Advanced Materials Research Vols. 706-708

Abstract: Use Gambit and Fluent to the servo valve armature component of squeak problem undertook CFD is analyzed, simulates the flow field distribution in internal circuit structure, found in the servo valve armature component whistle when fluid in the inner of the product, produced a marked a negative pressure zone, and in this context the armature assembly stress sharply change, causing the armature assembly vibration squeal, changing the internal structure of the product again CFD simulation, negative pressure area disappeared, the pressure change tends to be steady, the structure of the product was the actual through pressure liquid servo valve test, howling problem solved.

Abstract: This paper puts forward a comprehensive evaluation method of regional power grid power quality, and introduces its application with real measurement data. Firstly, the conception of regional power grid power quality evaluation is proposed. And a power quality indexes system, which contained the comprehensive power quality indexes, is designed on the basis of six national standards. Secondly, the evaluation objects are divided into two levels, then the comprehensive evaluation of regional power grid power quality is achieved with weighting the subsystems and large-scale systems by scatter degree method and improved analytic hierarchy process-G1 method. Finally, according to the data presented by power quality online surveillance system of Guangzhou power supply bureau, the suitability and validity is proved by the method of area pigmentation.

Abstract: By using UG and ADAMS software, the mechanical system and hydraulic system model of excavator working device are established. Moreover, together with the application of the parameters of the ADAMS associated technology, the virtual prototyping model of mechanical excavator and hydraulic integration are established; These two software also work on the motion simulation, as well as the optimization analysis of the main components of the system. This parameter association technology research method is characterized by a comprehensive analysis both of the dynamic and static situations. The results provide some reference value for the feasibility of the design and the manufacture of the virtual samples. Meanwhile, it provides some theoretical and engineering significance.

Abstract: The vertical machining center workbench solid modal had been built through Pro/E , the static stiffness analysis had been computed by using the finite element software ANSYS, and the workbench static stiffness had been checked according to the calculated result. To lose weight as optimal objective,by using the topological optimization function of ANSYS software, and take into account the stress condition and manufacturing process, the structure of the workbench was improved, the static stiffness was the same as original design. Comparing with the original design, the weight of the optimized structure was reduced by 12%.

Abstract: As the important content of modern design method, virtual design plays a key role in machine system optimal design. The VDT (Virtual Design Technology) is discussed in detail. The flow of virtual design is given. Based on the flow of virtual design, the application of virtual design to container loading device is studied.

Abstract: The lumped mass model of an aviation herringbone gear is established, which takes coupling relationship between the two helical gear into consideration. Based on this model, motional differential equation is derived, and excitation parameters of gear pair are calculated at the same time. The dynamic differential equations are solved to obtain the dynamic response of each degree of freedom, then vibration characteristics of aviation herringbone gear in different speed and power is analyzed and the appropriate rotational speed and power of different flight status is determined. Research on the reliability analysis of aviation herringbone gear and the dynamic efficiency analysis is of great significance.

Abstract: Vibration in turning processing is associated with free vibration, forced vibration and self-excited vibration, the composition and machine tool, tool and workpiece process system dynamic characteristic.A detailed analysis of the main types of vibration in turning and the causes, and put forward from the aspects of cutting tool, fixture, cutting process, reduce or eliminate vibration measures.

Abstract: With some ballistic missile erecting system as subject, a virtual prototype is constructed, for virtual measuring of the load spectrum of the erecting system. By FEM analysis and damage analysis, the dangerous position of is uncovered, and the stress-time history is obtained. By use of material fatigue feature curve in combination with the stress-time history, the fatigue life of system components is studied.

Abstract: The forces on fiber in the low consistency pulp are studied in flow field. Eulerian model is analyzed combining with the forces to provide modified continuity equation, momentum equation and energy equation, which facilitates the flow pattern research of low consistency pulp by using of the fluid dynamics models and fluid dynamics equations.

Abstract: The P wave propagation in the functionally graded materials (FGM) is studied. The differential equation with varied-coefficient of wave motion in the FGM is established. By using of the WKBJ approximation method, the differential equation with varied-coefficient is solved, and the closed-analytical solutions of displacement in the FGM are obtained. The properties of the FGM whose shear modulus and mass density are gradually varying in exponential form are calculated; the curves of P wave velocity and amplitude, and the general properties of the P wave in the FGM are analyzed.