Applied Mechanics and Materials Vols. 635-637

Abstract: With the development of science and technology and the progress of human society,We gradually know that survival environment is worsening,the further development of the economy has been restricted.These problems directly affect the reproduction of human civilization,So our country put forward the strategy of sustainable development.The concept of green packaging design is adapted to the demand of the times,in order to explore the application of the green idea in the packaging design.Green packaging design needs to consider packaging materials,this will affect the packaging cost.The 60% ~ 80% of the packaging cost have been confirmed in the product design stage.Green packaging structure design should be considered,the structure of reasonable design of packaging, not only can reduce cost, but also reduce the adverse impact on the environment.When we need to use the least amount of packaging materials,a sphere is the best choice.The height of the cylinder is equal to the radius of 2 times through calculation,Its surface area is smallest.Green packaging, therefore, on the one hand, can avoid the waste of resources,let our design work can be harmonious with our living environment.

Abstract: To simplify the model of rotating cylindrical shell, the static forces are neglected and the vibration equations are established. Transfer matrix method is used to solve the equations and the example shows that the simplified model has little effect on the result. So the simplified model can be used in complex structures such as multilayer and multidiameter shell.

Abstract: In view of poor accuracy of an overhead weapon station’s automatic firing, analyze the main vibration parameters affected the projectile dispersion, establish the vibration characteristic optimization model based on dynamic stability concept, and sensitivity analysis. Through optimization design of weapon station structure parameters, optimize the vibration characteristics and improve the accuracy of automatic firing. This method has certain reference value for structural modifications of the weapon station.

Abstract: This paper aims to develop a new systematic analysis model to predict the wear of ball screw in stabilization condition. In order to investigate the wear behavior between the ball and raceway, a proper contact mechanics model should be established. Then, the wear model of ball screw based on Archard will be proposed and calculated by substituting the ball screw parameters. It has been proved that the effectiveness of the wear model on ball screw is verified through experiments in a specialized test system, which provides the theory basis of reasonably reducing the wear and improving the mechanical efficiency of a ball screw.

Abstract: In the working process of the traditional hydraulic excavator, the potential energy could not be properly applied in the course of boom-down, whereas the boom requires additional kinetic energy to rise, resulting in a waste of energy, heating up the system, reducing the service life of the machine. As a solution to this problem, the paper proposes the balance hydraulic excavator, adhering to the energy-saving principle of mechanical design, on the basis of which, turning the traditional hydraulic excavator’s fixed weight into a sliding weight and fuel tank, meanwhile, connecting the sliding weight fuel tank with the boom fuel tank, which constitutes the machinery - hydraulic hybrid balance system to the effect of saving the system energy, improving the overall stability and reliability.

Abstract: This paper presents the backtracking search optimization algorithm with low-discrepancy sequences to solve mechanical design optimization problems involving problem-specific constraints and many different variables. Similar to other evolutionary algorithms, backtracking search optimization algorithm is sensitive to the initial population. Generally speaking, since there is no information about the optimization problem, the initial population should be created uniformly. The low-discrepancy sequences are employed to increase the uniformity of the initial population. The benchmark problems widely used in the literature of mechanical design optimization are used to evaluate the performance of the presented algorithm. Results show that the proposed algorithm is effective and efficient for solving the mechanical design optimization problems considered.

Abstract: Based on the Sobol’ theory, Hamma and Saltelli indicator system, the path parameters were divided into the different subsets for the vibration transfer path systems with random paths in this paper. The object function was constructed and decomposed, thus the global sensitivity based on variances was formed. The first-order and total sensitivities of various parameter subsets were calculated using Monte-Carlo simulation method combined with Latin hypercube sampling technique. Through the analysis example, the way is feasible to analyze the interaction of paths or path parameters in the vibration transfer path systems with uncertainty.

Abstract: With elastic modulus perturbation parameter of blade as mistuned parameter, a parameter identification method of mistuned blades is presented based on static frequency test , bisection method and finite element method. Take mistuned blades of the compressor as an example,the mistuned parameter of blades are identified. The identification results show that this method is high precision and fast speed.

Abstract: The operational principle and composition of the new automatic lift pump and valve is shown, and concerned formulas are deduced on the basis of the analysis of experimental data.

Abstract: Based on the needle selection principle and requirements for hybrid magnetic type of driving knitting needles, this paper puts forward the mechanical model for the knitting needles of magnetic suspension drive mode. This paper analyzes the force model of the knitting needle by establishing the relationship between the magnetic force and the air gap. It also researches stress and strain for the knitting needle by using the finite element method. All these results will provide guidance for the optimal design of the knitting needle and parameters design of the key components like the needle cylinder and so on, at the same time these results will also provide a theoretical basis for the study of coupling mechanism for the knitting needle.