Variation Rules Of Parameters Research Articles

Gradual Change Reliability Sensitivity Design for Tool Based on Measured Information

It brings certain error to reliability design of mechanical components that now most reliability design aiming at establishing pure theoretical mathematical model, without considering arbitrary distribution and variation rules of parameters. In this paper, the variation rules of strength and load effect are studied, the computational method of gradual change reliability is given. By combining the theory of reliability design with the method of sensitivity analysis, the restrictions on random variable distribution types are loosen, the gradual change reliability sensitivity design method with arbitrary distribution parameter is proposed based on the measurement information. Under the circumstance that knowing the first four order moments of basic random parameter, reliability sensitivity design with arbitrary distribution parameter can be brought about by using computer program, which provides the theoretical basis for structural design and life forecast of mechanical components.

Experimental Simulation on Aerodynamic Character of D-Shaped Iced Conductor

The dynamics force of iced-conductor is the driving force of galloping; its variation is depended on the aerodynamic character of iced conductor. The aerodynamic character of iced conductor is the key factor of galloping of iced-conductor, but the result of theoretically analysis and numerical simulation isn’t suited for the requirement of transmission line project. In the paper, basing on the theoretically analysis and numerical simulation, the simulation tests in wind tunnel of D-shaped iced conductor is stetted up and put into practice under different wind speed and iced thickness, and then the systemic study is carried into execution. The result of research is indicated that there is a better coherence between the numerical simulation and experiment test, and the variation rules of parameters is obvious with the different iced thickness, the result of numerical simulation is the beneficial supplement to the experiment test. The result can not only provide the original date for the galloping analysis, but also validate the affectivity of numerical simulation, support the research of mechanism and control of galloping.