用能量法计算隧洞出口挑流下游基岩冲刷

高土石坝的由导流洞改建而来的永久性泄洪洞，由于导流洞的高程低，泄洪落差大、流速高，下游的基岩冲刷问题引起人们的重视。能量法是计算基岩冲刷深度的较新方法，根据参证坝址(原型已建工程)和待建坝址的平均水股剩余能量与冲刷深度的关系用冲刷能量指标ESI来估算大坝下游岩基冲深。将能量法应用于紫坪铺1^#泄洪排沙隧洞挑流基岩冲刷中，并将计算结果与经验公式和试验数据比较，证明此法可行，且效果较好。     

影响冷弯型槽钢临界弯曲角因素综合分析

计算、分析了带材弹性模量，槽钢腿部长度，腰部宽度，厚度，强度极限和弹性极限对冷弯型槽钢临界弯曲角的影响，其结果对提高产品质量，降低生产成本有参考价值。     

粉体气力输送时弯管的阻力特性及计算方法研究

本文首先综述分析了国内外对不同弯曲曲率半径及角度弯管的阻力特性研究，然后结合作者在多相流动试验台上对４５°、９０°、１１０°、１５０°角度及Ｒ／Ｄ＝２、２．５和３所进行的不同试验结果，采用多变量回归分析法得出适合于计算不同曲率半径和角度的弯管局部阻力系数通用公式，其计算结果与试验值较吻合．     

四点弯疲劳试验尺寸效应及MA760疲劳特性研究

考虑到四点弯疲劳试验在疲劳裂纹启裂及早期扩展行为研究中的优点，本文设计并使用了一个四点湾疲劳加载装置。在不同的内跨距／试样厚度比值（d／H）及外跨距／内跨比值（L／d）下，经有限元计算结果表明：纯弯曲段内的表面应力分布并不是均匀的。计算结果有效地解释了本文及有关文献中的实验结果，文中据此给出了四点弯疲劳试样的推荐尺寸。在室温及高温（750℃）下，对锦基超强合金MA760进行四点弯疲劳试验结果表明：该材料具有很好的抗疲劳裂纹启裂能力，但其抗裂纹扩展能力很差；该材料对内部夹杂物的敏感性与环境温度及试样相对厚度密切相关。     

多级工程模糊优选在土石坝溢洪道选型中的应用

针对溢洪道设计中经常遇到的方案优选问题，提出将多因素、多层次模糊优选理论引入溢洪道的设计选型工作中。对影响因素复杂、确定隶属函数主观因素较强的情况，引入因素的优先关系法来确定优选矩阵的隶属度，这样减少了确定隶属函数的人为影响，通过此优选模型利用影响溢洪道选型的主要因素对多种溢洪道设计型式进行了多级模糊综合优选决策，得到了比较理想的决策结果，为溢洪道设计选型提供了新的思路。     

叠片式吊钩的强度计算

用于铸造起重机的龙门钩除了受到起吊载荷的作用，还受到吊运的液态金属的高温辐射，不仅承受弯曲应力、扭转应力、剪切应力还有高温钢水辐射产生的热变应力等，通过对几个危险截面的强度分析，以最终确定吊钩组的截面尺寸。     

弯道零件的斜孔加工

对于零件弯道的两个3空间斜孔,原通过组合夹具定位后,采用划线加工,加工质量不能满足图纸要求。针对该问题,指出了划线加工的不足,并采用新的加工方法,即在立卧转换加工中心上,开发并运用其潜在的"循环19(即零点跟踪)"功能,从而显著提高了整机的性能。     

山溪坝后式取水及明渠弯道除沙方式研究

随着我国水利水电工程建设的发展,水电站分布越来越集中于偏远山区,供水系统往往需自行建设。为了解决工程建设施工及生活用水问题,通常是将工程附近水源水质较好的山溪作为取水点,并经简单沉沙处理后投入使用。传统的坝前式山溪取水及大型沉沙池除沙普遍面临着汛期取水头部易被泥石流淤积、山溪内施工部位狭窄等问题,根据弯道环流原理,结合杨房沟水电站供水系统取水头部设计及运行使用经验,研究验证了坝后式取水代替传统的坝前式取水,以及明渠除沙代替大型沉沙池除沙方式的实际效果。实践表明,新的取水方式可以满足抗淤能力强、施工占地少,同时除沙能力理想的要求,可为今后类似情况下山溪取水及除沙方式的选择提供参考。     

Numerical study on erosion of a pipe bend with a vortex chamber

Abrasive erosion at bend is a common issue in gas–solid pneumatic system. Vortex chamber design is one of the specialized designs that offers promising prospect at reducing erosion. The performance of design is still relatively unknown in the literature. The aim of this work is to study the effect of basic erosion variables such as the flow Reynolds number, the particle Stokes number, and the vortex chamber size. The results show that the vortex chamber always reduces the erosion in comparison to the common radius bend, and it is more effective at higher Reynolds number. Increasing the chamber size reduces the erosion but the most significant reduction happens when the chamber size to the pipe diameter ratio is increased from 1 to 1.25. The chamber size influences the erosion differently at different Reynolds number. Trends describing these effects were obtained through trial-and-error approach. The particle Stokes number has nonunique effect on erosion. Increasing Stokes number through increasing Re increases the erosion while increasing Stokes number through decreasing Re_p decreases the erosion.     

Discharge characteristics of orifice spillway under oblique approach flow

Orifice type spillways are provided in the dam at lower level for facilitation in flushing of the sediment from the reservoir in addition to spilling the flood water. However, in most of the hydraulic structures, particularly in the earthen and rockfill dams, the spillway is not a part of the dam and it is provided on either of the banks of the river which results in oblique approach flow to the spillway that likely to affect the discharging capacity of the spillway. Presented in this paper is an experimental study for discharge characteristics of orifice type spillway under straight and oblique approach flow. Analysis of data indicates that discharge through the spillway decreases with increase of obliquity of the flow. The effect of the obliquity has been quantified and discharge equations for one, two and three simultaneous opening of the bays have been proposed.