Applied Mechanics and Materials Vols. 201-202

Abstract: In order to meet the needs for the precise polishing of free-form surfaces, a new compliant polishing tool system was designed based on a magnetorheological torque servo (MRT), and integrated into a CNC milling machine. Through analysis, it was pointed out that the key factor affecting the polishing quality of this system is the stability of the system. By means of the 3D geometric modeling software ProE, the finite element analysis software ANSYS, and the dynamic simulation software ADAMS, the rigid-flexible mixed model of the system was established and the stability of the polishing pressure and tool position was numerically analyzed.

Abstract: In order to reduce the risks and uncertainties in conceptual design of submarine rescue vehicle (SRV), the paper proposed a risk-based conceptual design method, which consisted of three focus areas: problem setup, risk assessment, risk mitigation and decision support. Conventional risk assessment tools (e.g. probability risk assessment) were not suited for initial design because of lack of data, and a safety analysis model using fuzzy-logic approach employing fuzzy IF-THEN rules was introduced to carry out risk analysis in conceptual design. Subsequently, it was investigated that the main risky factors which influenced system risk in initial design were technology level of SRV, safety of SRV, task complexity, investment and repayment. And then a risk analysis model for submarine rescue vehicle was introduced. Lastly a case was studied to demonstrate the application of the model, and the results showed that it was an effective way to reduce the risks and uncertainties in conceptual design process.

Abstract: The experimental study was carried out on the cyclic loading behaviors of impaired reinforced concrete beams strengthening with prestressed CFRP sheets. Eight beams in four groups with or without strengthening with prestressed CFRP sheets were tested, in which one or two layers of prestressed CFRP sheet were bonded on the bottom surface of the beams. Based on the analyses of test results, the flexural stiffness and ultimate resistance under cyclic load were effectively enhanced for the strengthened beams with the increasing layers of CFRP sheet, but the ductility of their mid-span deflection was reduced.

Abstract: As there are the errors during the manufacturing and assembling of horizontal driving machine (HDM). The exceptional knocking noise is generated during some products running. The failure rate of product quality is rising as well. The forward and reverse driving noise of HDM was tested and analyzed. The pictures was collected by universal tool microscope. The results show that hot runner is not smooth enough to reduce transferring pressure and increase the shrinkage of worm pouring gate, which lead to slight conical degree of product and pitch deviation at worm pouring gate. As the pitch makes worm inset slightly worm gear when clockwise rotating, the noise and vibration was produced consequently in this direction. The proposals were given, such as strengthening the maintenance of hot runners, controlling and inspecting product conical degree, and optimizing HDM mould and increasing its accuracy, and so on.

Abstract: For the short life of hot work die in enterprise directly caused problems the waste of resources and the rising cost of production. Based on studying the biological prototype of crack-resistance of plant lamina and found that surface thermal fatigue crack is one of the main factors affecting the service life of hot work mould, it is put forward thoughts about the local bionic laser melting on mould surface to block cracks. Different from the traditional mould surface integral laser transformation hardening (LTH) technology, using laser melting simulating plant lamina to block cracks on the partial surface of mold, life of bionic strengthened die is improved within 1~1.5 times. Experiment results show that a new method is provided to improve the service life of casting mould and promoting this technology will bring significant economic benefits for the mould industry.

Abstract: Parametric design has become effective means of the initial or dynamic design with its powerful sketch design and dimension driven function. When the structure of the steam injector is redesigned, its sizes would also change, but the topology information did not change, so steam injector may be parameterized drawing by dimension driven.In this paper, parametric thought of the size driving would be used in parts drawing of steam injector, and the parts drawings assembly method would be implemented in the generation of assembly drawings.

Abstract: Traditional energy saving methods for engineering vehicle cannot raise the effect on a large scale if there are no major technology breakthrough. Hybrid system has the potential of improving fuel economy by operating the engine in an optimum efficiency range and it has been successfully applied in engineering vehicles. So equipping engineering vehicle with the hybrid system provides a new way to achieve energy savings. Simulation results of vehicles based on backward modelling shows that the energy control strategy can achieve a variety of reasonable operating mode switching and meet the vehicle at power.

Abstract: The influence of internal waves is very important in the Engineering Analysis, Design and Optimization. To study the internal wave properties, we model a two-layer fluid and generalize to multiple layers. In a two-layer fluid with the upper layer having a free surface, there exist two modes of waves propagating due to the free surface and the interface. This is due to the density difference in the vertical direction of the water, due to the variation in salinity and temperature where waves from underwater structures are of importance. In this case the fluid is assumed to be non viscous, incompressible and the flow is non rotational. On the other hand, there is need for appropriate Green functions to analyze these properties. In this paper, we use the three dimensional Green functions for a stationary oscillating source to study the internal wave characteristics. Some of the behavior studied in this work includes effects of internal waves on the surface and internal wave amplitudes. Further, an investigation of the influence of internal waves on the wave length, frequency and period is made.

Abstract: This paper presents a mathematical model to simulate the actuation of a multilayer metallic strip. The model computes the radius of curvature of the actuator when it curls because of difference in thermal coefficient of the different metals used in the strip. The mathematical model for simulating the radius of curvature is based on the earlier work by Timoshenko [4], and Jianyu Fu[5]. The radius of curvature computed is used to calculate the voltage to uncurl the actuator. Numerical experiments were performed on the model and the trends were found to be in agreement with the experimental data.

Abstract: The pressing chamber is the heart of the screw press, it forms the drainage barrel and has to contain the operating forces of the press. As press casing is an integral part of pressing chamber, the strength of the press casing ensures normal operation of the press. The mechanical models of pressing chamber of the ZX10 type press created in MATLAB 7.0 for linear programming, and the 3D model of the press casing created in UG NX4.0 software were imported into ANSYS 9.0 software and a linear static finite element analysis was performed. The visual deflection patterns the part experiences under "real world" loading conditions were obtained so as to complete the security check of strength.