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271.
汽轮发电机的异常振动是发电厂最为常见故障。分析由于汽轮发电机转子不对称及热效应导致汽轮发电机产生振动的原因,并对发电机转子工作异常现象进行分析。最后,结合工程实例对某电厂大修后开机过程中异常振动故障进行分析,为发电机工频振动诊断提供分析判断的思路和方法。 相似文献
272.
分析研究了国内外几种港口工程规范中关于船舶风荷载计算的方法特点并应用同一算例进行了计算结果间的对比分析,评价了O ptim oor软件的可用性。 相似文献
273.
张榴晨 《变流技术与电力牵引》2006,(2):57-62
介绍了绿色能源的概念,以风力发电为重点介绍了电力电子技术在绿色能源发展中的应用以及分布式发电在绿色能源系统方面的应用. 相似文献
274.
以香日德-花石峡高原项目区土壤侵蚀现状为例,结合3种土壤侵蚀的特点,按照水土保持技术规范,提出分区、分类的高原公路水土流失预测方法,并详细分析预测结果,提出相应的监测和治理建议. 相似文献
275.
This paper presents experimental assessment of crack growth rates of S355J2+N steel in a corrosion fatigue environment similar to what is experienced on offshore wind farm monopile structures under various cyclic load frequencies in order to assess the effect of cyclic frequency of the applied loading within a frequency range pertinent to the structure. Fatigue crack propagation behaviour in this test programme is evaluated through fatigue tests on six compact tension test specimens in air and in laboratory simulated seawater under free corrosion condition. Fatigue crack lengths were monitored by back face strain (BFS), DCPD and ACPD. A regression model was derived through the BFS method to express strain values as a function of crack length to width ratio. The effectiveness of BFS method is particularly demonstrated in the simulated marine environment. Within the range of test frequencies, crack growth rates in simulated seawater when compared to the equivalent air test revealed environmental reduction factors of 2 and 4 at lower and higher values of stress intensity factors respectively. Significant difference in the results of the seawater test frequencies is discussed. 相似文献
276.
In this study corrosion-fatigue tests have been conducted on fracture mechanics specimens extracted from an S355 G10+M structural steel welded plate. The tests have been performed on compact tension specimens with the crack tip located in the heat affected zone. The corrosion-fatigue test results from this study have been compared with the data available on the base metal as well as air tests on the same material. Moreover, the obtained results have been compared with the corrosion-fatigue data available in the literature on a wide range of steels and also the fatigue trends for welded joints in free-corrosion condition recommended in the BS7910 Standard. The effect of the specimen orientation, with respect to the weld region, is also examined in this study and it has been found that higher corrosion-fatigue crack growth rates are generally observed in the tests with 0° orientation. The results have also shown that the corrosive environment has significant effects on the fatigue crack growth acceleration at the beginning of the tests; however, as the crack propagates, the environmental damage effect on crack growth behaviour becomes less pronounced. The results presented in this study are discussed in terms of improvement in the structural integrity assessment of offshore wind turbine monopiles. 相似文献
277.
采用模块化,变比热的方法在labview平台上建立了燃气轮机动态模型,结合电机扭矩控制实现了燃气轮机特性的模拟。设计了燃燃联合运行负荷平均分配的控制策略,并进行了燃燃联合动力共同带负载的半物理仿真试验,试验结果证实采用本文设计的控制策略能实现负荷平均分配,动态过程比较稳定,设计的控制策略能基本满足要求。 相似文献
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