Papers by Keyword: Structural Parameters

Abstract: The structural - elastic properties correlations have been studied for polycrystalline spinel ferrite system, Zn_xCo_1-xFe₂O_4, x = 0.0-0.6, at 300 K. The cation distribution formulae determined from X-ray diffraction line intensity calculations are used to calculate bulk modulus (K_o) in particular and Young′s modulus (E₀), rigidity modulus (G₀), longitudinal modulus (L₀) and Lame′s constant (λ_L0) in general. The longitudinal wave velocity (V_l0) and transverse wave velocity (V_so) computed from empirical relation based on X-ray density and mean atomic weight is used to calculate L₀ and G₀ respectively. The applicability of the heterogeneous metal mixture rule for theoretical estimation of elastic constants has been tested. The results are compared with elastic moduli determined from conventional ultrasonic pulse transmission technique and causes for the observed difference between the two have been discussed.

Abstract: In a hierarchical system, grading wheel plays a very important role in material scattering and classifying. This article calculates the critical speed of the grading wheel rotor, a small part of the SZ spin flash dryer, based on finite element analysis software ANSYS. Meanwhile, in order to provide a theoretical evidence for the design of the grading wheel’s dynamic performance, analyze the influence of the bearing’s radial stiffness and some geometry parameters of the structure on the critical speed, including bearing stiffness, bearing span, cantilever length and wheel’s weigth. The result indicates that bearing span is approximately proportional to the critical speed, the cantilever length and runner quality are inversely proportional to the critical speed and the bearing span and the cantilever length have a greater impact on the critical speed.The final purpose of this paper is to find a set of proper parameters on the basis of the analysis result and optimize the rotor’s structure.

Abstract: Design of a new magnetorheological damper gap structure, combined with viscous lag model, analyzed the damper structural parameters, Design the damping devices with different sizes. Comparison of the structure of the damper with different sizes after experiment, finding that the structure parameters has a significant effect on the performance of the damper. Designing a reasonable clearance structure is very important for improving the performance of MRF damper． The experimental results and the model fit have a good fitting accuracy.

Abstract: Shield tunning method has been used widely in urban underground engineering. Based on a certain range of Wuhan subway shield tunnel, the subway shield tunnel segment of the internal force and deformation were studied by the load structure method and stratum structure method. Influence of the formation parameters and the parameters of the lining structure on the segment internal force and deformation was analyzed. And the tunnel construction was modeled by three-dimensional dynamic finite element method. The influence of the construction process about ground subsidence and segment stress was discussed, in order to guide urban subway tunnel construction design.

Abstract: The vibration power flow characteristics of the fully simply supported laminate structure subjected to different excitation frequencies was discussed. Based on the layer-wise theory with finite element models, the effects of panel orientation angle, elastic modulus ratio and width-depth ratio on the power flow of the laminated composite plates were discussed, and the corresponding power flow - frequency streamlines were given. From present results, it can be demonstrated that the panel orientation angle and width-depth ratio have a greater impact on vibration power flow. Further, the information above can be used to control the noise level of the structural vibration.

Abstract: Isolation Control System Based on MRF magneto-rheological dampers analyze the structure and mechanical properties for engine isolation, the establishment of magnetorheological damper damping force of the theoretical model to clarify the magnetic current variable damper structural parameters, the motion parameters change its relationship performance impact of electromagnetic fields on the magneto-rheological dampers for numerical calculations. Research magnetorheological engine mounts intelligent control, real-time damping force adjustment, so that the vibration of the engine is transmitted to support the most effective attenuation of the time.