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51.
应用陀螺力学理论,对传统动力总成悬置系统的无阻尼动力学方程进行修正,引入陀螺矩阵,得到新的动力学方程。对新的动力总成悬置系统动力学模型进行计算分析,研究了陀螺矩阵对频域、时域响应的影响。使用遗传算法分别对修改前后的方程进行优化计算,并进行比较分析。结果表明,对于低转速发动机,曲轴转动的陀螺效应不明显,而对于高转速的发动机,陀螺效应不能忽略,应以考虑陀螺力矩的方程为基础进行设计分析。 相似文献
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对砌石拱坝的加高倍厚中新、老坝体结构面,用有限元软件ANSYS结合接触理论进行计算,并分析结果得出:温升、水压力和淤沙压力使结合面上的接触压力增大,从而接触摩擦应力较大,有利于结合面的结合,而结合面在温降的作用下有脱离的趋势。 相似文献
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This paper analyzes the fluid flow and heat transfer of the heat exchanger, and obtainsd the distribution of fluid field, heat field and pressure field in heat exchanger. According the analysis result, some modify measure is adopted, such as decreasing the number of tube bundle, the size of baffle plate and increasing the diameter of exchange heat tube. In the new heat exchanger, the resistance decreased 32.3%, is 103.2 Pa and the temperature of the exit is 130 K. The new heat exchanger satisfies the requirement of exchanging heat. The study indicates that adopting the numerical simulation method could get temperature, pressure and fluid - velocity of anywhere of the heat exchanger, and understand effecfing of structure parameter on fluid flied and heat flied of the heat exchanger. Therefore, it provides a new method for optimization design of heat exchanger. 相似文献
56.
Wang Bingle Song Liquan 《保鲜与加工》1988,(2)
This paper presents a new method by using mass and acceleration parameters for balancing inertial force of mechanism. Compared with other balance methods, this one is simple, clear and superior in regularity when the balancing equation of complex mechanism is established, and its solving procedure is also easy. The new methcd is convenient to learn and use as well as convenient to program. 相似文献
57.
In view of the vehicle cornering or path changing under ultimate handling maneuver, a 3-DOF nonlinear vehicle dynamics model which takes the vehicle lateral velocity, yaw rate and body roll angle as the State variables is presented. Based on the dynamic analysis, the method which using additional yaw moment produced by different longitudinal braking force among each wheels to improving vehicle handling stability in emergency situations is discussed. Considering the sideslip angle as one of the vehicle state variables is difficult to measuring, the sideslip angle estimation based on vehicle dynamic model and kinematics is designed. And then, based on the theory of siding model control, the combining sliding model control system is founded, which taking the vehicle yaw rate and body side-slip angle errors between the estimated and the real as the input variables, and taking the braking torque and the steering angle as control aims. The simulation results indicate that the control method can effectively improve the vehicle lateral handling stability. 相似文献
58.
DUAN Shao-guang 《保鲜与加工》2004,(11):66-70
The contact number is an important mathematical tool of systems theory and methods in the monograph Set Pair Analysis and Its Preliminary Applications written by Zhao Keqin for unitizedly processing the uncertainties due to the fuzzy, stochastic, intermediate and information uncomplete about something. The article applies the multivector algebra which is isomorphism with the real Dirac algebra in the real space-time adopted by Venzo de Sabbata to the contact number of set pair analysis, and consequently, the contact number is generalized correspondingly. 相似文献
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Li Runfang Li Yusheng 《保鲜与加工》1993,(1):96-101
A new finite element method is presented in this paper to analyze the thermo-
elastic contact problem with heat input on meshing tooth faces. The computational model of meshing gear has been established and the frictional heat input on meshing tooth faces is estimated. In addition, 2-D finite element analysis program for this kind of problem is listed. The test and practical examples are given to show the validity and versatility of this method. 相似文献