Development of mobile miniature natural gas liquefiers

With increasing consumption of natural gas (NG), small NG reservoirs, such as coalbed methane and oil field associated gas, have recently drawn significant attention. Owing to their special characteristics (e.g., scattered distribution and small output), small-scale NG liquefiers are highly required. Similarly, the mixed refrigerant cycle (MRC) is suitable for small-scale liquefaction systems due to its moderate complexity and power consumption. In consideration of the above, this paper reviews the development of mobile miniature NG liquefiers in Technical Institute of Physics and Chemistry (TIPC), China. To effectively liquefy the scattered NG and overcome the drawbacks of existing technologies, three main improvements, i.e., low-pressure MRC process driven by oil-lubricated screw compressor, compact cold box with the new designed heat exchangers, and standardized equipment manufacturing and integrated process technology have been made. The development pattern of “rapid cluster application and flexible liquefaction center” has been eventually proposed. The small-scale NG liquefier developed by TIPC has reached a minimum liquefaction power consumption of about 0.35 kW·h/Nm³. It is suitable to exploit small remote gas reserves which can also be used in boil-off gas reliquefaction and distributed peak-shaving of pipe networks.     

二氧化碳跨临界系统参数间相互关系的热力学第二定律的分析与研究

本文利用热力学第二定律（Yong） 的(exergy)分析法，对二氧化碳跨临界制冷循环系统进行了仿真和分析，分析显示：炯效率随着放热压力的变化而变化，其最大值出现在最优放热压力处，同时，本文还就气体冷却器口温度、蒸发温度及蒸汽过热度对系统Yong效率的影响进行了仿真和分析。     

热管传热性能对小型热管换热器散热效能影响

在零重力辅助下,小热管热阻是小型热管换热器散热效能的重要影响因素之一。基于集总参数法对于换热器系统数值计算的高效性思想,建立了热管、热管换热器的集总参数模型。对同一热管换热器选用不同传热性能的热管,在不同传热温差和流体质量流速下,就其散热效能进行了数值计算。计算结果表明,在零重力辅助下,热管换热器管内热阻存在一临界值Rcri。当热阻RHP≤Rcri时,管外热阻起主导作用,热管换热器的散热效能εh几乎不随热管管内热阻的值而变化。     

微型生化分析仪样品室温度控制系统研究

结合微型生化分析仪样品室的要求,设计了一种基于单片机的微型生化分析仪样品室温度控制系统.它以AT89S51为核心,采用单总线高精度数字温度传感器DS18B20对样品室温度采样,同时利用汇编语言编写温度设定与控制程序,采用半导体制冷的方式,实现了温度在25℃、30℃、32℃和37℃四个温度值的稳定,控制精度达±0.5℃.     

Low-cycle fatigue properties of eutectic solders at high temperatures

This paper details the deformation mechanism and low‐cycle fatigue life of eutectic solder alloys at high temperature (around 0.8T_m). Grain boundary sliding generally nucleates a wedge‐type cavity that reduces the low‐cycle fatigue life of metals. In this study, grain boundary sliding has promoted intergranular failure contributing to the reduction in fatigue life of Sn–Ag–Cu alloy. However, grain boundary sliding has exerted no deleterious effects on fatigue resistance of eutectic Pb–Sn and Bi–Sn alloys. The phase boundary sliding with very fine microstructure induces exceptional ductility in these alloys leading to superior low‐cycle fatigue endurance for theses eutectic Pb–Sn and Bi–Sn alloys.     

提高超小型铝电解电容器生产一次合格率

恰当选择原材料、确保铆接工序质量、重视工作电解液的配比、严控各工序成品率是提高超小型铝电解电容器投入产出一次合格率的关键。以１０Ｖ－４７μＦ（４ｍｍ×７ｍｍ）产品为例，投入产出一次合格率达９４％以上。     

蒙特卡罗方法在空间辐射制冷器理论分析及热设计计算中的应用

介绍了二级抛物面型辐射制冷器的热物理模型及用蒙特卡罗方法数值模拟解决其热流理论和辐射热耦合表面（漫发射、镜反射）辐射热交换的处理方法。     

煤气压缩机存在问题及改造措施

对煤气压缩机运行以来所存在的问题进行了分析，相继采取的改造措施及取得的效果作了探讨。重点阐述了油冷却器的改造。     

武钢 10000 m3/h制氧机主冷泄漏故障处理及应急保产方式

氧气生产单位保用户用气一旦出现较为紧张的局面时，如何正确处理保安全生产运行、保用户生产、安排抢修时间三者之间的关系，值得关注与研究。