Advanced Materials Research Vols. 199-200

Abstract: A new type of variable topology parallel tire building drum mechanism was presented in this paper and the solid model of the mechanism was established. The elastic dynamics model has been established by the condition of displacement and power which the rigid connected with elastic body. The model of variable topology parallel mechanism was imported into the ADAMS and analyzed the elastic dynamic simulation of the mechanism.

Abstract: Due to shearer drum suffers a very complex load，the traditional theoretical algorithm of cutting resistance is difficult to satisfy the analysis and design of shearer, and the load features of various conditions is hard to obtain with experimental methods. The study demonstrates that the time series of cutting resistance is of chaotic characteristics, and the cutting time series identified by the C-C method contains the characteristic parameters of the cutting power system. Based on the experimental and theoretical studies, the mathematical model of load of chaotic characteristics is established in the work process of drum, and the simulation results and characteristic quantities of actual load spectrum of shearer show the excellent agreement, which satisfy the theoretical calculation of quantitative load of shearer and provide certain theoretical basis for the analysis and design of shearer.

Abstract: High strength and water stability earth consolidator (HEC) is a kind of hydraulic cementing material. In order to get mechanics and contact blast capability of HEC concrete, flexural and compressive strength parameters were obtained, and the model tests were carried out on HEC concrete under contact blast. The tests above show that HEC concrete has good mechanics and anti-blast capability is about half a time higher than that of normal C30 concrete.

Abstract: Structural design of ships against collision requires prediction of the extent of damage to stiffened plates subjected to impact. In ship structures, stiffened plates are furnished with vertical or horizontal stiffeners to sustain conventional loads such as shearing, bending and local buckling. The consideration of collision in ship structural design is especially important for tankers where accidents may cause serious environmental pollution. In predicting the extent of collision damage, FE modeling of stiffened plates using ABAQUS software is applied to demonstrate different collision scenario. Typical stiffened plates of tankers in service with different configurations of stiffeners are used to examine absorbed energy in each case. The aim of this paper is to examine the stiffener shape that absorbs more deformation energy.

Abstract: Flail knife is one consumable part of aluminum scrap impact crusher made in Germany. In order to lower production cost, localized production of flail knife has been researched. Flail knife in steel 42CrMo has been developed instead of that of Germany. In course of using, neck of the self-developed flail knife has been broke up and fractured. For seeking the reason of failure, microstructure and mechanical properties of new flail knife has been analyzed, and force condition has been calculated by finite element analysis, heat treatment process and installation technology has been investigated. The reason of failure in flail knife has been summarized, and the heat treatment process optimized has been designed and took good effect.

Abstract: The printing quality is decided by the ink system, which is heavy and complicated in offset press. Structure optimization and parameter modification is the key step of seeking better performance in the ink system. In this paper, the ink system of modern offset press was the research object, seeking the discrepancy of different structures and parameters. The surfaces of ink rollers and cylinders were discreted by computer simulation,based on this,established the math model of steady time in batch and continuous ink feeding system, then analysised the feeding system and vibration system. The simulation result indicates that the ink feeding system, the way of vibrator oscillation, plate coverage have great influence on the dynamic property. In batch ink feeding system, the property of ink system would be improved by increasing ductor roller swing frequency, and approached to continuous ink feeding system. On the machine with adjustable ductor roller swing frequency, the steady time would be reduced by regulating ductor roller swing frequency, improved efficiency with reducing paper wasting.

Abstract: To analyze the relationship of brake performances and its influence factors, a kind of tire drum test-bed was designed. The gradation principle of flywheels was proposed based on the double multiplication method and an inertial system with eight steps of flywheels was put forward. The inertia-mass of tire load ranging 400 from 5000 kilograms was divided into 256 levels with the accuracy of ±10 kilograms. The dynamics simulation model was built using SOLIDWORKS and ADAMS. The program of acceleration and brake testing were schemed. The feasibility and accuracy of design methodology of test-bed inertial system were verified by the comparison analysis of simulation and road test. The accurate matching between the moment of inertia of test-bed inertial system and tire load was realized.

Abstract: In this paper, we initially inspected the carbon storage changes of wood materials in manufacturing process combined energy consumption and material loss of wood materials in manufacturing process, analysed carbon sequestration potential of wood materials, and demonstrated the role of using wood in reducing CO₂ emission and mitigating climate warming.

Abstract: In this paper, the contact force control of a constrained one-link flexible arm is fully investigated using a linear distributed parameter model including the internal damping of Kelvin-Voight type. To overcome the inherent limitations caused by the non-minimum phase nature of the noncollocation of the joint torque input and the contact force output, a minimum phase transfer function is deduced by using the feedback and the output redefinition. A PD controller is then designed to accomplish the regulation of the contact force. Therefore, asymptotic tracking of a desired contact force trajectory with internal stability can be achieved. With the infinite product of transcendental functions, exact solutions of the noncollocated infinite-dimensional closed-loop force control system can be obtained so that it is free from spillover problems with stability robustness to parameter uncertainties. Numerical simulations are provided to verify the effectiveness of the proposed approach.

Abstract: The article puts forward a method for calculating the arresting force of carrier aircraft in the case the aircraft meets the cable off-center and the aircraft motion is unsymmetrical. The condition under which the hook will or will not slip on the cable is considered. Based on a great deal of numerical results, the article analyzed the impact of unsymmetrical motion and off-center on landing dynamics of carrier aircraft.