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排序方式: 共有151条查询结果,搜索用时 15 毫秒
1.
基于生物免疫系统抗原与抗体互识别的结合能量模型,结合矩阵的奇异值分解,研究了适于三缸往复泵泵阀故障诊断的新方法.通过对三缸往复泵泵阀实际故障的诊断分析,表明基于结合能量的故障诊断方法具有较强的容错性和鲁棒性,并具有可视化及可解释性好等特点。 相似文献
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To overcome the limitations of traditional monitoring methods, based on vibration parameter image of rotating machinery, this paper presents an abnormality online monitoring method suitable for rotating machinery using the negative selection mechanism of biology immune system. This method uses techniques of biology clone and learning mechanism to improve the negative selection algorithm to generate detectors possessing different monitoring radius, covers the abnormality space effectively, and avoids such problems as the low efficiency of generating detectors, etc. The result of an example applying the presented monitoring method shows that this method can solve the difficulty of obtaining fault samples preferably and extract the turbine state character effectively, it also can detect abnormality by causing various fault of the turbine and obtain the degree of abnormality accurately. The exact monitoring precision of abnormality indicates that this method is feasible and has better on-line quality, accuracy and robustness. 相似文献
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In order to investigate the flow-induced vibration in the shroud passage of centrifugal pump and predict rotordynamic forces of centrifugal pump rotor system,an analysis of rotordynamic forces arising from shrouded centrifugal pump is presented. CFD techniques were utilized to analyze the full three-dimensional viscous,primary/secondary flow field in a centrifugal pump impeller to determine rotordynamic forces. Multiple quasi-steady solutions of an eccentric three-dimensional model at different whirl frequency ratios yielded the rotordynamic forces. The skew-symmetric stiffness,damping,and mass matrices were obtained by second-order least-squares analysis. Simulation of the coupled primary/secondary flow field was conducted,and the complex flow characteristics in the flow field of a shroud passage were achieved including the mean velocity and pressure,as well as the eddy in a large scale of flow field due to viscosity. The rotordynamic force coefficients were calculated,and the results were in good agreement with those of experiment except for the direct inertial coefficient without the consideration of whirling forces from the impeller primary flow passage. 相似文献
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可倾瓦轴承瓦块摆动特性 总被引:3,自引:0,他引:3
研究可倾瓦轴承瓦块摆动几何关系,基于分离变量法建立了有限长轴承油膜压力模型及瓦块力矩平衡方程,获得瓦块摆角与轴承参数之间的函数关系;以瓦块包角为80°、支点偏移量为0.5的四瓦块可倾瓦轴承为研究对象,计算分析其瓦块的摆动特性.理论推导表明,瓦块静平衡摆角只与瓦块结构参数、轴颈相对瓦块偏心率、间隙比有关,而与轴颈转速、油... 相似文献
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This paper implemented cooling configuration design on certain gas turbine HP rotor using parameterized method.It is convenient for complicated gas turbine blade modeling using parameters and also benefit for the geometry modify in later period.Parameterized modeling is the foundation of air cooling turbine blade design method engineering application.Mesh quality can be awarded when generated complicated cooling configuration blade grids,and also the increase of calculation error can arise by many mesh blocks.Film cooling and serpentine passage can effectively enhance the cooling effectiveness and protect blade. 相似文献
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To study the dynamic characteristics and damping mechanism of impact-contact between the tips of blades further more,the impact-contact between the tips of a pair of blades was studied through numerical simulation.In this paper,the dynamic equation of contact-impact between the tips was established and Newmark direct integration method was adopted in numerical simulation.The nonlinear response characteristics and damping mechanism of impact-contact system are obtained.The results of numerical simulation were obtained as follows:As the clearance between blade shrouds is smaller,the vibration amplitude is smaller.The clearance between blade shrouds has a great influence on the input energy of the aerodynamic-excitation-vibration force.As the clearance of blade shrouds increases,the input energy of the aerodynamic-excitation-vibration force increases rapidly. 相似文献
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旋转机械振动参数图形边缘纹理提取的数学形态学方法 总被引:1,自引:0,他引:1
针对旋转机械振动多维图形信息一直没有得到充分利用,在一定程度上影响诊断技术的推广和利用的问题,研究了直接提取和挖掘旋转机械振动状态参数图形特征信息的方法,提出了基于数学形态学的旋转机械振动参数图形特征提取方法.采用形态开-闭和闭-开级联组合的数学形态学滤波器实现振动参数图形滤波方法,研究了不同形态边缘检测算子,针对旋转机械振动参数图形探讨了经典的LOG边缘检测算子与基于形态学梯度的边缘纹理特征提取方法的应用效果.在600MW模化汽轮机转子试验台上进行了转子正常、转子不平衡故障、转子不对中故障、汽流激振及轴承松动故障的试验,分析结果表明可以准确地提取图形特征,为旋转机械故障诊断探索了一条新路. 相似文献