Applied Mechanics and Materials Vols. 184-185

Abstract: This paper analyses the reasons and influencing factors of resistance during the pipe transportation of dense paste. Taking coal slime for example, the experiment is conducted on pressure pipe rheological and resistance characteristics test system. It studies how three key factors (the concentration, flow rate, and diameter) influence the dense paste's transportation resistance loss. The test indicates the linear relationship between transportation resistance loss with average flow rate, the power law relationship with pipe diameter, and the exponential relationship with volume concentration. This study provides test foundation and analytical method for establishing a typical dense paste pipe transportation resistance loss computation model.

Abstract: Aiming at optimal design of the hardcore of meat skewering equipment — material forming mold and object-carrying table, the author insights into the stress deformation regularity of soft and solid material with compression test for fresh lean pork based on the analysis of fundamental feature of soft solid material and macroscopical observation of changes in form under different pressures. Through the algorithm of Dichotomy Method with which four tangent sections of arc are connected to fit ellipse, a mathematical mold is constructed to fit the area difference and to optimize the solution with parameters of surface which is consisted of multiple tangent sections of arcs and AutoCAD to ensure the correctness through drawing the surface diagram for the detailed parameters of the cavity.

Abstract: The active vibration control of beam is researched by using piezoelectric constrained damping structure. The energy characteristic of each layer for the piezoelectric smart constrained damping beam is completely expressed based on the finite element method and the damping layer shearing movement relationship is described by ADF model. Then the structure mechanics model for dynamic parameters is established. Applying displacement error signal, an adaptive filter controller is designed. Under the different outside disturbance, structure vibration responses with active control are analyzed. It shows that the piezoelectric smart constrained damping structure can have good control performance for the active and it has a good engineering prospects.

Abstract: The offset optimization is one of the key elements of designing cam mechanisms. This paper presents the mechanical model of a disc cam mechanism with an offset translating negative radius roller follower and deduces the efficiency expression. Then it proposes pressure angle and efficiency integration as the evaluation index of pressure angle and efficiency respectively. Furthermore, the optimal offset is derived according to the index. Finally, an example is provided to illustrate the method to obtaine the optimal offset.

Abstract: Based on the braking system of a tracked vehicle, a method for co-simulation is introduced with dynamic simulation software ADAMS and multidisciplinary dynamic simulation software EASY5. By designing software interface, dynamic data exchange between the two models is achieved, and the simulation is carried out about the impact on a tracked vehicle brake performance with accumulator volume and gas-filled pressure. The simulation result shows that a seamless connection between the virtual prototype model and hydraulic system model is realized.

Abstract: Abstract. In this paper, the strength reliability and parameter sensitivity analysis of a missile airfoil structure are researched. For checking strength of the missile airfoil structure before reliability analysis, stress distribution is analyzed by MSC.Nastran. Owing to the fact that machining deviation and design tolerance result in size dispersion, thickness of missile airfoil skin, thickness of ribs, length of airfoil and length of fork are considered as random variables. Based on certain analysis, the strength reliability and parameter sensitivity of the missile airfoil structure are analyzed by the fourth moment method. The reliability analysis illustrates that the strength failure probability of the missile airfoil structure is 0.01286 and the results of sensitivity reveal that the thickness of ribs is the main factor which influence on the strength reliability of airfoil structure.

Abstract: Put forward a method that use scatter points which got in different places to measure the involution cylindrical gears, give a mathematical model that use the discrete points to sure the total deviation of gear tooth profile. The experience results show that this way is of high precision in measurement points, measurement an error data processing less intervention, etc.

Abstract: According to the purpose and requirements of a virtual test, the complex mechanism of the combine harvester was abstracted and simplified to some extent during modeling, but in order to guarantee the closeness between simulation result and the reality, attention was paid to keeping the total mass of all components close to the actual mass of the combine harvester and reducing workload during modeling. The vibration test of the cleaning operation includes horizontal vibration and vertical vibration. The test conditions are that: the combine harvester is still and has no load and only the engine runs, or the engine and the cleaning component run simultaneously. To guarantee the extractions are thrown out of the machine in the rear end of the screen, the backward slip of the extractions is greater than forward slip. The simulation result satisfactorily reflects the real situation and is same as theoretical analysis. The result indicates the virtual test and the real test are consistent.

Abstract: This paper investigates the synchronization of chaotic and hyperchaotic systems, and proposes a simple and universal method for chaos synchronization through investigating the dynamical behavior of the chaotic error system. In comparison with previous methods, the present controllers are simpler than the existing results. Especially, for some class of three dimensional chaotic systems, the obtained controllers in this paper contain single state feedback. Numerical simulations verify the effectiveness and correctness of the proposed method.

Abstract: An environment-friendly material MgO-ZrO2 brick which is hoped to substitute for MgO-Cr2O3 brick was investigated. The using effects of MgO-ZrO2 brick and MgO-Cr2O3 brick were compared by rotating slag attacking method whose environment is similar to the environment in RH degasser. It indicates that the corrosion resistance performance of MgO-ZrO2 brick is better than that of MgO-Cr2O3 brick. Due to the effect of molten steel, slag and oxygen, Fe being oxidized to FeO or Fe2O3 at high temperature 1900K will produce volume expansion which results in MgO-Cr2O3 brick being cracked. At the same time, Cr2O3 will be decomposed to CrO3 gas, which will be evaporated seriously by the airflow and lead to MgO-Cr2O3 brick structural loosen and deterioration, ultimately. While the activity of oxygen dissolved molten steel is extremely low and ZrO2 is stable in the rotary kiln at 1900K. Furthermore, ZrO2 will react rapidly with CaO and its product CaZrO3 will form dense layer to prevent MgO-ZrO2 brick from being corroded. Therefore, trial production of MgO-ZrO2 brick applied for RH degasser is recommended.