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Wang T.-C.,Nanjing University of Aeronautics and Astronautics | Wang T.-C.,Jiangsu Key Laboratory of Precision and Micro Manufacturing Technology | Wang T.-C.,Wuxi TJInnova Auto design Co. | Yang A.-J.,Nanjing University of Aeronautics and Astronautics | Bu L.-F.,Harbin Electric Machinery Co.
Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice | Year: 2013

Due to the uncertain interval and the incomplete attribute information in the procedure of the complex mechanism scheme design, the multi-attribute extension gray relevant optimized decision-making problem of scheme design is studied. The methods for the multi-attribute decision making based on the grey system theory and the extension theory are analyzed. Based on the optimal extension gray relevant membership degree of design schemes, the multi-attribute extension gray relevant optimized decision-making model is developed. By adopting the gray-matter element, the multiple-attribute extension decision making matrix is standardized, and the dummy ideal region and the negative ideal region of gray-matter element with integrated attribute information are proposed. Then, the extension distance of gray information is presented, based on these, the optimum design scheme is achieved in the whole system. Finally, an example is provided to validate and prove its efficiency and feasibility.


Kang J.W.,Tsinghua University | Hao X.K.,Tsinghua University | Nie G.,Tsinghua University | Long H.M.,Tsinghua University | And 2 more authors.
IOP Conference Series: Materials Science and Engineering | Year: 2015

To improve the production efficiency and reduce residual stress and deformation, a new method-Post Solidification Intensive Riser Cooling (PSIRC) was proposed for heavy steel castings. Risers are cooled by forced air from its top surface as the solidification of a casting finishes, so, the risers are turned into cooling passages during the cooling process of a casting with contrast to their function of feeding passages during the solidification process. This method was applied to a hydro turbine blade with 0.9 ton melt. Its cooling speed increased apparently meanwhile with improved temperature distribution uniformity and the hot spot was pushed almost to the casting bottom. The cooling efficiency was improved 40% before shakeout and its residual stress was reduced meanwhile. © Published under licence by IOP Publishing Ltd.


Kang J.,Tsinghua University | Long H.,Tsinghua University | Li Y.,Tsinghua University | You R.,Tsinghua University | And 4 more authors.
Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science | Year: 2015

Researchers share their views on the discussion of observation of the mold filling process of a large hydro-turbine guide vane casting. The mold filling of liquid metals is very important, especially as the first step of making a casting. The researchers observe that the filling system design is by theories with the consideration of the factors such as experience, cost, pouring ladle, and easy-going with on-site workers. They also state that counter-gravity filling by using pressurized furnaces or pumps has been successfully applied in the production of aluminum castings.


Lu Y.-P.,Harbin University of Science and Technology | Zheng G.-L.,Harbin University of Science and Technology | Feng F.,Harbin University of Science and Technology | Qin Y.-S.,Harbin Electric Machinery Co. | Han J.-D.,Harbin University of Science and Technology
Dianji yu Kongzhi Xuebao/Electric Machines and Control | Year: 2010

In order to analyze the cooling effect of different ventilation proposals in the rotor, a physical model of single coil of the longest end winding was established for a large air-cooled turbine generator rotor, which can change the size and location of inlet and outlet as well as the block layout in the case of determining each ventilation segment length. In order to compare the cooling medium flow distribution of different ventilation proposals in rotor, the maximum temperature of the rotor winding and the uniformity of temperature distribution, the rotor flow field and temperature field of the rated operating conditions were simulated according to the computational fluid dynamics principle. The results show that the air inlet position of the rotor end windings determines the length of winding air road, the flow of cooling air, and the temperature distributions of the cooling medium and the winding. Rational arrangement of air inlet can increase the air mass flow rate entering the rotor winding, adjust the percentage of air mass flow rate entering each ventilation segment, ensure that the rotor worked at the temperature below the maximum allowable operating temperature and make the rotor temperature distribution be uniform.


Wang T.,Nanjing University of Aeronautics and Astronautics | Chen B.,Nanjing University of Aeronautics and Astronautics | Bu L.,Harbin Electric Machinery Co.
Nanjing Hangkong Hangtian Daxue Xuebao/Journal of Nanjing University of Aeronautics and Astronautics | Year: 2011

Due to the incomplete and the uncertain interval attribute information in the procedure of large-scale hydraulic turbine scheme design, the decision-making problem of the complex mechanism scheme design is studied. By using the information axiom of axiomatic design, the theory of mathematics and the information theory of Shannon are combined. Based on these, the computing method of interval information content is proposed and the proposed model for the multi-attribute optimal selection of interval number is developed. By comparing the interval information content, the optimum design scheme is achieved in the whole system with integrated interval weight information content and interval design information content of various indexes. Finally, an example of large-scale hydraulic turbine scheme design is provided to validate and prove its efficiency and feasibility.


Huo F.-Y.,Beijing Jiaotong University | Li Y.,Harbin University of Science and Technology | Li W.-L.,Harbin University of Science and Technology | Yang X.-F.,Harbin Electric Machinery Co.
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2010

With the increase of turbogenerator capacity, the heat transferability of cooling system is becoming more and more vital to the component reliability. By reasonablely optimizing the stator structure in a turbogenerator, utilization rate of coolant could be improved, and the maximum temperature of turbogenerator could be reduced. Based on the experimental data and plenty of related operations of a 200 MW air-cooled turbogenerator, two optimization designs about stator structure were proposed. One was to change the iron core thickness with the stableness of overall size, total losses of stator core and the number of stator ventilations, the other is to increase the number of ventilations and reduce their length with the stableness of the overall size and total losses of stator core. With CFD principle and 3-D finite volume method, the modeling equations of air turbulent flow in cooling ducts are solved, and the effect of the ventilations' structure changing on coolant utilization ratio and distribution of stator temperature were studied. The study shows that, by adopting the two optimal structures, coolant can take away more heat from generator and the maximum temperature of generator can be reduced up to 9.13°C more than original structure. © 2010 Chin. Soc. for Elec. Eng.


Wang T.-C.,Nanjing University of Aeronautics and Astronautics | Chen B.-F.,Nanjing University of Aeronautics and Astronautics | Bu L.-F.,Harbin Electric Machinery Co. | Wang W.,Harbin Electric Machinery Co.
Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS | Year: 2011

To improve efficiency of scheme design for large-scale hydraulic turbines, reasonable organization of design knowledge and its intelligent design made valuable contributions to design tasks. After describing the design knowledge with basic element, the basic element implication model of running selection and the data storage model were presented. And then, an improved searching and matching method of key points in running area was put forward, based on these, the data smooth model and the basic element interaction and judgment model of key points in running area were presented. Finally, an example of large-scale hydraulic turbines scheme design was provided to validate the efficiency and feasibility of the proposed models.


Wang T.-C.,Nanjing University of Aeronautics and Astronautics | Bu L.-F.,Harbin Electric Machinery Co. | Wang W.,Harbin Electric Machinery Co.
Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS | Year: 2011

Due to the complicated, multi-level, multi-attribute and creative process of product structure configuration of complex product scheme design, reasonable organization and reuse of design knowledge were guaranteed for improving product design efficiency. Based on multi-level case decomposition, multi-level case-based reasoning and reuse of scheme design knowledge were studied, a formal expression model of hierarchical association and conductivity reasoning for complex product scheme design was presented, conductivity effect function of multi-level reasoning process was established. And then, multi-level case-based reasoning algorithm was put forward and implementation process of initial design scheme was provided. Finally, an example was used to verify the effectiveness and feasibility of the model and algorithm.


Wang Q.,Harbin Institute of Technology | Xu Y.,Harbin Institute of Technology | Hu J.,Harbin Institute of Technology | Zou J.,Harbin Institute of Technology | Zhang J.,Harbin Electric Machinery Co.
IEEE Transactions on Plasma Science | Year: 2013

This paper presents an approach for enhancing the thrust force of a tubular transverse flux permanent magnet linear machine (TFPMLM) that has been developed for electromagnetic applications. It is shown that, by introducing auxiliary cores to suppress the leakage flux, the thrust force of the tubular TFPMLM can be significantly enhanced, by ∼130%$, under the same volumetric constraints. The effectiveness of the proposed technique is validated by extensive three-dimensional finite element computations. © 1973-2012 IEEE.


Wang T.,Nanjing University of Aeronautics and Astronautics | Chen B.,Nanjing University of Aeronautics and Astronautics | Bu L.,Harbin Electric Machinery Co.
Zhongguo Jixie Gongcheng/China Mechanical Engineering | Year: 2012

Due to the complicated, multi-hierarchy, multi-attribute and creative process of a mechanism scheme design configuration, an extension configuration model of the mechanism scheme design was proposed based on axiomatic design and the extension theory. By reusing the design cases, the axiomatic design frame of complex mechanism scheme design was developed. In the developed axiomatic design frame, the design object could be processed with extension transformation, extension data mining and dependent function foundation. Based on these, the volatilization extension design method and the implication extension design method were put forward. And then, the extension configuration model and the corresponding algorithm were presented. Finally, an example was provided to the examine the model and algorithm.

Loading Harbin Electric Machinery Co. collaborators
Loading Harbin Electric Machinery Co. collaborators