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乌东德水电站表孔体型优化研究 被引量:4
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作者 韩喜俊 胡清义 +2 位作者 宛良朋 韩松林 潘洪月 《人民长江》 北大核心 2020年第3期131-135,共5页
乌东德水电站坝址处河谷狭窄,覆盖层深厚,施工详图设计阶段拱坝厚高比增加,表、中孔相对位置发生变化,存在表孔自由溢流水体击打中孔弧门、表中孔水舌碰撞后形成的横向溅水冲击透水边坡及水垫塘底板冲刷较深等问题。通过1∶50水工整体... 乌东德水电站坝址处河谷狭窄,覆盖层深厚,施工详图设计阶段拱坝厚高比增加,表、中孔相对位置发生变化,存在表孔自由溢流水体击打中孔弧门、表中孔水舌碰撞后形成的横向溅水冲击透水边坡及水垫塘底板冲刷较深等问题。通过1∶50水工整体模型试验及方案比选,对表孔出口位置、型式进行了优化研究,使表孔水舌横向扩散,纵向分层明晰,表中孔碰撞消能后水垫塘底板冲刷轻微,边坡横向溅水强度基本与自然降水相当。研究成果可为工程设计及安全运行提供技术支撑。 展开更多
关键词 体型优化 底板冲刷 横向溅水 降雨强度 乌东德水电站
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高差动坎在拱坝泄洪表孔中的应用研究 被引量:4
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作者 蒋俏芬 尹进步 +1 位作者 何军龄 吴宝琴 《水电能源科学》 北大核心 2017年第3期78-81,共4页
针对中小型拱坝表孔大流量泄洪时存在的向心集中问题,结合某工程泄洪表孔消能工,采用数值模拟与模型试验相结合的方法对其不同体型的方案进行了对比分析。结果表明,表孔大流量泄洪时,设置高差动坎体型与窄缝式及低差动式挑坎相比,水舌... 针对中小型拱坝表孔大流量泄洪时存在的向心集中问题,结合某工程泄洪表孔消能工,采用数值模拟与模型试验相结合的方法对其不同体型的方案进行了对比分析。结果表明,表孔大流量泄洪时,设置高差动坎体型与窄缝式及低差动式挑坎相比,水舌纵向拉开更加明显,并伴有一定的横向扩散,水舌落点分布均匀,对河床形成的冲击压力较小且分散,消能效果较为显著。此外,其空蚀破坏可能性也不大,可见高差动坎体型总体安全、合理。 展开更多
关键词 表孔优化 高差动挑坎 大单宽泄流 冲击压力
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Effects of deposition parameters on HFCVD diamond films growth on inner hole surfaces of WC-Co substrates 被引量:3
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作者 王新昶 林子超 +1 位作者 沈彬 孙方宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期791-802,共12页
Deposition parameters that have great influences on hot filament chemical vapor deposition (HFCVD) diamond films growth on inner hole surfaces of WC?Co substrates mainly include the substrate temperature (t), carbon c... Deposition parameters that have great influences on hot filament chemical vapor deposition (HFCVD) diamond films growth on inner hole surfaces of WC?Co substrates mainly include the substrate temperature (t), carbon content (φ), total pressure (p) and total mass flow (F). Taguchi method was used for the experimental design in order to study the combined effects of the four parameters on the properties of as-deposited diamond films. A new figure-of-merit (FOM) was defined to assess their comprehensive performance. It is clarified thatt,φandp all have significant and complicated effects on the performance of the diamond film and the FOM, which also present some differences as compared with the previous studies on CVD diamond films growth on plane or external surfaces. Aiming to deposit HFCVD diamond films with the best comprehensive performance, the key deposition parameters were finally optimized as:t=830 °C,φ=4.5%,p=4000 Pa,F=800 mL/min. 展开更多
关键词 hot filament chemical vapor deposition diamond film inner hole surface Taguchi method deposition parameter optimization
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Hybrid Surface Mesh Adaptation for Climate Modeling
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作者 Ahmed Khamayseh Valmor de Almeida Glen Hansen 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第4期410-434,共25页
Solution-driven mesh adaptation is becoming quite popular for spatial error control in the numerical simulation of complex computational physics applications,such as climate modeling.Typically,spatial adaptation is ac... Solution-driven mesh adaptation is becoming quite popular for spatial error control in the numerical simulation of complex computational physics applications,such as climate modeling.Typically,spatial adaptation is achieved by element subdivision (h adaptation) with a primary goal of resolving the local length scales of interest.A sec- ond,less-popular method of spatial adaptivity is called'mesh motion'(r adaptation); the smooth repositioning of mesh node points aimed at resizing existing elements to capture the local length scales.This paper proposes an adaptation method based on a combination of both element subdivision and node point repositioning (rh adaptation). By combining these two methods using the notion of a mobility function,the proposed approach seeks to increase the flexibility and extensibility of mesh motion algorithms while providing a somewhat smoother transition between refined regions than is pro- duced by element subdivision alone.Further,in an attempt to support the requirements of a very general class of climate simulation applications,the proposed method is de- signed to accommodate unstructured,polygonal mesh topologies in addition to the most popular mesh types. 展开更多
关键词 surface mesh generation mesh adaptation mesh optimization climate modeling.
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