各项工作都要进行经济效果比较从中选出花钱少,收获大的最优方案,这是一条十分重要的方针,开发系统工程,有利于完善地实现这方针,下面就开发系统工程的必要性,基本建设过程中发展系统已具备条件,怎样开发基本建设系统工程及建立数学仿...各项工作都要进行经济效果比较从中选出花钱少,收获大的最优方案,这是一条十分重要的方针,开发系统工程,有利于完善地实现这方针,下面就开发系统工程的必要性,基本建设过程中发展系统已具备条件,怎样开发基本建设系统工程及建立数学仿真模型,分别论述。系统工程的理论及方法还在发展中,自己的体会也要不断地深化,尤其七十年代蓬勃发展的大系统理沦(Large Scale System Theory)在国外、国内都有不同的看法,还在探讨之中。展开更多
A slotting method for cosine gears was proposed by using the involute cutter based on the conjugate theories of digital surface and gear meshing. The slotting model between the cosine tooth surface represented by disc...A slotting method for cosine gears was proposed by using the involute cutter based on the conjugate theories of digital surface and gear meshing. The slotting model between the cosine tooth surface represented by discrete points and the cutter figuration determined by analytic function was built for their geometrical relationship and conjugate motion during the machining process. Conjugate points in the cutter section corresponding to the discrete points on the cosine gear tooth surface and the conjugate movements were solved. By using the flexible control of the CNC procedure, the active control of the cutting trace of the slotting cutter was accomplished and the envelop forming of the cosine gear was obtained. Based on the software C++ and Matlab, the computer aided manufacturing(CAM) system of the cosine gear was developed, and the simulation of the slotting process was accomplished. Several examples were provided to illustrate the approach. The result of the simulation demonstrates that the proposed slotting method is feasible.展开更多
An improved whole model of beam pumping system was built. In the detail, for surface transmission system(STS), a new mathematical model was established considering the influence of some factors on the STS's torsio...An improved whole model of beam pumping system was built. In the detail, for surface transmission system(STS), a new mathematical model was established considering the influence of some factors on the STS's torsional vibration, such as the time variation characteristic of equivalent stiffness of belt and equivalent rotational inertia of crank. For the sucker rod string(SRS), an improved mathematical model was built considering the influence of some parameters on the SRS's longitudinal vibration, such as the nonlinear friction of plunger, hydraulic loss of pump and clearance leakage. The dynamic response and system efficiency of whole system were analyzed. The results show that there is a jumping phenomenon in the amplitude frequency curve, and the system efficiency is sensitive to motor power, pump diameter, stroke number, ratio of gas and oil, and submergence depth. The simulation results have important significance for improving the efficiency of beam pumping system.展开更多
A mathematical model of gear tooth profiles using the ellipse curve, whose curvature is convenient to control by changing the mathematical parameters as its line of action, was built based on the meshing theory. The e...A mathematical model of gear tooth profiles using the ellipse curve, whose curvature is convenient to control by changing the mathematical parameters as its line of action, was built based on the meshing theory. The equation of undercutting condition was derived from the model. A special epicycloidal tooth profile was also presented. An example gear drive with variation of the ellipse parameters was taken to illustrate the proposed method. The contact ratio of the gear drive designed by the proposed method was analyzed. A comparison of the property of the gear drive designed with the involute gear drive was also carried out. The results confirm that the proposed gear drive has higher contact ratio in comparison with the involute gear drive.展开更多
文摘各项工作都要进行经济效果比较从中选出花钱少,收获大的最优方案,这是一条十分重要的方针,开发系统工程,有利于完善地实现这方针,下面就开发系统工程的必要性,基本建设过程中发展系统已具备条件,怎样开发基本建设系统工程及建立数学仿真模型,分别论述。系统工程的理论及方法还在发展中,自己的体会也要不断地深化,尤其七十年代蓬勃发展的大系统理沦(Large Scale System Theory)在国外、国内都有不同的看法,还在探讨之中。
基金Projects(51205335,50975242,51375411) supported by the National Natural Science Foundation of ChinaProject(2013J01209) supported by the Natural Science Foundation of Fujian Province,China
文摘A slotting method for cosine gears was proposed by using the involute cutter based on the conjugate theories of digital surface and gear meshing. The slotting model between the cosine tooth surface represented by discrete points and the cutter figuration determined by analytic function was built for their geometrical relationship and conjugate motion during the machining process. Conjugate points in the cutter section corresponding to the discrete points on the cosine gear tooth surface and the conjugate movements were solved. By using the flexible control of the CNC procedure, the active control of the cutting trace of the slotting cutter was accomplished and the envelop forming of the cosine gear was obtained. Based on the software C++ and Matlab, the computer aided manufacturing(CAM) system of the cosine gear was developed, and the simulation of the slotting process was accomplished. Several examples were provided to illustrate the approach. The result of the simulation demonstrates that the proposed slotting method is feasible.
基金Projects(50974108,51174175) supported by the National Natural Science Foundation of China
文摘An improved whole model of beam pumping system was built. In the detail, for surface transmission system(STS), a new mathematical model was established considering the influence of some factors on the STS's torsional vibration, such as the time variation characteristic of equivalent stiffness of belt and equivalent rotational inertia of crank. For the sucker rod string(SRS), an improved mathematical model was built considering the influence of some parameters on the SRS's longitudinal vibration, such as the nonlinear friction of plunger, hydraulic loss of pump and clearance leakage. The dynamic response and system efficiency of whole system were analyzed. The results show that there is a jumping phenomenon in the amplitude frequency curve, and the system efficiency is sensitive to motor power, pump diameter, stroke number, ratio of gas and oil, and submergence depth. The simulation results have important significance for improving the efficiency of beam pumping system.
基金Projects(51205335,51375411)supported by the National Natural Science Foundation of ChinaProjects(2013J01209,2012J01237)supported by the Natural Science Foundation of Fujian Province,China+2 种基金Project(2014H0049)supported by the Major S&T Program of Fujian Province,ChinaProject(E201400800)supported by the International Cooperation and Exchange Research Plan of Xiamen University of Technology,ChinaProject(YKJ14008R)supported by the Scientific Research for the High Level Talent of Xiamen University of Technology,China
文摘A mathematical model of gear tooth profiles using the ellipse curve, whose curvature is convenient to control by changing the mathematical parameters as its line of action, was built based on the meshing theory. The equation of undercutting condition was derived from the model. A special epicycloidal tooth profile was also presented. An example gear drive with variation of the ellipse parameters was taken to illustrate the proposed method. The contact ratio of the gear drive designed by the proposed method was analyzed. A comparison of the property of the gear drive designed with the involute gear drive was also carried out. The results confirm that the proposed gear drive has higher contact ratio in comparison with the involute gear drive.
