搜零法在相控阵雷达罩电性能测试中的应用

在机载相控阵雷达罩电性能测试过程中,由于被测天线是相控阵天线,使得测试方法与经典测试方法有所不同.文中对搜零法在相控阵雷达罩电性能测试中的应用进行了探索,确定了搜零系统中相控阵天线的安装方式和收发电轴对准的判据,集成了一套相控阵雷达罩电性能搜零系统,系统功能和精度满足测试需求.还在X波段相控阵雷达罩电性能测试中验证了搜零法的有效性,测试数据规律正确且重复性良好.测试结果表明相控阵雷达罩电性能搜零系统可用于新型战斗机雷达罩研制过程.     

对于1m管式间接蒸发冷却器冷却效果测试与分析

简述了管式间接蒸发冷却器的原理结构,并对管式间接蒸发冷却器的换热管管长设置为1 m,在不同二次/一次风量比的条件下对风量、温度、相对湿度、温降参数等进行实验测试,与1.5 m管式间接蒸发冷却器进行测试对比.测试结果表明,1 m管式间接蒸发冷却器二次/一次空气风量比为0.75时,湿球效率较高为55.6％.对影响降温效果的因素进行简要的分析,与1.5 m管式间接蒸发冷却器进行对比分析,提出在条件允许的前提下优先采用1.5 m管式间接蒸发冷却器.     

圆形料管变锥面翻领成型器的研究

通过对简单变锥面翻领成型器模型的研究,引入变锥面翻领成型器数学模型思想,并对其领口交接曲线、肩曲面、边界曲线的通式进行推导,在计算机上对所建模型进行了Pro/E三维仿真验证,为变锥面翻领成型器的后续研究奠定了理论基础。     

Model‐based design and optimization of the microscale mass transfer structure in the anode catalyst layer for direct methanol fuel cell

Microscale mass transfer structure in the anode catalyst layer (CL) can significantly alter the performance of a direct methanol fuel cell (DMFC) because it changes both the oxidation rate and crossover flux of methanol. The microscale mass transfer structure can be modified by changing the loading of the pore former (PF). An empirical model was developed for the microstructural design and optimization of anode CL by incorporating the PF into the anode CL. The optimal loading of PF is 100 g/m² according to the calculated results. Experimental results confirmed the accuracy of the calculations, and the passive DMFC performs 37% better by incorporating the optimal loading of PF into the anode CL as compared to the conventional anode CL. The validity of the proposed empirical model can also be proven by comparing the calculated polarization results with the previously reported experimental data. © 2012 American Institute of Chemical Engineers AIChE J, 59: 780–786, 2013     

蒸发冷却与半导体制冷相结合分体式蒸发空调器的试验研究

设计制作了蒸发冷却与半导体制冷相结合分体式蒸发空调器的试验样机,在标准的空调焓差检测实验台上,模拟室内外侧空气温湿度,在室外侧干球温度34℃,湿球温度18²3℃之间的工况下,对该分体式蒸发空调器的冷水的温度、流量,冷风的温湿度进行了试验。结果表明,该分体式蒸发空调器在室外工况湿球温度20℃以下不开启半导体制冷装置即可满足需要;配合4组半导体制冷装置即可满足室外工况湿球温度23℃时需要,同时也保证了半导体制冷装置较高的能效比;得出了该分体式蒸发空调器的最佳气水比为2,亚湿球效率为110%。进而为分体式蒸发空调器的优化设计与产品开发奠定基础。     

Preparation of water management layer and effects of its composition on performance of PEMFCs

A membrane electrode assembly (MEA) with a novel water management layer (WML) used in proton exchange membrane fuel cell (PEMFC) was prepared. The so called WML, which was located between the carbon paper and the catalyst layer, was a sublayer composed of carbon and hydrophobic PTFE. Various parameters of the WML, including carbon loading, PTFE content and species, sintering time and temperature and pore formers, were investigated in this study. As demonstrated in our experimental results, the performance of the membrane electrode assembly (MEA) PEMFC could be significantly improved by WML in the condition of operation with dry reactive gases. The MEA with the WML exhibited more stable performance than the situation of MEA without WML during a long time running period.     

Air clearing pressure oscillation produced in a quenching tank by a prototype unit cell sparger of the APR1400

KAERI has performed a series of experiments to investigate the performance of a prototype sparger for the APR1400 in view of a dynamic load oscillation with a variation of the test conditions such as a discharged air mass, a submergence of the sparger, the valve opening time, and the pool temperature during an air clearing phase. The air mass and pool temperature are in the range of 0.8–1.5 kg and 20–90 °C, respectively. The valve opening time can be adjusted within the range of 0.6–1.8 s. The maximum positive pressure amplitude, which is observed at the bottom of the quenching tank, is increased with the maximum header pressure of the sparger. The valve opening time has a considerable effect on the maximum amplitude. As the opening time decreases, the maximum amplitude at the tank wall is increased. Air mass and pool temperature, however, have a weak effect on the maximum amplitude. Oscillation frequency is decreased with an increase of the air mass in the range of 2.5–4.5 Hz.     

日本JGC公司B块轻烃分离装置转产改造研究

介绍一种改造日本JGC公司成套气体处理装置（简称B块）,进行轻烃深加工的工艺,实践证明,该工艺切实可行,使用较少投资,就可获得可观的经济效益。     

提高煤气灶具燃烧效率的探讨与研究

两段炉煤气热值低,迫切要求提高煤气灶具燃烧效率。从提高灶前压力和扩大喷嘴口径两方面计算和分析,得出相应解决办法。     

南水北调东线灯泡贯流泵水力模型及装置研究开发与应用

根据南水北调东线一期工程灯泡贯流泵站设计和建设需要,以南水北调金湖泵站设计工况为基础,自主研制开发贯流泵水力模型装置,利用FLUENT软件进行了CFD流场计算分析和设计优化。通过天津同台测试和专家鉴定,研制开发的两套水力模型装置最优工况点效率分别达到79.4%和81.9%,空化比转速达到1100以上。装置模型综合性能良好,运行范围宽,适用于1.0～4.5m的特低扬程泵站,在3m扬程下和相同性能的立式轴流泵相比,效率约提高5%,流量提高10%以上。同时,在水泵模型设计和装置性能优化方法上有所创新。