Applied Mechanics and Materials Vols. 121-126

Abstract: To determine the efficiency, load-bearing capacity and fatigue life of beveloid gears with intersecting axes, we design a mechanical gear test bed with closed power flow. To test the quality of its structure and predict its overall performance, we establish a three-dimensional solid model for various components based on the design parameters and adopt the technology of virtual prototyping simulation to conduct kinematics simulation on it. Then observe and verify the interactive kinematic situation of each component. Moreover, the finite element method is also utilized to carry out structural mechanics and dynamics analysis on some key components. The results indicate that the test bed can achieve the desired functionality, and the static and dynamic performance of some key components can also satisfy us.

Abstract: With more and more applications of manufacturing resource in networked manufacturing, material supplier evaluation and selection will become increasingly important. In the paper, the evaluation architecture of material supplier selection is introduced. Then, material supplier group decision making model is discussed. Lastly, multi-attribute group decision making for aviation manufacturing enterprise material supplier is verified based on fuzzy comprehension assessment by an illustration.

Abstract: The energy storage technology is playing an important role in improving power grid stability. Aiming to the randomness and intermittent characteristics of wind power generation, the paper proposed a scheme of mechanical elastic storage energy and power generation system based on flat spiral spring. The flat spiral spring, which is the core component in the system, is selected as the research object, and the mechanical model and the finite element model is created. The geometric parameters of spring are determined. The maximum deformation and the stress distribution of spring are obtained. Moreover, the modal analysis of spring is carried out and the natural frequencies and modes of vibration of first 20 orders are obtained. The relationship between the natural frequency and deformation is also analyzed. All the results in this paper provide a strong basis for the optimization design of spring and the calculation of energy density.

Abstract: Fracture problem about anisotropic composite plate of curved crack is researched with the help of appropriate conformal mapping. The crack curve is transformed into a unit circle by the quoted conformal mapping function. Based on the stress boundary conditions, the special stress function is found and the expressions for the stress field and the stress intensity factor near the parabolic crack tip are obtained.

Abstract: This study was to prepare polycaprolactone (PCL) nanoparticles. The biodegradable PCL was used as the carrier, and Azithromycin (AZM) was used as the model drug. AZM-PCL nanoparticles (AZM-PCL-NPS) were prepared by desolvation method. The effect of preparation condition: concentration of PCL, molecular weight of PCL, organic solvents, dosage ratio and so on, were specially noted and compared. A homogeneous size distribution and good dispersion were observed, the average diameter was around 70~400 nm, and the distribution index was 0.036~0.136. The drug loading reached 27.69 %, and the efficiency of encapsulation reached as high as 93.25%. The results were better than the other similar researches, this preparation way was successful.

Abstract: Based on the analysis of several main evaluation index systems of regional science and technology (S&T) progress in-country and overseas, and refer to the idea of system dynamics and balanced scorecard, this paper explored the causality and dynamical structure of subjective and factor in index systems of regional S&T progress, probed its rules and relationship. After examined and reconstruction the statistical monitoring index system of S&T progress designed by Ministry of S&T in China, this paper putted forward a new framework of evaluation index system of regional S&T progress.

Abstract: For the machine tool with complex forming motion, there is not accurate corresponding relationship between the existing criterion on precision design and the machining precision of workpiece. This article proposes a design scheme on machine tool precision based on machining precision of Workpiece. In this scheme, the first work is to complete the precision distribution and inspection from the workpiece to various component parts of technology system and achieve the total output precision of machine tool under the specified machining precision. This article serves YK3610 gear hobber as the example to describe the error model of system and basic application method in this work.

Abstract: A test bed of closed-end mechanical beveloid gear with intersecting axes is designed to measure various parameters. In order to analyze the reasonableness of the structural design and test the performance of the test bed, a three-dimensional solid simulation model of the test bed is set up first with virtual simulation technology to analyze motion characteristics of test-bed and modal analysis to analyze the vibration characteristics of the key components. Simulation test obtains the vibration mode of the test gear box and drive gear box, providing a useful result for the optimization of the test bed. This solves some problems such as that a common test bed cannot test gear with intersecting axis and must have the same test pair gear, and inaccuracies of measuring transmission efficiency.

Abstract: Stirring blades are the most important part of the reactor. Blades transmit the mechanical energy to the liquid through self-rotation, thus generating high degree turbulences in neighboring areas, and forcing all the liquid to flow inside the tank on a certain route for recycling. This study analyzed the speed deviation and turbulence intensity inside the reactor in case of two or four propeller blades at 45 degree forward, 45 degree backward, or at no deflection angle to explore the impact of different revolving speeds on the flow field inside the reactor. Results suggested that when the blade at positive deflection angle should be applied to generate larger turbulence intensity in the lower flow field to more easily mix relatively weighty particles or quality dispersion.

Abstract: Proceeding from the industrial design, this paper proposed the concept of product form gene with combining the product form and product style, and researched on the extraction of product form gene based on constraint style. It explained how to express product form gene based on style constraints, and construct the description model of product style semantic. This paper using analytic hierarchy process and semantic differential method to extract product gene, and take the real example to illustrate and validate, thereby providing a certain methodology direction for extraction of product form gene.