Advanced Materials Research Vol. 662

Abstract: Aiming at the difficulty and low automation in installing slabstone under dry-hanging technology which is heavy and large in size, a slabstone dry-hanging installation robot system was developed. According to the working requirements such as load, installing precision and process, we researched a 6-DOF of series-parallel manipulator, analyzed its structural and completed the inverse solution. The inverse position equation of the robot was derived based on the kinematical theory. Mathematical relation between the Position-Orientation parameters and the direction cosine matrix was established. Experiments show that the robot can achieve slabstone auto- installing, and solve the problems in the dry-hanging installing.

Abstract: In order to establish a flexible squirm pipe robot’s mechanical model and find an appropriate method to improve its moving performance, the working qualifications and dynamic analysis of brake wheels are made. Proceed with the robot's moving mechanism, the squirm principle and mechanical qualifications of the robot’s brake wheels are analyzed, and the model of the robot’s traction is derived. Based on that, the prototype is made. Finally, the validity of the design and theories is verified by experiments.

Abstract: Undertaking the 316L stainless steel as a medical stent material and the coronary stent structure as the research object, ANSYS Workbench12.0 is used to simulate the free expansion process of coronary stent by two expansion methods. Finite element analysis is used to solve such problems as deformation behaviour of the stent, mechanical behaviour as well as nonlinear problems of the stent and balloon interaction during the free expansion process. The simulation results show that the stent and balloon interaction process will appear slip phenomenon, the stent shortening in the axial direction and elongating in the radial direction, and that the arc supporting rod location of the stent is the main area of the maximum stress. These can provide a scientific reference for the next new stent design and optimization.

Abstract: The quality of high speed machining is directly related to dynamic characteristics of spindle-toolholder interface. The paper established normal and tangential interactions of BT spindle-toolholder interface based on finite element contact theory, and analysed free modal in Abaqus/Standard. Then the result was compared with the experimental modal analysis. It shows that the finite element model is effective and could be applied in the future dynamic study of high-speed spindle system.

Abstract: The paper presents numerical investigation of cavitating turbulent flow in a high head Francis turbine runner fitted with splitter blades at part load operation. Analysis was performed by OpenFOAM code. A mixture assumption and a finite rate mass transfer model were introduced. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results show that the volume fraction of water vapor and the pressure uneven distribution on the main blade and splitter blade. It will lead to cavitation and fatigue damage.

Abstract: The paper presents the numerical prediction of sediment erosion on Francis turbine blades using CFD code. The 3-D turbulent particulate-liquid two-phase flow equations are employed in this study. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the sand erosion rate on pressure side is more than on the suction side of the blade. The numerical simulation results are consistent with the real situation.

Abstract: In this paper, a design solution selection methodology for product design is described. The described technique incorporates the customer satisfaction forecasting and design solution risk analysis into the process of evaluating alternatives for systems or sub-systems design solution, which enables the design of products by satisfying customer, technical, schedule, and financial requirements. Also, an additional comparison technique for comparing design solution alternatives is developed. In this technique, pair-wise comparisons are performed to measure the strength of one-to-one relationship between optimal solution and alternatives solution. An illustrative example demonstrates the application of our methodology to the design of a motorcycle system.

Abstract: The permanent magnet lifting chuck has been designed. The working principle was proposed. The fuzzy expert system of lifting chuck magnetic circuit was developed. Meanwhile, the perfect self-acting driving system has been invented. Industry prototypes were manufactured, and they verified that the designed lifting permanent magnetic chuck was feasible.

Abstract: Spline finite strip is the common theoretical analysis method to sheet materials. On the mechanism of cold forming, using spline finite strip theory, characteristic line connection and characteristic finite strip are to build on the reasonableness. Ignored a number of uncertainties, avoided "massive" data, this model simplifies the boundary conditions, improving the system agility. The qualitative factors which are difficult to establish mathematical expression in forming, and the constraint conditions to form model, were tranformed into information description. Combing with specialist experience, solving task system of multi-Agent was established. Then, the dynamic task can be solved by intelligent Agent. This work can provide theoretical guidance for research to sheet materials forming.

Abstract: In order to examine whether the wheel hub meet the security requirement during its design stage, the 3D model of a wheel hub was built by UG software, on which strength test of the wheel hub was proceeded based on the simulation experimental conditions , and used finite element method to analyse the wheel hub strength. The analysis results are the basis for modifying and lightening wheel hub.The study demostrates that test simulation and analysis to the wheel hub by computer technology can overcome the shortcomings of traditional experience analogy method in which the strength test only can be done after the product is produced. The method improves working efficiency，shortens the product development cycle, reduces costs.