内置环形耐压液舱周向连接形式应力分析

针对内置式耐压液舱结构的应力变化规律,对比分析了不同载荷工况下,两种不同液舱顶板结构形式及变截面肋骨对液舱壳板的变形和应力的影响。结果表明:对于不同的液舱顶板形式,变截面肋骨角度β存在最优值;在液舱周向范围一定的情况下,肋骨肋板间的连接形式对液舱顶板纵向应力影响显著,而β主要影响液舱顶板的周向应力。     

基于再起动特性优化的高超声速进气道设计

对不同内收缩段设计的高超声道流场进行了数值仿真研究,考查了下壁面水平倾角对进气道各性能参数特别是再起动特性的影响.结果表明,减小进气道不起动流场大规模分离区尾部所在下壁面的水平倾角,可以显著提高不起动流场的性能,大幅降低再起动马赫数,但也带来内收缩段长度增加,起动流场性能降低的缺点.为兼顾两者性能,提出了一种新的内收缩...     

楮墨实录书史事 笔锋托愤抒胸臆——《史记》实录精神与托愤精神的二重组合

文章以《史记》实录精神与托愤精神组合为突破口,阐述了实录精神、托愤精神的远源和在史文中的凸显,进一步挖掘二者之间相悖的二元性关系,从而揭示《史记》中所蕴含的这种文化悖论本身的深刻性、美感魅力以及难解的文化之谜。     

建筑装修石材干挂施工工艺火灾危险性分析及对策

我国内装修工程石材干挂工艺从设计到施工均未考虑进行防火设计，加之施工过程中存在很多不规范现象，致使该工艺存在很大的火灾危险性。分析了该工艺的火灾危险性，提出了相应的对策，供消防设计审核人员、装修工程设计及施工人员参考。     

Study on performance degradation and failure analysis of machine gun barrel

An increase in the use of the gun barrel will cause wear of the inner wall, which reduces the muzzle velocity and the spin rate of the projectile. The off-bore flight attitude and trajectory of the projectile also change, affecting the shooting power and the accuracy. Exterior ballistic data of a high-speed spinning projectile are required to study the performance change. Therefore, based on the barrel's accelerated life test, the whole process of projectile shooting is reproduced using numerical simulation technology, and key information on the ballistic performance change at each shooting stage are acquired. Studies have shown that in the later stages of barrel shooting, the accuracy of shooting has not decreased significantly. However, it is found that the angle of attack of the projectile increases as the wear of the barrel increases. The maximum angle of attack reaches 0.106 rad when the number of shots reaches 4300. Meanwhile, elliptical bullet hole has appeared on the target at this shooting stage. Through combining external ballistic theory with simulation results, the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the projectile. At the end of the barrel life, the projectile muzzle spin rate is 57.5% lower than that of a barrel without wear.     

滑膛身管内径测量仪研究

针对滑膛身管特殊测量环境，设计了一种新型的高精度火炮身管内径自动化检测系统。系统本体结构实现了模块化设计，采用电感式位移传感器和激光测距传感器作为测量器件，在专门设计的传动机构的带动下，对火炮身管内膛直径进行自动化测量。同时，设计了一套测试软件，在该软件的支持下，可以准确地测量身管任意截面内径尺寸的变化，并实现了数据快速实时处理和显示输出。