烹饪机器人双压强火力数值计算与实验

为实现烹饪机器人无级火力强度调节,进行鼓风式燃气燃烧器的双压强火力数值计算与实验.建立燃烧器引射管的基本方程、组分输运方程和湍流方程等数学模型;应用流体力学分析软件FLUENT建立引射管二维轴对称气体运动模型,确定了边界条件、初始状态和有限速率化学反应模型;根据燃烧器喷嘴中心高压空气压力值对可燃气体速度提升和引射吸入空...     

Relationship between diameter of split Hopkinson pressure bar and minimum loading rate under rock failure

In order to investigate the relationship between bar diameter and loading rate of the split Hopkinson pressure bar（SHPB） setup under the failure of rock specimen and realize the medium strain rate loading of specimen, new SHPB setups with different elastic bar＇s diameters of 22, 36, 50 and 75 mm were constructed. The tests were carried out on these setups at different loading rates, and the specimens had the same diameter of elastic bars and same ratio of length to diameter. The test results show that the larger the elastic bar＇s diameter is, the less the loading rate is needed to cause specimen failure, they show good power relationship, and that under the same strain rate loading, specimens are broken more seriously with larger diameter SHPB setup than with smaller one.     

盐度和压强对布里渊雷达遥测海洋温度的影响

为提高布里渊激光雷达测量较深海域的温度精度,建立了以布里渊频移、盐度和压强为独立变量的海水温度的经验方程,定量分析了温度随盐度、压强、布里渊频移的变化关系,讨论了盐度、压强以及布里渊频移对海水温度测量精度的影响,并计算了该方法测量温度的精度.研究表明利用布里渊散射测量温度受海水盐度和压强分布的影响较大,其测量精度亦受到限制,约为0.4℃.因此实际测量时应同时获得被测处的盐度及压强值,这样布里渊雷达测量海洋温度的精度将会提高到0.05℃.     

非对称三岔管水力特性数值计算与流态分析

利用k-ε紊流数学模型对溧阳抽水蓄能电站非对称三岔管的水力特性进行了三维数值计算,分析了不同工况下岔管的流速和压强分布及水头损失系数,并将水头损失系数的计算值与实验值进行比较.结果表明,两者协调一致、相互验证,岔管流量不对称时流态较差,不运行支管内有明显回流,运行时应尽量避免此种工况.     

瓦斯研究史上的两个新定律

先通过实例计算,再根据瓦斯分子压强平衡方程进行分析,得出在瓦斯研究史上的两个新定律。     

理想气体近似条件的研究

理想气体是热力学和统计物理学中一个基本的、重要的研究对象,实际气体在一定条件下可近似看作理想气体,用理论计算方法,估算出其近似条件.     

浅析初中物理液体压强教学过程中常见问题及对策

液体压强部分是初中物理教学过程中的重点和难点,不论是在考试中还是在日常生活中它的应用范围都很广。液体压强部分涉及的知识点较抽象,学生理解起来比较困难,造成液体压强教学过程中仍存在一些亟待解决的问题。从液体压强教学过程中存在的问题出发,提出相关改进措施。     

喷雾淀粉用于纸板生产

近几年来 ,造纸助剂发展十分迅速 ,化学助剂在造纸过程中起到的作用越来越受到广大造纸工作者的重视。目前 ,国内开发出的ＨＣＰ系列和ＨＣＴ系列喷雾淀粉 ,比较实用。该产品为白色粉末状 ,用冷水可以直接分散成悬浮液 ,能在常温干燥条件下长期贮存不发生霉变 ,应用方便。喷雾淀粉是提高纸板的挺度、环压强度、层间结合力及表面强度的有效助剂 ,其应用机理是淀粉喷到纸中以后 ,在烘缸干燥过程中起到胶化作用 ,增强了纤维之间的结合力。目前大多数纸板厂增加了废纸的利用量。经在漯河市板纸厂多次反复试验发现 ,废纸浆成分比较复杂 ,杂质含量…     

整体式圆膜片压强传感器的有限元分析和性能研究

本文介绍了三款整体式圆膜片压强传感器，进行了有限元分析，同时介绍了在制造压强传感器时的一些工艺难点和解决办法。     

Computational analysis for prediction of pressure of PWR presurizer under transient conditions

A computer model has been developed for prediction of the pressure in the pressurizer under transient conditions.In the model three separate thermodynamic regions which are not required to be in thermal equilibrium have been considered.The mathematical model derived from the general conservation equations includes all of the important thermal-hydraulics phenomena occurring in the pressurizer,i.e.,stratification of the hot water and incoming cold water,bulk flashing and condensation ,wall condensation,and interfacial heat and mass transfer,etc.The bubble rising and rain-out models are developed to describe bulk flashing and condensation.respectively.To obtain the wall condensation rate,a one-dimensional heat conduction equation is solved by the pivoting method.The presented model will predict the pressure-time behavior of a PWR pressurzer during a variety of transients.The results obtained from the propesed mathematical model are in good agreement with available data on the CHASHMA nuclear power plant‘s pressurizer performance.