某乏燃料运输容器减震器设计及验证

目的 研发用于某运输容器的减震器,同时探究减震器尺寸和填充材料的分散性对减震器设计的影响。方法 开展减震器尺寸对运输容器减震效果的分析计算,通过木材抗压强度试验获取木材压缩强度分散性,并使用有限元方法对运输容器进行9 m过重心角跌落分析,并进行9 m过重心角跌落测试验证。结果 一般来说减震器尺寸越大,其吸收能量越多,但其尺寸超过某临界点后减震效果反而下降;低抗压强度的填充木材吸能力不如较高抗压强度的,但填充木材抗压强度较大时,减震器偏硬会导致较大的容器刚体加速度。结论 该减震器设计合理,满足规范要求。填充木材的力学性能分散性,偏大或偏小都会对设计产生影响,因此,使用木材作为缓冲填充材料,设计时需要充分考虑木材压缩强度分散性对缓冲效果的影响。     

超材料吸波体吸波特性研究

设计了一个强谐振超材料吸波体,它由电谐环振器(Electric ring resonator)和短导线组合而成.采用数值仿真法,在8～12GHz波段提取了这种超材料的s参数,并计算了其吸渡率.单层超材料吸波体在10.2GHz处达到吸收峰,吸波率达91.3%.多层组合吸渡体在9.72GHz处峰值吸波率接近100%.与传统吸波材料不同的是,该超材料吸波体完全由金属结构组成,通过对介电常数和磁导率的灵活调节,经优化设计即可实现对入射电磁波的高吸收.另外,通过尺寸变化的多层组合结构,利用不同吸波频段的叠加效应,实现了对吸波频带的拓宽.     

主动控制在减振器中的机械实现

在不改变夏利车其它结构的基础上,本文应用半主动隔振原理,对其油液减振器的最主要部件——活塞件进行了改进,使阻尼器节流孔的大小随路面起伏而自动调整,产生随车架垂向速度变化的阻尼力.经试制验证,改进后的减振器的性能和寿命都得到了很大提高.     

快中子堆用碳化硼材料的成分和性能设计

快中子堆在最终解决世界能源问题中占有十分重要的地位,碳化硼是快中子堆国际普遍接受的中子吸收材料,作者综述了快堆对材料的要求以及碳化硼的优点和限制,评述了碳化硼芯块密度、硼碳比、晶粒度、热传导率、杂质铁含量等对作为寿命限制参数的氦释放率和肿胀率的影响,提出了材料设计的观点。     

电磁波吸收材料的研制及发展动向

本文概要地阐述了电磁波吸收材料的用途作用机理、产品及今后的发展动向,并对国内外广家及其产品做了简介.     

Development Of An Air Cleaner Based On Gas Absorption Membranes

The aim of the present study is to demonstrate the technical feasibility of the membrane absorber as an air cleaner with small-scale modules. Six small-scale membrane modules with different fibre lengths and fibre diameters have been investigated. Each module has been tested as a membrane absorber treating air with 4 different chemicals, formaldehyde, nitrogen dioxide, ammonia and acetone, with tap water. The pressure drop and the filtration efficiency has been measured at different flow rates. From these results the optimal membrane module has been selected for the following reasons: low pressure drop, small required membrane surface area and high filtration efficiency. The experiments were continued with the selected module for ETS in a test room. Water soluble compounds were removed with an efficiency of at least 95%. The efficiency was inconsistent for NO, (not expected) and low for hydrocarbons (as expected). The sensory filtration efficiency was also measured with two different methods, the threshold method and the decipol method. Both efficiencies were about 50%. Recommendations for future research are given.     

Measured and predicted effect of flowrate and tube spacing on horizontal tube absorber performance

The presented model applies to absorption in a falling film of constant thickness of a binary mixture with only one component in the vapour phase. The mathematical formulation with partial differential equations is based on very general assumptions. The model is validated for a horizontal tube absorber. The absorber is simplified to a series of vertical falling films with mixing conditions in between. The dimensionless absorber operating conditions are: Gz = 0.1–10, Le = 0.002 or 0.004, Λ = 0.01 or 0.02, Bi ≈ 5, θ_c ≈ −0.2, N_c = 0.1. The absorber consists of 10 cooled tubes, measurements were obtained at tube spacings: 0, 3, 15 and 24 mm and with sheet, droplet and jet flow in between the tubes. The correlation between predicted and measured absorption outcomes is very strong. On average the predicted outcomes equal the measured ones within the scatter, if the diffusivity is taken 0.3 times the established correlation and varies with x and y.     

Study on the shock absorbing technique of high speed railway bridges

Based on the idea of “bearing function separation ”, a structural member called shock absorber that makes use of its plastic deformation, is presented for reducing the seismic response of the bridge. The design criterion, for matching material stress, strain and earthquake fortification aim, is also given. The analysis results show that the high speed railway box girder with the absorber in this paper has great reduction of seismic response of the bridge piers.     

一种并行多通道数据获取系统设计

针对无损检测技术中激振检振技术对相位信息应用的Z-程需求‘,基于MAXl308设计了一种8通道并行数据获取系统,数据完整地保持了各通道间的相位信息。并根据工程需求设计了调理电路,系统可以完成电压士5V之间的信号采样,每通道的采样速率达到456ks／s。