt with the free vibration problems of laminated piezoelectric cylinders and discs, respec- tively. Chen (2000) considered the free vibration of (multilayer) nonhomogeneous piezoceramic hollow spheres by employing a separation formulation for displacements. Chen (2001) developed a state-space method for free vibration … 相似文献
18.
ZHOU Zilong LI Xibing HONG Liang MA Chunde 《天津大学学报(英文版)》2006,12(B09):205-209
Experiments of silt rock subjected to coupling loads were carried out on tailormade equipment. With a constant dynamic load, the behaviors of eight sets of siltite specimens were investigated with different axial static loads. The experimental results show that the modulus of the specimens under coupling loads increases at first and then decreases with the increase of axial static pressure. The failure model of the specimens also varies. Keeping the dynamic load constant, when the axial static pressure is low, the specimen breaks in two simply. With the increase of axial static pressure, the cone-shaped fragment appeares. When the axial static pressure reaches 90% of the static strength of rock, the specimen smashes into amount of small fragments. 相似文献
19.
欧智菁俞杰林上顺王金泽 《福建工程学院学报》2019,(6):511-517
以黄桷湾特大桥为工程背景,选取轴压比、梁墩刚度比、系梁布置形式及柱肢混凝土强度等级为设计参数,应用Midas Civil有限元软件构造了20座三跨对称桥梁计算模型。研究E1地震作用下钢管混凝土双肢格构墩连续梁桥主要控制截面参数地震响应,探讨各设计参数对钢管混凝土双肢格构墩连续梁桥抗震性能的影响规律,并对全桥进行优化验证。研究结果表明:轴压比对地震作用下结构内力和位移有一定影响,建议控制在0.15~0.25;梁墩刚度比对结构的抗震性能影响较大,控制在4.08~10.90时结构的内力分布更加合理;核心混凝土的强度在C40~C50时取值较为合理。 相似文献
20.
Nonlinear bending of cantilever incompressible poroelastic beams subjected to a uniform load is investigated with the constraint that fluid flow is only in the axial direction. The governing equations for large deflection of the poroelastic beam are derived from theory of incompressible saturated porous media. Then, nonlinear responses of a cantilever beam with impermeable fixed end and permeable free end are examined with the Galerkin truncation method. The deflections and bending moments of the poroelastie beam and the equivalent couples of the pore fluid pressures are shown in figures. The differences of the results between the large deflection and the small deflection theories are analyzed. It is shown that the results of the large deflection theory are smaller than those of the small deflection theory, and the time needed to approach their stationary states for the large deflection theory is shorter than that for the small deflection theory. 相似文献