共查询到20条相似文献，搜索用时 31 毫秒
1.
Gong Daoxiang Zhang Jianjun 《保鲜与加工》1992,(1):84-89
Based on the forming and meshing theories of gears, the relationship between machining parameters and driving quatity of straight bevel gears has been discussed. The forming and meshing processes have been simulated with a microcomputer. The correctness of the theoretical analysis and calculation has been proved by shaping experiment. 相似文献
2.
Gong Daoxiang Zhang Jianjun Zhen Changqi 《保鲜与加工》1993,(1):84-89
Because of their machining characteristics,Klinglnberg' s sprial bevel gears have the advantage over Gleason' s in many ways,so that they are more and more widely used. This paper analyzes the meshing and machining properties of the gears and deduces the equations,normal curveture and contact ratio of tooth surface. It also lays a solid foundation for spreading and importing the Klinglnberg' s machine,and developing klinglnberg' s gears. 相似文献
3.
Lu Runfang Ding Yusheng Li Yusheng Tang Qingping 《保鲜与加工》1993,(1):58-63
In this paper,both non-coupled numerical method of thermo-elastic deformation and coupled procedure for meshing gear are presented. The illustrative examples of gears applied in machine-tools and rolling mills show that this procedure is ralid and efficient. 相似文献
4.
Li Runfang Tang Qingping Chen Daliang 《保鲜与加工》1992,(3):11-14
In this Paper, a new automatic mesh generation scheme is present, which combine the teeth contact analysis with the modelling of finite element cotact analysis. This procedure is different from the ordinary auto - mesh - generation scheme. The presentation of this new procedure makes it possible to analyze the elastic contact problem of meshing gears by a finite element method. 相似文献
5.
In order to study the vibration characteristics and radiation noise of wind power speed-increase gearbox, a torsional vibration model of wind power speed-increase gearbox is established based on the analysis of supporting stiffness of bearing and contact stiffness of gear pairs. By solving the vibration differential equation with the help of Matlab, the frequency and corresponding vibration mode are obtained. With taking stiffness excitation, error exaction and meshing impact exaction into account, the dynamic finite element model of speed-increase gearbox is set up, and the dynamic response simulation is carried out. Regarding vibration displacement of the nodes on gearbox surface as boundary condition, an acoustic boundary element model of speed-increase gearbox is built. The surface acoustic pressure of gearbox and the radiation noise of field points are solved by the direct boundary element method. The results show that there is a great difference between torsion frequency and excitation frequency of wind power speed-increase gearbox, and so the resonance doesn't occur. The maximum structural noise and radiation noise mainly appear near the double octave of the gears meshing frequency of high-speed grade. 相似文献
6.
In order to fully research the effects of external excitations, such as wind speed, wind direction and voltage disturbance, on a grid connected wind turbine with doubly fed induction generator, a co-simulation model of MW-class wind turbine system is established by using Simpack and Matlab/Simulink software. Also, by considering the actual control strategies in the process of simulation, the relationship between external excitations and mechanical system is studied. According to time-domain simulation under the turbulent wind condition, the dynamic meshing forces of gears are analyzed. Besides, the vibration responses of tower are calculated under the different external excitations. Research results lay a foundation for dynamic performance optimization and reliability design of a wind turbine. 相似文献
7.
Numerical models based on FLAC 3D are difficult to build. A new kind of method modeling and meshing in the CATIA software, named the CATIA-FLAC 3D coupled modeling method, was proposed. This method utilizes the powerful geological modeling capabilities of CATIA for three-dimensional geological body modeling and meshing. And then, the interface program of CATIA-FLAC 3D is adopted to export the information into FLAC 3D, which is coded by visual basic language based on the variance of nodes and elements between the two software. The new proposed method was used in a bias tunnel through a mountain, and the results verified the feasibility and effectiveness of the proposed method. 相似文献
8.
Long Hui Zhang Guanghui 《保鲜与加工》1993,(1):102-106
By using the finite element elastic contact analysis method combined with the I-DEAS engineering analysis software, this paper studies the strength of the cone roller enveloping worm gearing,which is a new type of worm gearing transmission,on SUN-4 working station. It also analyzes loading distribution among meshing gears, the contact force distribution along the contact line ,the bending stress distribution and the contact stress distribution of the cone roller enveloping worm gearing with three-tooth meshing instantaneously. Besides,it provides the theoretic basis in the further researches for the new type of worm gearing transmission. 相似文献
9.
To investigate the work condition of the aircraft actuators in high temperatureheat transfer process of the output unit of a cycloidal reducer of the actuator is taken into account by Unigraphics NXHypermesh and ANSYS softwares based on finite element analysis(FEA).The temperature distribution of the output unit is obtained by meshing modelapplying loads and solving discrete problems.Thenthe temperature variation of the output unit is gotten by sampling and processing the data of FEA results.In the endthree main conclusions are drawn.Firstthe heat transfer process of the output units of cycloidal reducers of actuators can be analyzed by FEA efficiently.Secondthe temperature of the rudder and the design position of cycloid gears are two major factors in the operating life of reducers.Thirdthe operating life can be improved by lowering the rudder temperature and installing the cycloidal gear as far as possible away from the heat source. 相似文献
10.
Wang Dongyun 《保鲜与加工》1991,(1)
The environmental effects of discharge from construction sites are dis-cussed in this paper.According to its features,the discharge is classified.Based on the environmental physics,environmental chemistry cnvironmental biology,the harmful leffects of discharge and the necessity of cnvironmental protection in the construction sites
are expounded. 相似文献
11.
Long time partial discharge is bad for transfomers inside insulation and now partial discharge monitoring is not satisfactory because of electromagnetic interference and noise interference .This is a new way via dissolved gases concentration analysis to find partial discharge and acconding to diagnosis system to confirm partial discharge level. A basic research has been carried out to discover the correspondence relationship between partial discharge level and dissolved gases concentration,some valuable laws are gained for the first time. 相似文献
12.
The coaxial configuration of gas-insulated substations is of great advantages transmitting the electromagnetic wave excitated by partial discharge and of great advantages of partial discharge detection. Based the characteristics of configuration of GIS and PD signals inside, the authors design a disc coupler and a loop coupler for continuous monitoring of partial discharge in GIS, and analyze the sensor's characteristics theoretically. The frequency response (FR) characteristics of the disc coupler and the loop coupler are analyzed by the simulation and measurement realistically of square wave response. In addition, the measured results of partial discharge by the sensors designed in GIS are given, and it is shown that the sensors designed are available for the measurement of partial discharge in GIS. 相似文献
13.
Four physical models of typical internal insulation defects in 110 kV cable joints are designed and a test platform for partial discharge (PD) research on cable accessories also is constructed. Based on the models, plenty of PD data are obtained for vario 相似文献
14.
15.
TANG Ju~ WEI Gang~ SHI Hai-jun~ SUN Cai-xin~ ZHU Wei~ gy under the State Ministry of Education Chongqing University Chongqing Chin .Changshu Power Supply bureau Jiangsu Eelectric Power Company Changshu Chin 《保鲜与加工》2004,(4):1-5
The possibility of UHF (ultra high frequency) method used in partial discharge detection in GIS is analyzed, and the UHF sensor, simulating passive filter, detecting the method of wide-band and narrow-band are studied, in order to avoid interferes of low-frequency. The authors develop an inner loop sensor in GIS model and investigate UHF method detecting partial discharge in GIS. The results indicate that the UHF system of detecting PD can effectively detect partial discharge and avoid outer corona interfere and Periodic pulse interfere. At the same time, narrow-frequency PD detection is an effective detection method to restrain UHF interferes. 相似文献
16.
目的 用B.melitensis 16M提纯的LPS和O链抗原作为检测抗原，研制出针对B.melitensis 16M的单克隆抗体（McAb），将其标记胶体金，建立一种诊断布病的胶体金免疫层析方法。方法 B.melitensis 16M全菌免疫Balb/C小鼠，采用杂交瘤细胞技术制备McAb，测定免疫球蛋白亚类及亲和力。用HiTrap Protein G HP亲和层析纯化抗体并用胶体金标记，建立胶体金免疫层析方法。选择最佳反应模式组装成试纸条，对其特异性、敏感性、稳定性、阳性病料试验。结果 筛选出能稳定分泌抗B.melitensis 16M的种特异性单克隆抗体杂交瘤细胞株2D10、3C6、1E10，单抗亚类分别为IgG2a、IgG1，亲和常数（k）介于1×10-8~2.6×10-10。根据配对实验，以3C6为最佳包被抗体，2D10为最佳金标抗体。抗体IgG标记浓度为30μg/ml时，检测效果最佳。同时，与B.melitensis 16M多抗IgG作为包被抗体、2D10为金标抗体的检测体系对比，两种包被方法组装的试纸条最低检出量为5.0×103CFU/ml，且不与其它菌发生交叉反应，保持期≥100d。以荧光定量PCR为参照，试纸条检测80份阳性病料，检检出率为100%。结论 建立的胶体金免疫层析方法检测B.melitensis 16M快速、简便、可靠，有望开发成为布病快速诊断试剂盒。 相似文献
17.
In order to reduce the volume and be used in portable instruments, a line-cylinder atmospheric glow discharge device with a 1.92 mm discharge gap is designed. It mainly consists of an inner line electrode and an outer cylinder electrode. The diameters of the line and cylinder electrodes are 0.16 and 4 mm, respectively. The transition from corona discharge to glow discharge is observed and explained. By using discharge waveform and photo, it has been verified that it is a glow discharge. The calculation methods of vibrational temperature and rotational temperature are deduced by use of the N2 second positive band system. The emission spectrum of the plasma is collected by spectrometer (Acton Spectrapro 2500i). From calculation, it is found that the vibrational temperature of the plasma is about 2 360 K and the rotational temperature of the plasma is about 830 K. The device is used as an ion source in the ambient mass spectrometer. The experiment results show that the plasma generated by DC glow discharge can well ionize the formic acid, acetic acid, and phenol, etc. 相似文献
18.
研究了不同温度、压力和时间条件下,高密度二氧化碳(DPCD)处理对蛋清液中沙门氏菌和大肠杆菌的杀菌效果,并对DPCD处理蛋清液中大肠杆菌的杀菌动力学进行了分析。结果表明,在15 MPa,45℃下DPCD处理60 min,沙门氏菌和大肠杆菌分别降低了4.46和5.57个对数值,其中大肠杆菌对DPCD处理较沙门氏菌敏感。30 MPa,45℃,DPCD处理30 min,可以完全杀灭蛋清液中的大肠杆菌。线性模型能较好地拟合DPCD对大肠杆菌的杀菌效果,其中30 MPa,45℃下D值最小为5.830。 相似文献
19.
《Journal of Agronomy and Crop Science》1987,158(4):287-288
Book Reviewed in this article:
Meier, B., Pflanzenschutz im Feldbau — Tierische Schädlinge und Pflanzenkrankheiten.
Ammon, H. U., L. Stalder und U. Niggli, Pflanzenschutz im Feldbau — Unkrautbekämp-fung.
Pharis, R. P., and D. M. Reid; with contributions by F. D. B eall , D. E. B ilderback , M. L. B renner , D. C anary , J. V. C arter , D. J. C halmers , W. K. C oleman , D. S. F ensom , W. P. H ackett , H. I maseki , M. J. J affe , J. O. J ohnson , W. L. K oukkari , N. G. M arinos , J. P. M ascarenhas , T. O'B rien , J. H. P almer , G. F. P egg , R. P. P haris , B. G. P ickard , D. M. R eid , F. B. S alisbury , H. S mith , T. A. T horpe , D. V ince -P rue , R. L. W ample , S. B. W arde , R. J. W eaver , R. H. Z immerman . Hormonal Regulation of Development III; Role of Environmental Factors. Vol. 11 of Encyclopedia of Plant Physiology, New Series (Eds.: A. P irson and M. H. Z immermann ).
Renner, E., Statistikprogramme in Basic. 相似文献
Meier, B., Pflanzenschutz im Feldbau — Tierische Schädlinge und Pflanzenkrankheiten.
Ammon, H. U., L. Stalder und U. Niggli, Pflanzenschutz im Feldbau — Unkrautbekämp-fung.
Pharis, R. P., and D. M. Reid; with contributions by F. D. B eall , D. E. B ilderback , M. L. B renner , D. C anary , J. V. C arter , D. J. C halmers , W. K. C oleman , D. S. F ensom , W. P. H ackett , H. I maseki , M. J. J affe , J. O. J ohnson , W. L. K oukkari , N. G. M arinos , J. P. M ascarenhas , T. O'B rien , J. H. P almer , G. F. P egg , R. P. P haris , B. G. P ickard , D. M. R eid , F. B. S alisbury , H. S mith , T. A. T horpe , D. V ince -P rue , R. L. W ample , S. B. W arde , R. J. W eaver , R. H. Z immerman . Hormonal Regulation of Development III; Role of Environmental Factors. Vol. 11 of Encyclopedia of Plant Physiology, New Series (Eds.: A. P irson and M. H. Z immermann ).
Renner, E., Statistikprogramme in Basic. 相似文献
20.
排污权交易制度研究的理论基础 总被引：1，自引：0，他引：1
研究排污权交易制度的理论基础,是为了在理论上对其内涵有更为具体的理解和认识,在实践中有助于自觉而理性地对待和应用排污权交易制度。文章在相关文献的基础上,采用实证描述与规范研究分析方法,通过对环境问题产生的根源追溯,主要从环境外部性理论、公地悲剧理论、资源稀缺理论、市场失灵理论、科斯定理、政府失灵理论、制度变迁理论等方面探讨排污权交易制度的理论支撑。研究表明,没有固定的政府干预理论模式,也不存在完全的市场导向实践模式,任何模式都有发挥自身作用的空间。排污权交易制度是一个双赢的制度安排,折射了政府干预和市场化交易这两大学术思想的交融,是现代市场经济发展的趋势和必然结果,其背后是市场的自由运行,是政府角色和职能的转换,是经济发展制度保障的完善。 相似文献