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143.
圆形料管变锥面翻领成型器的研究 总被引:1,自引:0,他引:1
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。 相似文献
144.
Weiwei Cai Liang Yan Liang Liang Wei Xing Changpeng Liu 《American Institute of Chemical Engineers》2013,59(3):780-786
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 相似文献
145.
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。 相似文献
146.
Preparation of water management layer and effects of its composition on performance of PEMFCs 总被引:1,自引:0,他引:1
Tian Jian-hua Shi Zhao-yuan Shi Jin-song Shan Zhong-qiang 《Energy Conversion and Management》2008,49(6):1500-1505
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. 相似文献
147.
Seok Cho Chul-Hwa Song Choon-Kyong Park Hwan-Yeol Kim Won-Pil Baek 《Nuclear Engineering and Design》2008,238(7):1525-1534
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. 相似文献
148.
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。 相似文献
149.
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。 相似文献
150.
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 总被引:1,自引:0,他引:1
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。 相似文献