排序方式: 共有46条查询结果,搜索用时 15 毫秒
21.
The asymmetric deformation and eccentricity problems of near hemispherical diaphragm under the uniform surface load are quantitatively
characterized in the paper. The analysis is based on a 3D finite element analysis (FEA) model established according to elastic-plasticity
and large displacement nonlinear finite element method. Besides, the deformation experiments are taken to validate the reliability
of FEA model which shows that the simulation results are in good agreement with the experimental results. Then, three angle
parameters, deflection angle β, circumvolving angle θ and distributing angle γ, are introduced and expressed to characterize the asymmetric deformation and eccentricity quantitatively. According to the
angle parameters, the inversion processes of uniform thickness diaphragm and varying thickness diaphragm are calculated respectively.
The inversion process of varying thickness diaphragm is much steadier than that of uniform thickness diaphragm. The present
results show that the asymmetric deformation process can be characterized by curve of three angle parameters (β, θ, γ) exactly, the degrees of eccentricity can be indicated by the final value of deflection angle and the eccentricity position
can be characterized by the final values of the three angle parameters. 相似文献
22.
In this paper, the effects of hardening exponent, yield strength and elastic modulus on the deformability of near hemispherical
shells are investigated by means of finite element method and orthogonal experiment design. The largest eccentric angle during
the deformation process and thickness reduction after the deformation are introduced to estimate the deformability quantitatively
according to the deformation characteristics of near hemispherical shells. The results indicate that the hardening exponent
is the most influential parameter, followed by elastic modulus and yield strength. The shell exhibits good deformability when
the hardening exponent and elastic modulus are in the range of 0.1–0.125 and 70–108 GPa, respectively. 相似文献
23.
珠江电厂煤码头拟扩建1个7万t级卸煤泊位,改造建设1个1 000 t级和1个2 000 t级装煤泊位.本文就其装卸工艺方案设计要点及码头设备选型等进行分析介绍.
1 设计依据
为满足企业的生产发展需要,建立煤炭资源供给、运输、中转及营销网络一体化的经营体制,要求本工程卸煤泊位的计划任务量为650万t/a,装煤泊位的计划任务量为400万t/a.
本工程的设计代表船型为7万t级散货船和2 000 t级、1 000 t级散货驳船. 相似文献
24.
以某集装箱码头装卸系统改造工程为例,介绍说明集装箱码头改造在有限的条件下,对码头装卸设备、堆场等进行改造,提高了码头年通过能力,并有效降低了能耗,降低了装卸成本。 相似文献
25.
26.
配气机构是发动机的重要组成部分,文章对五十铃4JB1发动机的配气机构进行研究分析,通过将摇臂调整螺钉改进设计为液压挺杆,自动调节和控制气门间隙,避免摇臂和气门之间产生机械碰撞和敲击,减小了噪声,在生产中得到应用。 相似文献
27.
THE ROLE OF BRAIN-STEM DISCENDING INHIBITORY SYSTEM IN THE ANTINOCICEPTIVE EFFECT ELICITED BY MUSCLE SPINDLE AFFERENTS 总被引:3,自引:0,他引:3
usclespindleisdetectedtobenotonlythepro prioceptorbutalsothereceptorofacupuncture[1] .Previousstudiesinourlabrevealedthatactivatemus clespindleafferentsbystretchingthehindlimbmus clesofratssignificantlydepressedthenociceptivere sponses (C fibres evokedresp… 相似文献
28.
应用动态刚度矩阵法分析曲轴的动态特性.曲轴被简化为一系列的连续梁单元.在给定力和位移边界条件下,得出了考虑转动惯量和剪切变形影响的空间连续梁单元的动态刚度矩阵.总动态刚度矩阵按照常规有限元方法进行组装.采用Wittrick-Wlliams(W-W)算法和常规算法分别计算了曲轴系统的特征值和特征向量.应用本文方法、有限元方法以及相关实验数据分析了4缸直列内燃机曲轴的动态特性.通过比较,验证了文中方法的有效性和精确性. 相似文献
29.
30.
<正>2015年2月4日,川藏公路318国道上的通麦特大桥钢桁梁顺利合龙(见图1)。通麦特大桥位于川藏公路318国道西藏的通麦镇,大桥跨越湍急的西藏易贡藏布江,为单塔单跨地锚式钢桁架空间缆悬索桥,主跨256 m。由于受环境等条件限制,采用了地锚式的空间缆,且部分主缆位于主桁上弦杆下方。在该桥锚碇施工中,在高寒地带首次实现了无降温管的大体积重力锚碇混凝土施工;采用了轨道式牵引系统安装空间缆,解决了空间缆施工容易出 相似文献