Advanced Engineering Forum Vols. 2-3

Abstract: Through the cracking failure analysis of dump truck frame with large electric wheel, the static and dynamic frame analysis of performance evaluation are conducted by the finite element analysis method. From the strength and stiffness analysis frame structure in the weak links, it is easy to find out crack the parts and the reasons with frame, and through the modal analysis and random vibration and fatigue strength analysis the danger frequency of the frame induced by road encourage is obtained, which can prevent the occurrence of frame cracks and provide a foundation for further optimization of the frame.

Abstract: According to the vibration happened in rolling process of 1780 tandem rolling mill. Finite element method and structural dynamic method were used to analysis in this paper. The natural frequencies of the rack were calculated. The comparision between two methods were done. It was helpful for designing and reducing vibration of the rolling process.

Abstract: Finite element method and structural mechanics method are used to study the blast furnace shell modal analysis and the natural frequencies and mode shapes have been calculated. The two methods were compared and validated , and the results provide a theoretical foundation for the anti-vibration capabilities design of blast furnace shell in the future .

Abstract: Natural frequencies are calculated for a short cylindrical shell based on semi-analytical method of transfer matrix, especially considering the structural effects of sealing teeth. The thin wall shell with some sealing teeth can be divided into finite segments where the diameters are different. According to the theory of the state vector expression of a structure cross-section, a first-order ordinary differential equation referring to state vectors of continuous segment sections of a short cylindrical shell is established based on governing equations of thin cylindrical shell. Then a total transfer matrix of the shell with sealing teeth is obtained after producing all the transfer matrices of all the segments. The boundary conditions investigated in the study are free-free, free-clamped and clamped-clamped of the two ends of the shell. The natural frequencies can be solved by precise integration of the differential equation of the whole shell with divided segments. The obtained numerical examples show that the sealing teeth have influence on the frequency values of higher circumferential modes, and they also have influence on the natural frequencies in different boundary conditions. The results by the proposed method are also compared with those of finite element method.

Abstract: The paper presents the structural characteristics of counter flow screen. Pieces of plastic film and sandstones with different friction factors and elasticity coefficients are chosen as the research objects. The motion state and the sorting mechanism of materials in the sorting process are studied. According to the motion analysis on pieces of plastic film and sandstones on counter flow screen, it can be concluded that the materials with different friction factors and elasticity coefficients can all be sorted by counter flow screen. The more difference they have in friction factors and elasticity coefficients, the better sorting performance can be achieved. The selection and computation on the dynamical parameters of counter flow screen is carried out, which provides the theory evidence for the design of new friction sorting equipment and opens up new prospects for the application of counter flow screen.

Abstract: It is well known that the fatigue failure of bolts can affect the performance of rail joint and the safety of train running. In this work, the influence of the bolt torque and radius of rounded root of rail bolt on the fatigue strength of the rail bolt are studied by Finite Element Contact Analysis method. And the influence effects of the wheel impact and temperature force of the rail caused by temperature changed on bolt failure are studied. The results indicate that properly torque and increasing the radius of rounded root rail bolt can reduce the stress concentration at the root of rail bolt and this will improves the fatigue strength and the working life of the rail bolt and rail joint. The repeated temperature force of the rail and wheel impact force are playing an important role in the influencing factors on fatigue failure of the rail joint bolts. Due to this, the two bolts near the rail joints will to be fatigue failure almost earlier than others. That is one of the reasons why the bolts should be preloaded or replaced regularly.

Abstract: The goal of this paper is to form a mathematic model indicating the relationship between the structural parameters of a filter element and its pressure drop. Under study a plait stainless steel filter element used for a hydraulic pipeline filtration system, search for the optimized structural parameters of a filter element used for XYZ-100 lubricating stations and simulate numerically its optimized structural parameters that are worked out theoretically by means of the FLUENT technology of CFD software. Based on the theoretical model, the optimized structural parameters are proved to be feasible through contrasting the theoretical outcome with the simulated outcome.

Abstract: The trench field ring for breakdown voltage of power devices is proposed. The new ring can improve 10% efficiency comparing with conventional field ring. Five parameters of trench field ring for design of trench field ring are analyzed and 2-D devices simulation and process simulations are carried out. The number of field ring, juction depth, distance of field rings, trench width, doping profiled are discussed. The proposed trench field ring was better for higher voltage more than 1000V.

Abstract: This research focused on solving volumetric locking problem of shell structure of incompressible material. Degenerated solid-shell elements are widely applied on curved structure. But, volumetric locking will take place when the structure is made of incompressible material, such as rubber. Due to Poisson’s locking free property of P1-nonconforming element, it is employed to solve volumetric locking problem of shell structure. Furthermore, the study on shell structure is extended to topology optimization design. To verify the volumetric locking free of P1-nonconforming element on shell structure of incompressible material, some structures are studied by different elements. Comparing with the utilization of high order elements to solve volumetric locking problems, P1-nonconforming elements can save calculation time and reduce the numerical cost.

Abstract: Magneto-rheological (MR) damper is a typical non-linear actuator. The nonlinear relationship between the input and the output of MR damper should be characterized accurately in order to produce a required control action supplied by MR damper. The challenges of the conventional parametric model are the time-consuming and the requirement of complex parameter identification for MR damper. In this paper, a non-parametric model of MR damper based on the adaptive neuro-fuzzy system theory is presented to overcome the drawbacks of the conventional parametric model. This non-parametric model is developed by means of two adaptive neural fuzzy sub-systems which are designed to describe the nonlinear relationship in MR damper successfully. One sub-system is used to characterize the dependence of the damping force on velocity and acceleration, the other sub-system is used to characterize the dependence of the damping force level on the control voltage. The proposed non-parametric model is identified by experimental results. Furthermore, the accuracy of the model is investigated and evaluated. The model supplies a key technical support to achieve excellent control performances for semi-active suspension systems with MR dampers in vehicle.