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为了解决长管拖车气瓶瓶体内部缺陷快速无损检测的难题,利用超声导波技术对长管拖车气瓶试块进行检测。结果显示:超声导波技术一次检测的距离沿波束方向可以达到1m,并且可以准确的发现不同大小的V形槽缺陷。缺陷的位置和长度大小可以准确的测量,并且和实际测量值取得了良好的符合。试验结果很好地证明了超声导波技术的快速准确的优点,对实际现场检测具有指导意义。 相似文献
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本文介绍气门密封面作用长度快速检测装置,适用于发动机中进排气门的生产现场检测。文章阐述了检具的工作原理和结构特点,并就检测结果作了误差分析,表明其测量精度完全能满足需要。 相似文献
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图像处理技术在零件表面破损检测中的应用 总被引:3,自引:0,他引:3
阐述图像处理技术用于零件表面缺陷检测的原理,并以发动机中连杆大小头结合面的破口缺损为例。介绍了所研制专用检测设备的基本组成、设计特点和运行过程,显现了其在现场工作条件下实施快速测量的优越性。 相似文献
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为解决发动机气缸盖气门阀座底孔深度检测困难问题,对气门阀座底孔的技术要求进行详细分析,设计阀座深度测量方案及专用工具。测量工具由测量块、探针、螺钉、紧固套、千分表和标准块组成,以标准块U型槽的深度为基准,根据千分表指针的摆动距离计算阀座底孔深度。测量工具的测量系统分析(measurement system analysis, MSA)验证结果表明,量具的重复性和再现性符合要求,适用于阀座底孔深度的测量。该量具能快速准确地测量阀座底孔深度,结构简单紧凑,使用方便,满足生产线的检测效率和精度要求。 相似文献
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Methanol crossover is a serious problem in a direct methanol fuel cell (DMFC), which causes significant voltage loss and waste of fuel. Due to methanol crossover, most DMFCs must operate on a fuel with a very low methanol concentration; yet very low methanol concentration also causes a poor cell performance. Thus, it is very important to find the optimal operating conditions of methanol concentration and other operating parameters. In this research, methanol crossover rate in a DMFC is determined by measuring the carbon dioxide concentration at the cathode exit in real time. By measuring methanol crossover and cell performances at different inlet methanol concentrations and various operating conditions three types of characteristics are identified in the relationships between methanol crossover and cell current density. Further analysis of these relationships between methanol crossover and cell performances reveals the optimal methanol concentration and other operating parameters, at which the cell reaches optimal performance without incurring excessive methanol crossover. Furthermore, transient peaks of methanol crossover have been identified when the cell voltage suddenly changes. Analyses of these peaks show that they are caused by the hysteresis of methanol concentration at the interface between the anode catalyst layer and the membrane. 相似文献
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《International Journal of Hydrogen Energy》2022,47(93):39626-39638
In this study, a new procedure for optimum and effective system identification of Proton Exchange Membrane Fuel Cell (PEMFC) stacks is introduced. The present study proposes a method to obtain the optimum amount of the uncertain parameters of the PEMFC design to deliver the uppermost confirmation with the real output voltage value. To do so, the integral of the absolute error (IAE) between the real and model outputted voltage values is considered an objective function. To minimize this function, a modified design of the emperor penguin optimizer has been suggested. The method has been then investigated by performing two real case study models and its achievements are put in comparison with several latest techniques to show the method's productivity. The achievements show that the suggested technique has a higher ability for parameter estimation of the PEMFC models. 相似文献