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101.
针对某车型悬架减振器异响问题,分别进行整车道路及台架试验,获得两者的一致性规律,即减振器活塞杆加速度信号在特定频段内具有相似性。进而对减振器异响台架试验的辨识方法进行研究,提出时域峰谷差值法、分段功率谱RMS值法及基于特征能量小波分析法,并分析比较其优缺点。在此基础上提出并采用基于权重系数的聚类分析法,将单指标刚性矩形判定区域转化为多指标柔性圆形判定区域,减少评判结果因单指标误判导致最终结果误判的概率,可为大批量、不同型号减振器异响辨识及提高鉴别准确度提供参考。 相似文献
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J. Sumner N. J. Simms W. Stamm J. E. Oakey 《Energy Materials: Materials Science and Engineering for Energy Systems》2016,11(4):1090-1099
Integrated gasification combined cycles can incorporate pre-combustion carbon capture. High-H2 syngas produces high H2O levels after combustion, potentially accelerating gas turbine component damage. Determining materials systems’ suitability for this novel environment requires exposures in representative environments. Thus, an existing 0.7?MW burner rig was modified to generate the combustion environment and incorporate a cascade of 15 air-cooled turbine blades. Computational fluid dynamic calculations using blade dimensions and flow requirements supported the cascade design and determined blade placement within the gas flow. Trials of the modified unit have shown that a simulated combusted H2-rich syngas composition was generated at gas temperatures ≤1440°C. A 1000?h exposure has been carried out with thermal barrier coated blades to demonstrate the operation of the unit.This paper is part of a thematic issue on the 9th International Charles Parsons Turbine and Generator Conference. All papers have been revised and extended before publication in Materials Science and Technology. 相似文献
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David Scott Zine Aidoun Mohamed Ouzzane 《International Journal of Refrigeration》2011,34(7):1717-1723
Supersonic ejectors have been used in cooling/refrigeration applications since the early 1900s. Interest in supersonic ejectors has been rekindled by recent efforts to reduce energy consumption; ejector refrigeration systems can be powered by solar energy or by waste heat generated by another process. This paper describes an experimental test bench using R245fa that was assembled and operated at CanmetENERGY in Varennes. The results from this test bench provide a source of reference data that may be used to validate numerical models of ejectors that could be used in refrigeration applications. Limited results from two numerical models are presented for comparison; global results from a 1D model and results from a detailed CFD model that show the flow field inside the ejector. 相似文献
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4000m低温车载钻机固控系统的研制 总被引:3,自引:2,他引:1
低温车载钻机固控系统在设计和制作方面的关键技术是保证所有部件能够在-45~50℃正常工作,车载固控系统的关键技术是车载罐体结构设计和固控系统流程设计。为此,对固控系统的容积和结构、钻井液罐体的结构、工艺流程、保暖和供暖系统进行设计,并确定了低温材料的选择方法。现场应用表明,环境温度为-45℃时,固控区保温棚内部温度不低于10℃;在风力达7级的恶劣天气和大雪天,保温棚的结构可靠,密封严密,可确保钻井正常进行;牵引车的运行速度为60 km/h,刹车灵敏、可靠,能将罐体顺利地拖往新井位,完全满足快速移运要求。 相似文献
108.
增压器和中冷器联合性能试验台 总被引:1,自引:0,他引:1
增压器和中冷器是柴油机增压系统的重要部件 ,其性能的优劣直接影响柴油机的经济性、动力性及可靠性。目前 ,我国机务部门已经实现了增压器的集中修理 ,并有完备的性能试验设备 ,但对中冷器的性能试验还缺乏必要的设备 ,这使装车运用的中冷器质量难以得到保证。为此 ,提出了建造增压器、中冷器联合试验台方案 ,它具有投资少 ,试验费用低 ,维修保养方便等优点。 相似文献
109.
Amadou D. Diop Emil Ceanga Jean-Louis Rtiveau Jean-Franois Mthot Adrian Ilinca 《Renewable Energy》2007,32(13):2268-2290
This paper deals with the methods of three-dimensional fixed-point wind speed real-time simulation modelled in large band, in order to use them in test rigs for experimental investigation of the wind energy conversion systems. The medium- and long-term components of the non-stationary wind speed are considered as known, being issued from measured data or by adopting a generic model. The spectral characteristics of three-dimensional turbulence are described either by the Kaimal or the von Karman models. The turbulence intensity and the length scale that take part in these models are calculated by the site parameters, using current standards. The basic idea of the methods for large-band three-dimensional wind simulation is to use rational shaping filters that approximate non-integer orders shaping filters issued from the Kaimal and the von Karman models. All the synthesized rational shaping filters use one time constant, automatically adapted to the medium- and long-term components that pilot the other time constants of the shaping filters by a set of parameters practically constant. Some numerical results concerning time series that simulate the non-stationary wind speed with three-dimensional turbulence components based on Kaimal and von Karman models are presented. 相似文献
110.