2400高强瓦楞原纸机流浆箱的设计探讨

２４００高强瓦楞原纸机流浆箱是根据瓦楞纸浆容易产生浮浆、泡沫及絮聚的流送特性，对其布浆、扩散、整流及结构从流体力学的角度进行了探讨，认为该流浆箱使用在抄速１５０ｍ／ｍｉｎ左右的纸机上，完全可以获得良好的、稳定的扩散浆流。     

不对称出口导流器的射流式喷灌泵优化研究

为改善射流式喷灌泵的性能,提高泵的效率。本文设计了一种有2个出口的不对称导流器,可以加快泵内的气液混合与分离。通过正交试验和数值模拟方法,得到叶轮与导流器中截面多方案的空气体积分布云图,分析其气液混合与流动规律,研究导流器出口1角度θ、导流器出口2角度α和基圆直径D3对喷灌泵性能的影响,并对数值计算结果进行极差分析。研究结果得出方案4的导流器几何参数较为合理,并进行样机试验。样机试验证明:在额定工况下,泵的效率为68.86%,比国家标准值提高7.6%,达到设计要求。     

渐扩管内气液环状流附壁特性研究

利用Fluent软件模拟了油气两相流在渐扩管内的液相的附壁情况,得到了渐扩管扩张段的速度场和压力的分布规律,并分析了改变渐扩管的扩张角对扩张段环状流液膜附壁的影响。结果表明,渐扩管扩张段的锥角对环状流液膜的附壁有很大的影响,扩张段横截面的速度差值和压降随扩张角增大而增大,但是轴向梯度力却随之减小。这些结论对油气润滑系统中的输运有指导意义。     

Water consumption during solid state sodium borohydride hydrolysis

In this paper nickel acetate catalyzed sodium borohydride cartridges have been prepared and hydrolyzed with water for hydrogen production. Two technological solutions have been tested to increase the overall hydrogen yield, namely a porous water diffuser and a hydrophobic membrane. The first was used to improve water diffusion inside the hydride while the second to confine water inside the cartridge. The generated hydrogen flow showed a very reproducible behavior. Hydrogen promptly evolved just after water was pumped into the cartridge. After some initial peaks, a constant hydrogen flow has been recorded for the whole reaction time. The constant flow was related to the presence of the porous diffuser. The use of a hydrophobic membrane to confine the water inside the cartridge allowed to increase the overall hydrogen yield: about 6 water molecules per mol of hydride were required to complete the reaction. The reaction product was identified by XRD as Na₂B₂O₄*8H₂O. The cartridge hydrogen gravimetric content, based on water and sodium borohydride weight, was as high as 4.64%.     

A Real-coded Genetic Algorithm Applied to Optimum Design of a Low Solidity Vaned Diffuser for Diffuser Pinup

InboductionThe requirements for high efficiency and high headhave led to a widesPread use of vaned diffuser in diffeserPumP. Usually the kinetic eneny of the flow leaving theimPeller of a diffeser PUm stage is equlvalent toWtimately 20% to 40% of the total work inPu underthe tyPical operatin conditions. If an efficient diffoserpumP is to be designed, much Of thes kinehc eneTgy mustbe recovered efficienhy The vaned thser can convertboetic energy into a static pressure rise. HoweVer thecon…     

钯合金扩散室微束等离子焊接

针对钯合金扩散室的结构及焊接特点，研究了钯膜与不锈钢的微束等离子焊接工艺，通过设计合理的夹具及在钯膜表面镀镍的方法得到了气密性优良的焊接件。产品的漏率小于1×10^-9 Pa.m³/s，满足扩散室低泄漏率的使用要求。     

横流中扩散器长度对浮力射流的影响

本文利用混合有限分析法及交错网格的思想，对横流中有限长线源型浮力射流进行数值计算，成功模拟了端涡现象及其发展过程，并分析了扩散器长度对湍浮力射流的影响。     

An investigation of air inlet types in mixing ventilation

Previous studies have shown that dispersion of contaminant concentrations strongly depends on air inlet types. However, these studies were performed computationally, not experimentally. Thus, the purpose of the current research is to obtain contaminant concentrations in a room, to perform qualitative and quantitative comparison for a wall jet (WJ) air inlet and a ceiling diffuser (CD) air inlet, and to determine more efficient inlet and outlet configuration.     

低稠度半高叶片扩压器的模型级性能研究

通过数值模拟的方法研究了低稠度半高叶片扩压器在大流量离心压缩机模型级中的应用,并比较了其与无叶扩压器对模型级气动性能影响的差异.研究结果表明:采用低稠度半高叶片扩压器的模型级基本消除了盖侧附近低总压高熵值的区域,气动性能有较大提高.     

一种高温离心式压缩机扩压器的改进与优化

分析对比了无叶扩压器和叶片扩压器的特性,探讨了一种高温离心式压缩机中采用低稠度叶片扩压器替代无叶扩压器的设计方案,并通过压缩机的性能测试验证了该方案的可行性。