Applied Mechanics and Materials Vols. 401-403

Abstract: In order to remove burrs of soft magnetic ferrite precisely and efficiently, the stand type ultrasonic de-burring machine was designed based on the theory that the ultrasonic wave can produce acceleration. Firstly, the whole plan proposal of the new design was presented. Then the ultrasonic vibrating system, controlling system, the 3D mobile platform were respectively designed in detail. Finally, the design process was verified correctly by the de-burring experiment results.

Abstract: Function design is an important step in the process of product design. This article mainly focuses on process and realization of product function innovation. Function innovation and forecasting method is presented, and the product function innovation process model is proposed. Finally, the heating equipment is taken as an example to validate the effectiveness of the model.

Abstract: Global warming is currently one of the most serious environmental challenges in the world. The increase of CO₂ in the atmosphere is a dominating factor to global warming .O₂ / CO₂ combustion technology is a new generation of clean coal power generation technology^[1],it can directly capture high concentration of CO₂ and make the pollutant resource ,so it is one of the most promising feasible technical to reduce CO₂ emissions ^[2]. Compared with conventional pulverized coal combustion boiler, O₂ / CO₂ combustion technology can be used to produce a CO₂ rich flue gas stream. So physical parameters had a very big change, such as flue gas heat capacity, motion viscosity, prandtl number and so on. Thus they affect the heat transfer characteristics ^[3] inside the furnace.In order to study the heat transfer characteristics of the furnace; this paper established a dynamic mathematical model for the radiation heat transfer progress of the furnace and adequate for control system design.

Abstract: This paper take the impeller of S series airfoil for instance, in view of the complex flow field which is in the condition for the optimum attack angle of design wind velocity with tip vortex, presents a new generating strategy of grid based on controlling gradient method which takes the non-uniform tetrahedral grid with gradient gradual change in the near blade wall flow field. The transition layer grid which is in the development from body-fitted field to the middle of the domain having relatively high density of grid contrast with the far flow field can well capture the size and location of tip vortex, and find that the decay rate of the vorticity magnitude of tip vortex of S series impeller is more quickly than the tip vortex of traditional airfoil impeller. As well as find a fraction of central vortex and tip vortex shaded into each other in the far field and Doppler effect in the downstream. Because the numerical experiment and analysis showed that through controlling gradient change of grid can get high precision of calculating results, can also get S series impeller had higher efficiency in conversion of wind energy contrast with NACA series impeller, so the generating strategy of grid is reasonable and effective.

Abstract: Through case analysis method introduced in this paper using the relation formula of the Pro/E to complete a part fast modeling method, which can greatly improve work efficiency, for beginners will have high reference value.

Abstract: The Copula theory was applied when the reliability in mechanical transmission was difficult to be predicted, the reliability model between gears had been established, the dynamic relationships of mile, relevant parameter and reliability had been established. The model was applied to verify between two gears in transmission of the self-propelled gun, compared with the real situation, the model could provide reference for life and reliability prediction of complex drive system.

Abstract: Reliability failure analysis is extremely important in the manufacturing process of PCB (Printed Circuit Board). In this paper, we use thermal shock test method to analysis the electrical interconnection reliability of PCB in harsh environment. Also taking into account the reliability of PCB is closely related to its design and technology, approaches of technological improvement are proposed. Finally through temperature shock test method, the results show that the reliability of PCB designed with improved technology is enhanced.

Abstract: The induction motor (IM) is important equipment among industries. When voltage sag occurs, both the protective device like reclosure mounted in high voltage transmission and distribution lines and the terminal undervoltage tripping of contactor will make the IM disconnect away from the utility, with its terminal voltage changed from voltage sag to interruption. The IM will continue to operate because of inertia. The first-order dynamic model between slip, load torque and terminal voltage is set up based on IM steady-state equivalent circuit. And the universal analytic functions of slip and critical time are deduced from the model which can be used to evaluate the IM low voltage ride through (LVRT) capability, thus providing reference for the designation of IM.

Abstract: For comprehensive research on the dynamics of U-tube natural circulation evaporator in plant, the modular and lumped parameters method is used to establish the mathematical model of U-tube steam generator. Steam generator is divided into three parts in the model: primary water side, U-tube metal side and secondary water side. Secondary water side includes five modules. Then, the dynamic simulation experiment can be made on the basis of the simulation model. The experiment results consistent with the actual data and the adaptability and rationality of the model are verified.

Abstract: Abstract: During the transportation of the oil which is replaced from stratum by return water with demulsifier, the rheology of the water cut oil must have been affected. In order to study the influence rule of emulsion which contains hydrophilic demulsifier, we don this experiment which tests the different demulsifier using HAAKE Viscotester 550. The testing result showed that for crude oil emulsion, the effects of the factors on the rheological index and demulsifier evaluation index into corresponding relation, this provides the rheological field development significance; Demulsifier could move forward the emulsification diversion point, and the viscosity of the emulsion decreased effectively with different moisture contents. Different structure types of demulsifier have the different influence on viscosity. Finally, we conclude the influence rule of emulsion which provides the daterbase for crude oil heating airtight gathering and transportation technology .