基于AutoCAD的烘干筒底盘装配图的设计

在介绍烘干筒的结构和原理的基础上,对烘干筒底盘参数进行设计,并利用二次开发手段对底盘进行程序设计,从运行结果看,能实现对烘干筒底盘装配图的自动设计.     

超临界1000 MW汽轮机高压缸温度场及应力分析

应用有限元分析程序分别计算分析了超临界1 000 MW汽轮机高压内外缸稳态运行时的温度场、热应力、机械应力及综合应力,并将高压内外缸分别计算的结果与高压内外缸合在一起进行计算的结果进行了比较.得出了该汽轮机高压缸较全面的强度数据,为汽缸的安全性评定和寿命预测提供了技术依据.     

Some further aspects of the löwner-ordering antitonicity of the moore-penrose inverse

A survey is given of known proofs of the antitonicity of the inverse matrix function for positive definite matrices w.r.t. the Lowner partial ordering, and of the corresponding result for the Moore-Penrose inverse of nonnegative definite matrices [the theorem of Milliken and Akdeniz (1977)]. A short new proof of the latter result is obtained by employing an extremal representation of a nonnegative definite quadratic form. Another proof of this result involving Schur complements is also given, and is seen to be extendable to the case of symmetric (not necessarily nonnegative definite) matrices. A geometrical interpretation of Milliken and Akdeniz's theorem is presented. As an application, the relationship between the concepts of greater (maximum) concentration and smaller (minimum) dispersion is considered for a pair (class) of vector-valued statistics with possibly degenerate distributions.     

Bayes Prediction for a Heteroscedastic Regression Superpopulation Model Using Balanced Loss Function

We consider Prais–Houthakker heteroscedastic normal regression model having variance of the dependent variable same as square of its expectation. Bayes predictors for the regression coefficient and the mean of a finite population are derived using Zellner's balanced loss function. Bayes predictive expected losses are obtained and compared with those of classical predictors and Bayes predictors under squared error loss function to examine their loss robustness.     

A Nonstationary Cylinder–Based Model Describing Group Dispersal in a Fragmented Habitat

□ A doubly nonstationary cylinder-based model is built to describe the dispersal of a population from a point source. In this model, each cylinder represents a fraction of the population, i.e., a group. Two contexts are considered: The dispersal can occur in a uniform habitat or in a fragmented habitat described by a conditional Boolean model. After the construction of the models, we investigate their properties: the first and second order moments, the probability that the population vanishes, and the distribution of the spatial extent of the population.     

车载高压天然气钢瓶的结构优化

文章对34CrMo4钢质车载天然气气瓶进行了水压爆破试验和水压疲劳试验,运用有限元软件ANSYS分析了气瓶的爆破压力与疲劳寿命。并通过ANSYS的优化模块对气瓶进行了结构优化设计。分析结果表明文中的计算方法准确,可作为工程上CNG气瓶结构设计时的参考方法。     

振筒式传感器准确度目标规划优化模型及解

用改进单纯形算法求解振筒式压力传感器准确度的优化模型．经计算机解算求得最佳拟合方程及国产某振筒式压力传感器的准确度数据     

基于灰色统计方法的筒形件拉深缺陷分析与对策

本文基于灰色统计方法综合计算处理了多位冲压领域专家的意见,根据计算结果对筒形件拉深缺陷的解决方法按照重要程度排序,得出了一个制品缺陷与主要解决方法的对应顺序表,从而为筒形件拉深加工中克服缺陷的产生提供参考依据.     

圆柱壳开孔补强结构的有限元分析

使用ANSYS软件计算同一筒径,不同开孔直径壳体,共六个模型的应力集中系数.按等面积补强法计算出以上模型分别采用补强圈补强和厚壁接管补强各自的厚度,建立相应的模型,求出应力集中系数.有限元的分析方法可以证明:在局部区域内产生较大的塑性变形时采用补强圈或厚壁接管补强,均可有效的改善孔边的应力集中,相同壳体直径,开相同大小的孔时,接管补强后的应力集中系数小于补强圈补强的应力集中系数.     

数值模拟圆柱统流旋涡生成、分离及演化

本文应用有限差分方法求解涡量－流函数形式的Ｎ－Ｓ方程，数值模拟了圆柱瞬时起动后流动分离，旋涡生成、脱落以及随时间推进涡街产生和长期非定常演化过程，包括对称涡的生成，二次涡形成的α结构及卡门涡街等．本文方法效率较高，数值模拟结果与实验结果吻合较好，可推广到模拟其他复杂钝体在中等或高雷诺数下的非定常绕流问题．