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期刊论文 39

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2023 1

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关键词

倾转旋翼机；状态跟踪控制；线性切换系统；类时间依赖的多Lyapunov函数方法；光滑插值 1

光镊；光致旋转；角动量；微纳转子 1

动、静叶相互作用 1

单边直线感应电机 1

可压缩流 1

叶轮机 1

微角度检测；差分电容结构；转子式陀螺 1

扰动涡方法 1

数字信号处理器 1

数字控制 1

无轴承永磁同步电机 1

永磁同步发电机；径向通风孔；转矩脉动；分段斜极；磁体形状优化；有限元分析；风电 1

补偿 1

解耦 1

解耦控制 1

转子式陀螺；电磁驱动；快速启动；分时复用算法；闭环控制 1

转子磁场定向控制 1

轴向磁通电机；印制电路板；Halbach永磁体阵列；有限元法 1

边缘效应 1

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Impact analysis of compressor rotor blades of an aircraft engine

Y B SUDHIR SASTRY, B G KIROS, F HAILU, P R BUDARAPU

《结构与土木工程前沿（英文）》 2019年 第13卷 第3期   页码 505-514 doi: 10.1007/s11709-018-0493-3

摘要： Frequent failures due to foreign particle impacts are observed in compressor blades of the interceptor fighter MIG-23 aircraft engines in the Ethiopian air force, supplied by the Dejen Aviation Industry. In this paper, we made an attempt to identify the causes of failure and hence recommend the suitable materials to withstand the foreign particle impacts. Modal and stress analysis of one of the recently failed MIG-23 gas turbine compressor blades made up of the following Aluminum based alloys: 6061-T6, 7075-T6, and 2024-T4, has been performed, apart from the impact analysis of the rotor blades hit by a granite stone. The numerical results are correlated to the practical observations. Based on the modal, stress and impact analysis and the material properties of the three considered alloys, alloy 7075-T6 has been recommended as the blade material.

关键词： axial flow compressor     rotor and stator blades     aircraft engine     stress and impact analysis     aluminum alloys    

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Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 483-488 doi: 10.1007/s11465-007-0084-9

摘要： This paper presents an optimization model for rotor blades of horizontal axis wind turbines. The model refers to the wind speed distribution function on the specific wind site, with an objective to satisfy the maximum annual energy output. To speed up the search process and guarantee a global optimal result, the extended compact genetic algorithm (ECGA) is used to carry out the search process. Compared with the simple genetic algorithm, ECGA runs much faster and can get more accurate results with a much smaller population size and fewer function evaluations. Using the developed optimization program, blades of a 1.3 MW stall-regulated wind turbine are designed. Compared with the existing blades, the designed blades have obviously better aerodynamic performance.

关键词： population     extended     algorithm     developed optimization     accurate    

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A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

《能源前沿（英文）》 2016年 第10卷 第2期   页码 176-191 doi: 10.1007/s11708-015-0386-2

摘要： Today, induction machines are playing, thanks to their robustness, an important role in world industries. Although they are quite reliable, they have become the target of various types of defects. Thus, for a long time, many research laboratories have been focusing their works on the theme of diagnosis in order to find the most efficient technique to predict a fault in an early stage and to avoid an unplanned stopping in the chain of production and costs ensuing. In this paper, an approach called Park’s vector product approach (PVPA) was proposed which was endowed with a dominant sensitivity in the case in which there would be rotor or stator faults. To show its high sensitivity, it was compared with the classical methods such as motor current signature analysis (MCSA) and techniques studied in recent publications such as motor square current signature analysis (MSCSA), Park’s vector square modulus (PVSM) and Park-Hilbert (P-H) (PVSM ). The proposed technique was based on three main steps. First, the three-phase currents of the induction motor led to a Park’s vector. Secondly, the proposed PVPA was calculated to show the distinguishing spectral signatures of each default and specific frequencies. Finally, simulation and experimental results were presented to confirm the theoretical assumptions.

关键词： induction motor     incipient broken bar     extended Park’s vector approach     spectral analysis     inter-turn short-circuit     Hilbert transform    

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Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 384-398 doi: 10.1007/s11705-020-1928-7

摘要： The jet-flow high shear mixer (JF-HSM) is a new type of intensified equipment with special configurations of the rotor and the stator. The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters, such as rotor diameter, rotor blade inclination, rotor blade bending direction, stator diameter, and stator bottom opening diameter. The flow characteristics were examined by computational fluid dynamic simulations. Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening. With the increase in the shear head size and the change in the rotor into a backward-curved blade, the solid-liquid mass transfer rate can be remarkably increased under the same input power. Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.

关键词： jet-flow high shear mixer     solid particle dissolution     power consumption characteristics     CFD Simulation    

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用可压缩流涡方法模拟叶轮机动静叶的相互作用

陈矛章,彭波

《中国工程科学》 2000年 第2卷 第2期   页码 15-23

摘要：

本课题组发展了一种扰动涡方法，用以研究叶轮机内动、静叶相互作用[1，2]。其优点是物理图画清楚，计算收敛快。它采用了一个重要假设：扰动胀量为零，从而大大简化 了计算过程。文章的目的是研究此假设的影响，并取消此假设，使扰动涡方法建立在完全严格的数学基础上。由于取消了“扰动胀量为零的假设，需要耦合求解扰动质量方程、扰动涡量输运方程和扰动能量输运方程。这是文章与文献[1，2]的主要区别。

文献[1,2]对NASA67压气机第一级内由于动、静叶间的相互作用引起的非定常流动过程作了数值模拟，并与试验结果作了对比。文章也作了同样的算例，以研究扰动胀量为零的影响。数值模拟结果表明，在引入了扰动胀量后，用扰动涡方法模拟动静干涉仍保持较好的收敛性和收敛速度，且与试验的符合程度更好。文章强调指出，即使对于非定常可压流，为满足无渗透边界条件所需的运动分量也是用椭圆类的拉普拉斯方程描述，而不是用双曲类的方程描述。“扰动胀童为零”不能等同于扰动运动为不可压。

关键词： 叶轮机     动、静叶相互作用     扰动涡方法     非定常流     可压缩流    

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Condition monitoring of a wind turbine generator using a standalone wind turbine emulator

Himani,Ratna DAHIYA

《能源前沿（英文）》 2016年 第10卷 第3期   页码 286-297 doi: 10.1007/s11708-016-0419-5

摘要： The intend of this paper is to give a description of the realization of a low-cost wind turbine emulator(WTE) with open source technology from graze required for the condition monitoring to diagnose rotor and stator faults in a wind turbine generator (WTG). The WTE comprises of a 2.5 kW DC motor coupled with a 1 kW squirrel-cage induction machine. This paper provides a detailed overview of the hardware and software used along with the WTE control strategies such as MPPT and pitch control. The emulator reproduces dynamic characteristics both under step variations and arbitrary variation in the wind speed of a typical wind turbine (WT) of a wind energy conversion system (WECS). The usefulness of the setup has been benchmarked with previously verified WT test rigs made at the University of Manchester and Durham University in UK. Considering the fact that the rotor blades and electric subassemblies direct drive WTs are most susceptible to damage in practice, generator winding faults and rotor unbalance have been introduced and investigated using the terminal voltage and generated current. This wind turbine emulator (WTE) can be reconfigured or analyzed for condition monitoring without the need for real WTs.

关键词： condition monitoring (CM)     wind turbine emulator (WTE)     wind turbine generator (WTG)     maximum power point tracking (MPPT)     tip speed ratio (TSR)     rotor faults     stator faults    

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Two-sided ultrasonic surface rolling process of aeroengine blades based on on-machine noncontact measurement

Shulei YAO, Xian CAO, Shuang LIU, Kaiming ZHANG, Xiancheng ZHANG, Congyang GONG, Chengcheng ZHANG

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 240-255 doi: 10.1007/s11465-019-0581-7

摘要： As crucial parts of an aeroengine, blades are vulnerable to damage from long-term operation in harsh environments. The ultrasonic surface rolling process (USRP) is a novel surface treatment technique that can highly improve the mechanical behavior of blades. During secondary machining, the nominal blade model cannot be used for secondary machining path generation due to the deviation between the actual and nominal blades. The clamping error of the blade also affects the precision of secondary machining. This study presents a two-sided USRP (TS-USRP) machining for aeroengine blades on the basis of on-machine noncontact measurement. First, a TS-USRP machining system for blade is developed. Second, a 3D scanning system is used to obtain the point cloud of the blade, and a series of point cloud processing steps is performed. A local point cloud automatic extraction algorithm is introduced to extract the point cloud of the strengthened region of the blade. Then, the tool path is designed on the basis of the extracted point cloud. Finally, an experiment is conducted on an actual blade, with results showing that the proposed method is effective and efficient.

关键词： aeroengine blades     on-machine noncontact measurement     point cloud processing     path planning     surface strengthening    

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Novel casting processes for single-crystal turbine blades of superalloys

Dexin MA

《机械工程前沿（英文）》 2018年 第13卷 第1期   页码 3-16 doi: 10.1007/s11465-018-0475-0

摘要：

This paper presents a brief review of the current casting techniques for single-crystal (SC) blades, as well as an analysis of the solidification process in complex turbine blades. A series of novel casting methods based on the Bridgman process were presented to illustrate the development in the production of SC blades from superalloys. The grain continuator and the heat conductor techniques were developed to remove geometry-related grain defects. In these techniques, the heat barrier that hinders lateral SC growth from the blade airfoil into the extremities of the platform is minimized. The parallel heating and cooling system was developed to achieve symmetric thermal conditions for SC solidification in blade clusters, thus considerably decreasing the negative shadow effect and its related defects in the current Bridgman process. The dipping and heaving technique, in which thin-shell molds are utilized, was developed to enable the establishment of a high temperature gradient for SC growth and the freckle-free solidification of superalloy castings. Moreover, by applying the targeted cooling and heating technique, a novel concept for the three-dimensional and precise control of SC growth, a proper thermal arrangement may be dynamically established for the microscopic control of SC growth in the critical areas of large industrial gas turbine blades.

关键词： superalloy     investment casting     Bridgman process     directional solidification     single crystal     turbine blade    

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A novel NN based rotor flux MRAS to overcome low speed problems for rotor resistance estimation in vector

Venkadesan ARUNACHALAM,Himavathi SRINIVASAN,A. MUTHURAMALINGAM

《能源前沿（英文）》 2016年 第10卷 第4期   页码 382-392 doi: 10.1007/s11708-016-0421-y

摘要： This paper presents a new neural network based model reference adaptive system (MRAS) to solve low speed problems for estimating rotor resistance in vector control of induction motor (IM). The MRAS using rotor flux as the state variable with a two layer online trained neural network rotor flux estimator as the adaptive model (FLUX-MRAS) for rotor resistance estimation is popularly used in vector control. In this scheme, the reference model used is the flux estimator using voltage model equations. The voltage model encounters major drawbacks at low speeds, namely, integrator drift and stator resistance variation problems. These lead to a significant error in the estimation of rotor resistance at low speed. To address these problems, an offline trained NN with data incorporating stator resistance variation is proposed to estimate flux, and used instead of the voltage model. The offline trained NN, modeled using the cascade neural network, is used as a reference model instead of the voltage model to form a new scheme named as “NN-FLUX-MRAS.” The NN-FLUX-MRAS uses two neural networks, namely, offline trained NN as the reference model and online trained NN as the adaptive model. The performance of the novel NN-FLUX-MRAS is compared with the FLUX-MRAS for low speed problems in terms of integral square error (ISE), integral time square error (ITSE), integral absolute error (IAE) and integral time absolute error (ITAE). The proposed NN-FLUX-MRAS is shown to overcome the low speed problems in Matlab simulation.
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Timing decision-making method of engine blades for predecisional remanufacturing based on reliability

Le CHEN, Xianlin WANG, Hua ZHANG, Xugang ZHANG, Binbin DAN

《机械工程前沿（英文）》 2019年 第14卷 第4期   页码 412-421 doi: 10.1007/s11465-019-0551-0

摘要： A timing decision-making method for predecisional remanufacturing is presented. The method can effectively solve the uncertainty problem of remanufacturing blanks. From the perspective of reliability, this study analyzes the timing decision-making interval for predecisional remanufacturing of mechanical products during the service period and constructs an optimal timing model based on energy consumption and cost. The mapping relationships between time and energy consumption are predicted by using the characteristic values of performance degradation of products combined with the least squares support vector regression algorithm. Application of game theory reveals that when the energy consumption and cost are comprehensively optimal, this moment is the best time for predecisional remanufacturing. Used engine blades are utilized as an example to demonstrate the validity and effectiveness of the proposed method.

关键词： predecisional remanufacturing     reliability     least squares support vector regression (LS-SVR)     game theory    

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Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 203-213 doi: 10.1007/s11465-011-0131-4

摘要：

Crack on a shaft is one of the common damages in a rotor system. In this paper, transverse vibrations are calculated to compare the influences of transverse crack and slant crack on the rotor system. Results show that the vibration amplitude of the rotor system with a 45° slant crack on the shaft is larger than that with a transverse crack when the two types of crack have the same depth and the rotor system runs in the same condition. Stability and dynamic characteristics of the rotor system with a 45° slant crack on the shaft under torsional excitation are analyzed by considering opening and closing of the crack. It is shown that the instability of the transverse vibration of the rotor system increases with increasing difference between the bending stiffness in two main directions, and the vibration is stable when the two bending stiffness are identical. The spectrum analysis of the steady-state response reveals that the gravity and the eccentricity produce different frequency components, and when the two bending stiffness are identical, the multiple frequency components of the torsional excitation disappear. Further investigation shows that the vibration amplitudes in combined frequencies increase rapidly in transversal, torsional, and axial vibration with increasing slant crack depth. The results are helpful for the understanding the dynamic behavior of a rotor system with a slant crack on a shaft and can be used for the detection of the slant crack on a shaft.

关键词： rotor dynamics     slant crack     stability     torsional excitation     open and close    

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Study on wave rotor refrigerators

Yuqiang DAI, Dapeng HU, Meixia DING

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 83-87 doi: 10.1007/s11705-009-0075-y

摘要： As a novel generation of a rotational gas wave machine, the wave rotor refrigerator (WRR) is an unsteady flow device used for refrigeration, in whose passages pressured streams directly contact and exchange energy due to the movement of pressure waves. In this paper, the working mechanism and refrigeration principle are investigated based on the one-dimensional unsteady flow theory. A basic limitation on main structural parameters and operating parameters is deduced and the wave diagram of WRR to guide designing is sketched. The main influential factors are studied through an experiment. In the DUT Gas Wave Refrigeration Studying and Development Center (GWRSDC) lab, the isentropic efficiency can now reach about 65%. The results show that the WRR is a feasible and promising technology in pressured gas refrigeration cases.

关键词： wave rotor     refrigeration     unsteady flow theory     wave diagram    

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Application of high-turning bowed compressor stator to redesign of highly loaded fan stage

LI Shaobin, SU Jiexian, WANG Zhongqi

《能源前沿（英文）》 2008年 第2卷 第4期   页码 534-540 doi: 10.1007/s11708-008-0066-6

摘要： A redesign of a highly loaded fan stage by using high-turning bowed compressor stator was conducted. The original tandem stator was replaced by the highly loaded bowed stator which was applicable to highly subsonic flow conditions. 3D contouring technique and local modification of blade were applied to the design of the bowed blade in order to improve the aerodynamic performance and the matching of the rotor and stator blade rows. Performance curves at different rotating speeds and performances at different operating points for both the original fan stage and redesigned fan stage were obtained by numerical simulations. The results show that the highly loaded bowed stator can be used not only to improve the structure and the aerodynamic performances at various operating points of the compressor stage but also to provide high performances at off-design conditions. It is believed that the highly loaded bowed stator can advance the design of high-performance compressor.

关键词： off-design     different     numerical     contouring technique     high-performance compressor    

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The computational fluid dynamic modeling of downwash flow field for a six-rotor UAV

Yongjun ZHENG, Shenghui YANG, Xingxing LIU, Jie WANG, Tomas NORTON, Jian CHEN, Yu TAN

《农业科学与工程前沿（英文）》 2018年 第5卷 第2期   页码 159-167 doi: 10.15302/J-FASE-2018216

摘要： The downwash flow field of the multi-rotor unmanned aerial vehicle (UAV), formed by propellers during operation, has a significant influence on the deposition, drift and distribution of droplets as well as the spray width of the UAV for plant protection. To study the general characteristics of the distribution of the downwash airflow and simulate the static wind field of multi-rotor UAVs in hovering state, a 3D full-size physical model of JF01-10 six-rotor plant protection UAV was constructed using SolidWorks. The entire flow field surrounding the UAV and the rotation flow fields around the six rotors were established in UG software. The physical model and flow fields were meshed using unstructured tetrahedral elements in ANSYS software. Finally, the downwash flow field of UAV was simulated. With an increased hovering height, the ground effect was reduced and the minimum current velocity increased initially and then decreased. In addition, the spatial proportion of the turbulence occupied decreased. Furthermore, the appropriate operational hovering height for the JF01-10 is considered to be 3 m. These results can be applied to six-rotor plant protection UAVs employed in pesticide spraying and spray width detection.

关键词： CFD simulation     downwash flow field     numerical analysis     plant protection     six-rotor UAV    

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Structure improvement and strength finite element analysis of VHP welded rotor of 700°C USC steam turbine

Jinyuan SHI,Zhicheng DENG,Yong WANG,Yu YANG

《能源前沿（英文）》 2016年 第10卷 第1期   页码 88-104 doi: 10.1007/s11708-015-0387-1

摘要： The optimized structure strength design and finite element analysis method for very high pressure (VHP) rotors of the 700°C ultra-super-critical (USC) steam turbine are presented. The main parameters of steam and the steam thermal parameters of blade stages of VHP welded rotors as well as the start and shutdown curves of the steam turbine are determined. The structure design feature, the mechanical models and the typical position of stress analysis of the VHP welded rotors are introduced. The steady and transient finite element analysis are implemented for steady condition, start and shutdown process, including steady rated condition, 110% rated speed, 120% rated speed, cold start, warm start, hot start, very hot start, sliding-pressure shutdown, normal shutdown and emergency shutdown, to obtain the temperature and stress distribution as well as the stress ratio of the welded rotor. The strength design criteria and strength analysis results of the welded rotor are given. The results show that the strength design of improved structure of the VHP welded rotor of the 700°C USC steam turbine is safe at the steady condition and during the transient start or shutdown process.

关键词： 700°C ultra-super-critical unit     steam turbine     very high pressure rotor     structure strength design     strength design criteria     finite element analysis    

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标题 作者 时间 类型 操作

Impact analysis of compressor rotor blades of an aircraft engine

Y B SUDHIR SASTRY, B G KIROS, F HAILU, P R BUDARAPU

期刊论文

Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

期刊论文

A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

期刊论文

Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

期刊论文

用可压缩流涡方法模拟叶轮机动静叶的相互作用

陈矛章,彭波

期刊论文

Condition monitoring of a wind turbine generator using a standalone wind turbine emulator

Himani,Ratna DAHIYA

期刊论文

Two-sided ultrasonic surface rolling process of aeroengine blades based on on-machine noncontact measurement

Shulei YAO, Xian CAO, Shuang LIU, Kaiming ZHANG, Xiancheng ZHANG, Congyang GONG, Chengcheng ZHANG

期刊论文

Novel casting processes for single-crystal turbine blades of superalloys

Dexin MA

期刊论文

A novel NN based rotor flux MRAS to overcome low speed problems for rotor resistance estimation in vector

Venkadesan ARUNACHALAM,Himavathi SRINIVASAN,A. MUTHURAMALINGAM

期刊论文

Timing decision-making method of engine blades for predecisional remanufacturing based on reliability

Le CHEN, Xianlin WANG, Hua ZHANG, Xugang ZHANG, Binbin DAN

期刊论文

Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

期刊论文

Study on wave rotor refrigerators

Yuqiang DAI, Dapeng HU, Meixia DING

期刊论文

Application of high-turning bowed compressor stator to redesign of highly loaded fan stage

LI Shaobin, SU Jiexian, WANG Zhongqi

期刊论文

The computational fluid dynamic modeling of downwash flow field for a six-rotor UAV

Yongjun ZHENG, Shenghui YANG, Xingxing LIU, Jie WANG, Tomas NORTON, Jian CHEN, Yu TAN

期刊论文

Structure improvement and strength finite element analysis of VHP welded rotor of 700°C USC steam turbine

Jinyuan SHI,Zhicheng DENG,Yong WANG,Yu YANG

期刊论文