海船闸气幕防咸设计

为指导船闸气幕防咸设计,本文将经典Abraham方法和Keetels数据进行比较.结果发现,Abraham方法偏保守.基于Keetels数据,本文提出一种新的半经验公式,以获得更准确的供气量.     

声自导鱼雷对抗气幕弹技术方法探讨

目前世界各国舰艇装备了大量的水声对抗器材,用于扰乱或中断鱼雷自导对潜艇的跟踪或直接欺骗鱼雷的攻击。气幕弹由于其结构简单,成本低廉,使用方便等特点已成为水声对抗战中普遍使用的对抗器材。文章对气幕弹干扰鱼雷的机理进行了探讨,分析了气幕弹的战术使用方法,重点讨论了声自导鱼雷对抗气幕弹的技术方法,包括识别气幕、判断逃逸潜艇位置、设计对抗弹道。文章给出了一种典型的对抗气幕弹的方法。     

基于生态系统理论的智能港口集装箱运输工匠型人才培育模式

人工智能技术应用是自动化码头构建智能航运生态的引擎,加快培育集装箱运输工匠型专业人才则为智能港口提供智力支撑和人才保证.以文献研究与实证研究为基本主线,归纳演绎适应以互联网、大数据、云计算和自动感应技术为主要特征的智能港口集装箱运输工匠型人才内涵和特征:行为认识、行业自觉、思维创新、技能精进和实践养成.提出其培育路径:...     

工匠精神指导下产教融合校企合作的课程体系构建研究

在工匠精神指导下,以戴姆勒铸星教育项目为平台,以校企合作产教融合为育人理念,以双元育人灵活多样的教学方式为原则,校企双方对人才培养方案和课程体系进行实践性构建研究。坚持以生为本,学以致用,以提升教育教学效果和教学质量为最终目标。通过建立人才培养模式的构建和课程体系的优化,推动职业本位工匠精神的塑造,深化产教融合,实现人才培养。     

Effect of microbubbles on the structure of turbulence in a turbulent boundary layer

The time-averaged velocity and turbulence intensity distributions were measured by a laser Doppler velocimeter in a turbulent boundary layer filled with microbubbles. The void fraction distribution was also measured using a fiber-optic probe. The velocity decreased in the region below 100 wall units with an increase in bubble density. This led to a decrease in the velocity gradient at the wall, which was consistent with a decrease in shearing stress on the wall. The turbulence intensity in the buffer layer increased at a low microbubble density, and then began to decrease with an increasing microbubble density. Based on the present measurements, the mechanism of turbulence reduction by microbubbles is discussed and a model is proposed. Received for publication on Dec. 3, 1999; accepted on April 18, 2000     

莎士比亚的悲剧美学思想

莎士比亚的悲剧作品是欧洲近代悲剧创作的最高成就。本文对莎士比亚的悲剧美学思想进行了全面的分析。本文从莎士比亚的悲剧人物的美学特征、他所建构的悲剧冲突和悲剧的死亡的结局等方面论述了莎士比亚悲剧美学思想的特点，说明了他对后世悲剧创作的深远影响。     

数值仿真技术在汽车涂装工艺中的应用

针对某款新开发车型其发罩外板内表面前端电泳效果差的问题,利用数值仿真技术对其进行分析。发现主要是由于前端设计不合理,在电泳时形成死腔,产生大的气泡从而导致电泳不上的问题。在增加一个简单的排气工艺孔后,结果大为改善。     

水下爆炸气泡脉动作用下细长加筋圆柱壳的鞭状响应分析

细长加筋圆柱壳是潜艇耐压壳体的主要结构,其在水下爆炸载荷之下发生的鞭状运动是潜艇结构破坏的主要因素之一.为了考察不同的因素对于细长加筋圆柱壳鞭状响应的影响,该文将圆柱壳简化为一根变截面的梁,用双重渐进近似法(DAA)描述了结构的动态变形与瞬态流场的耦合作用,从弯矩的角度的考察了水下爆炸第一次气泡脉动载荷对结构鞭状响应的贡献,总结了圆柱壳上的弯矩随潜深,爆距,爆炸方位角变化的规律.研究结果有助于进一步了解水下爆炸作用下潜艇的鞭状动响应特征,并用以改进潜艇的抗冲击设计.     

楚人精神对当代湖北建设的启示

湖北是文化大省,但不是文化强省。是经济大省,但不是经济强省。"中部崛起"是2005年中央经济工作的六项任务之一。如何抓住这一历史机遇,促进湖北建设,使之在中部崛起,是本文研究的目的。本文将联系楚人精神谈其对湖北建设的一些启示。     

Characteristics of a bubble jet near a vertical wall

A numerical model of a coupled bubble jet and wall was built on the assumption of potential flow and calculated by the boundary integral method. A three-dimensional computing program was then developed. Starting with the basic phenomenon of the interaction between a bubble and a wall, the dynamics of bubbles near rigid walls were studied systematically with the program. Calculated results agreed well with experimental results. The relationship between the Bjerknes effect of a wall and characteristic parameters was then studied and the calculated results of various cases were compared and discussed with the Blake criterion based on the Kelvin-impulse theory. Our analyses show that the angle of the jet＇s direction and the pressure on the rigid wall have a close relationship with collapse force and the bubble＇s characteristic parameters. From this, the application range of Blake criterion can be determined. This paper aims to provide a basis for future research on the dynamics of bubbles near a wall.