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Transactions of Tianjin University 2005年第1期11卷 59-65页

作者：张小刚宋玉普吴智敏 State Key Laboratory of Coastal Offshore Engineering Dalian University of Technology Dalian 116024 China

By means of fracture testing on roller-compacted concrete （RCC） three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.

关键词： roller-compacted concrete (RCC) arch dam induced crack double-K fracture parameters equivalent strength calculation model optimizing setting

calculation model for water influx and controlled reserves for CBM wells with high water yield

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Petroleum Research 2018年第3期3卷 288-292页

作者： Qing Feng Han Jia Zijun Huang Miao Tian Jingsong Li Xiaonan Li Oilfield Production Optimization Institution China Oilfield Services LimitedTianjin300450China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China

Compared with conventional gas reservoir,percolation mechanism of coalbed methane(CBM)is completely different,it is remarkably affected by adsorption/desorption performance,pressure variation and coalbed *** it is difficult to calculate the controlled reserves of CBM ***,the connection of edge-bottom water or interbedded water by fractures or faults may largely increase the water yield and drainage period,leading to obvious water invasion in some CBM *** are few literature about the predicted production for CBM wells with high water *** on the unconventional CBM reservoir,methods of pseudo geological reserves and production index curves are adopted to establish the calculation model of water influx and controlled *** further confirms that the calculation model is successfully applicated on the CBM wells at the middle part of Qinshui Basin in China.

关键词： CBM well High water yield Water influx Controlled reserves calculation model

Near ground air temperature calculation model based on heat transfer of vertical turbulent and horizontal air flow

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Journal of Central South University 2012年第3期19卷 721-726页

作者：张磊孟庆林 School of Architecture South China University of Technology

In order to calculate the air temperature of the near surface layer in urban environment,the surface layer air was divided into several sections in the vertical direction,and some energy balance equations were developed for each air layer,in which the heat exchange due to vertical turbulence and horizontal air flow was taken into ***,the vertical temperature distribution of the surface layer air was obtained through the coupled calculation using the energy balance equations of underlying surfaces and building ***,the measured air temperatures in a small area(with a horizontal scale of less than 500 m) and a large area(with a horizontal scale of more than 1 000 m) in Guangzhou in summer were used to validate the proposed *** calculated results accord well with the measured ones,with a maximum relative error of 4.18%.It is thus concluded that the proposed model is a high-accuracy method to theoretically analyze the urban heat island and the thermal environment.

关键词： turbulent heat exchange urban thermal environment near surface layer air temperature calculation model

calculation model of AC loss for CICC(cable-in-conduit conductor) based on strain

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Science China(Technological Sciences) 2012年第5期55卷 1132-1139页

作者： JIANG HuaWei WU SongTao ZHANG DeXian XU ZhaoHui ZHEN Tong College of Information Science and Engineering Henan University of TechnologyZhengzhou 450001China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China

The CICC (cable-in-conduit conductor) in ITER (International Thermal-nuclear Experimental Reactor) will run in high-current, fast transient magnet field and complex environment. In response to the impact of magnet fields above 10 T, the Nb3Sn conductor has been introduced. However, the AC (alternating current) loss mechanism of Nb3Sn conductor on strain has not been explored. So, it is necessary to study the AC loss calculation method with transient electromagnetic field and wide range of strain, the coupling current in complex field and current signal of field is simplified to the spectrum effects of coil excitation, and calculation technology of AC loss, which contains the frequency, magnet field, coil characteristics and other parameters, is constructed to meet the discrete Fourier transform (DFT). By comparative analysis of simulation, it is found that the AC loss calculation of the conductor with spectrum algorithm is closer to the actual project value than the traditional algorithm. For the rapid excitation, in particular plasma discharge and burst, spectrum algorithm and the traditional algorithm are consistent. For the relative error calculation of hysteresis loss and coupling loss, it is found that the coupling loss is cumulative linearly, where the hysteresis loss is not so. As a function of the amplitude, frequency and phase angle, the relative error is less than 40%. The results showed that the method of Fourier restructuring is satisfactory.

关键词： cable-in-conduit conductor (CICC) strain numeric simulation AC loss calculation model

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calculation model of edge carbon atoms in graphite particles for anode of lithium-ion batteries

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Transactions of Nonferrous Metals Society of China 2011年第11期21卷 2466-2475页

作者：张万红河南科技大学材料科学与工程学院洛阳471003

Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in different sites.A spherical close-packed model for graphite particle was *** fractions of surface carbon atoms（SCA） and edge carbon atoms（ECA） were derived in the expression of crystallographic parameters and particle size,and the effects of ECA on the initial irreversible capacity and the mechanisms of action were analyzed and *** results show that the atoms on the edge are more active for electrochemical reactions,such as electrolyte decomposition and tendency to form stable bond with other atoms and *** the practical graphite particle,corresponding modifying factors were introduced to revise the difference in calculating *** revised expression is suitable for the calculation of the fractions of SCA and ECA for carbon materials such as graphite,disordered carbon and modified graphite.

关键词： Li-ion batteries carbon anode calculation model electrochemical properties mechanism of action

Activity calculation model for Ternary Slag System of Al_2O_3-BaO-B_2O_3

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Journal of Iron and Steel Research International 2013年第11期20卷 46-50页

作者： ZHOU Jian WANG Qiang QIN Zhe QIU Sheng-tao GAN Yong ZHU Guo-ling National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute

According to the ion and molecule coexistence theory, the activity model of Al2O3- BaO-B2O3 ternary slag system was established, and the influences of BaO/Al2O3 molar ratio, B2O3 mole fraction and temperature on the activity of the slag system were investigated. Finally, the equal activity curves were drawn with the model results. The results show that with the increase of BaO/Al2O3 ratio, the activity of Al2O3 is significantly reduced, the activi- ty of BaO3-Al2O3 is increased obviously, and the activity of 2Al2O3· B2O3 is also decreased. With the increase of B2O3 mole fraction, the activity of BaO · Al2O3 decreased significantly, while the activities of BaO·B2O3 and 2Al2O3·B2O3 increased. In addition, the influence of temperature on the activities of different components is com paratively smaller than the influence of BaO/Al2O3 ratio and B2O3 mole fraction.

关键词： molecule and ion coexistence theory Al2O3- BaO-B2O3 ternary slag system activity calculation model

Experimental study on calculation model of labyrinth emitter discharge under subsurface drip irrigation

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International Journal of Agricultural and Biological Engineering 2014年第6期7卷 14-19页

作者： Hou Wen Bai Dan Zhou Wen Institute of Water Resources and Hydroelectric Engineering Xi'an University of TechnologyXi'an 710048China College of Conservancy North China University of Water Resources and Electric PowerZhengzhou 450011China

For different texture of soils,the grain composition is different with significant *** the emitter of subsurface drip irrigation(SDI)is buried in the soil,emitter discharge is influenced by soil *** experiment was conducted to investigate the relationship between the soil properties with emitter working pressure and emitter discharge of *** three different grain composition soils,and emitter working pressure,as well as soil clay content,soil bulk density and initial soil moisture content respectively as influence factors of emitter discharge of SDI,the experimental scheme was gained by uniform design.A calculation model for determination of the SDI emitter discharge was established by regression analysis with the first two kinds of soil test data,and its reliability was verified by the third kind of soil test *** model is simple with high accuracy,easy to use,and lays the foundation to study hydraulic elements of SDI field network,especially taking the soil clay content as an influencing factor has widened the scope of application of the *** achievement is of great significance for design and management of SDI.

关键词： subsurface drip irrigation emitter soil clay content discharge calculation model

Study on calculation model of High Speed Machine Silicon Steel Sheet Electromagnetic Characteristics Considering Magnetic, Stress and Temperature Condition

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CES Transactions on Electrical Machines and Systems 2022年第3期6卷 288-297页

作者： Yu Li Guangwei Liu Wenping Cao Fengge Zhang the School of Electrical Engineering Shenyang University of TechnologyShenyang and 110870China IEEE the School of Engineering and Applied Science Aston UniversityBirmingham and B47ETUK

High-speed motor has the characteristics of high frequency, high temperature, and more stress, resulting in the field distribution inside the motor being complicated. To better study the electromagnetic characteristics of silicon steel sheet for high-speed motor. In this article, a study on the calculation model of silicon sheet electromagnetic characteristics considers the effects of electromagnetic, stress, and temperature factors. The study is divided into two parts, one is to propose the calculation model of silicon steel sheet’s permeability;the other is to improve the calculation model of silicon steel sheet’s loss. Then, the magnetic field, stress field, and temperature field of a surface mount high speed permanent magnet motor(SMHSPMSM) are analyzed by finite element method(FEM), and the results under the consideration of magnetic, stress, and temperature factors are brought into the calculation model for calculation. Finally, the accuracy of the calculation model for electromagnetic characteristics of silicon steel sheet is verified by comparing the calculated results with the finite element results.

关键词： calculation model Silicon steel sheet Electromagnetic characteristics Magnetic Stress Temperature

Theoretical calculation model of Single Rip Tearing Strength for the Nonwoven Composites

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Journal of Donghua University(English Edition) 2005年第5期22卷 96-99页

作者：钱程 School of Clothing and An Designing Jiaxing College

The nonwoven composites have sandwich structure, with the first and third layers being nonwovens and the middle layer of woven fabric. On the basis of tests of the single rip tearing strength and drawing out resistances of both the nonwoven composites and the woven fabric, the single rip tearing failure mechanism of the composites were analyzed. Then theoretical calculation model for the single rip tearing strength was established, which indicates that the breaking strength of warp and weft yams in the nonwoven composites, the density of warp and weft yarns and drawing out resistances are the main influencing factors. In the end, experimental verification was made, which shows that theoretical values conform to the measured values well.

关键词： nonwoven composites single rip tearing strength calculation model

Leaf Area calculation model of *** and ***×***

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Agricultural Science & Technology 2010年第8期11卷 4-6,9页

作者：朱宏光赵金龙温远光侯日华广西大学林学院广西南宁530004

[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×***. [Method] The correlation between leaf area and leaf＇s eigenvalue of E. urophylla and E. grandis×*** were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×*** both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×*** both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species.

关键词： E. urophylla E. grandis×E.urophylla Leaf's eigenvalue Leaf area calculation model