Applied Mechanics and Materials Vols. 397-400

Abstract: Laser Doppler Velocimetry is an important flow diagnostic methodology used in modern day fluid flow investigations. The present paper describes the design and manufacturing aspects of a novel fibre optic LASER Doppler probe head intended for three dimensional measurements in a complex flow field. The paper particularly concentrates on the tight tolerances required of the various components associated with the probe head to achieve the desired measurement volume. Keywords: Fibre Optic, Laser Doppler, Velocimetry, three-dimensional, complex flow field

Abstract: The paper combined with engineering background, Selecting the Pressing gear of CNC crushing Machine Steady Support Body as starting point for Optimization modeling, Analyzed the simple conditions theoretical physical model of Support Body. Reasonably we selected design variables, optimized the Support Body, and obtained relevant data. And analyzed the results, to check the accuracy of the optimize results through the individual histogram map.

Abstract: Aiming at present method deficiency of getting loader oil-cylinder external load, this paper reserached the determination method of loader steering-cylinder external load change characteristic. After establishing the mathematic model of steering cylinder external load, we actually tested and processed oil pressure and piston displacement when loader shovelling semihumid soil, and obtained the change courses of piston displacement and oil pressures of rodless and rod chamber under a single typical operation cycle. In the paper, we applied matlab to fit oil pressure and piston displacement at different operation segments of the obtained single typical operation cycle, and by the programming process, we acquired the external load waveforms of steering cylinder different operation segments, after merging each segment waveform with nsoft software, we obtained the change characteristic curve of steering cylinder external load when loader shovelling semihumid soil. The analysis shows that the determined change characteristic of steering cylinder external load was consistent with the actual condition.

Abstract: In order to ensure the necessary economy and power performance indexes of car, it was necessary to configurate reasonable transmission gear and transmission ratio. Taking 6 tons truck as an example, two methods were designed according to geometric progression and offset geometric transmission ratio. The results show that the method of bias geometric distribution ratio is superior to the method of geometric distribution.

Abstract: According to the high speed bearing failure problem caused by the high temperature, finite element model of high-speed hybrid ceramic angular contact ball bearing is established in this paper. Quantity of heat and heat transfer coefficient are calculated by using the heat transfer and thermodynamics theory, which are boundary condition for the temperature field simulation analysis of ball bearing. The temperature distribution of bearing is obtained when bearing speed is 12000rad/min. The results can provide a theoretical foundation for lubrication cooling system controlling temperature.

Abstract: Heat generation and deformation of bearing are key factors that influence the rigidity and machining accuracy of the high-speed precision spindle system. Based on heat transfer and thermodynamics, the finite element model of angular contact ball bearing is established for thermal deformation. The contact stress and thermal deformation are analyzed and obtained at a speed of . The results show that the maximum contact stress and thermal deflection appeared at contact region, which is in accordance with actual status. The results provide the reference and the theory basis for research into thermal deformation of bearing.

Abstract: The matter-element model for the accuracy evaluation of the machining center is established based on extenics theory, the accuracy evaluation indexes of machining cente are made of multiple elements. The relational degree is calculated by introducing the relational function in the extension set theory, and the weights of evaluation indexes are defined with AHP (the analytic hierarchy process), so the awaiting evaluation machining center is determined though the accuracy grade. A type of machining center as an example is studied the practical application of the proposed method, the result is reasonable and shows that the method possesses a certain practicability.

Abstract: According to the needs of the scheme design of on the modular vertical lathe, the requirements of the customers and the tasks of the design are analyzed. The selection of the main technical parameters in the primary scheme design on the vertical lathe is specified. Take the main transmission system as an example; the process of the general design scheme is described.

Abstract: This article puts the automatic CNC grooving machine as the research object, which oriented by the enterprise's actual demands, and designs the product structure. Furthermore, the paper applies UG/NX 3d modeling and motion simulation to the product. Verify the machining accuracy through experimental study, on this basis, carry through commissioning and improvement to grooving machine, thus it is concluded that the design is feasible.

Abstract: A small and light lifting equipment used to install and overhaul in wind turbine is introduced. Thereinto, load: 500 kg, lifting height: 70 m, lifting speed: 8-12 m/min, slewing radius: 2 m. The equipment and auxiliary materials are shipped to the cabin through the rotation of the crane jib. And the equipment can be also used to assembly plants in mechanical processing and transport materials in warehouse. According to the design and calculation of slewing arms structure, the equipment can meet the requirements of domestic 1.5 MW wind turbine.