Advanced Materials Research Vols. 690-693

Abstract: This paper explored a single-machine scheduling deterioration jobs with multi-maintenance activities. The non-resumable case and simple linear deterioration effect were taken into account as well. We assumed that after a maintenance activity, the machine will revert to its initial condition and the deterioration effect will start anew. The objective was to minimize the makespan in the system. The problem was proven to be NP-hard in the strong sense. Therefore, a heuristic and a lower bound were introduced and tested numerically. Computational results showed that the proposed algorithm performed well.

Abstract: By establishing a diffusion model, the solute distribution is investigated during the growth of eutectic phase from the binary melt on the primary phase. Based on the eutectic reaction conditions, reasonable assumptions are carried out to build the partial differential equation. After the determination of the initial and boundary conditions, the analytical solutions have been derived from the method of variables separation. The solute distribution ahead of interface and the influence of this distribution on the growth rate of heteroepitaxial phase are discussed.

Abstract: As final component of coextrusion system in polymer industry to produce product with multi-layer different materials, the coextrusion-die can be regarded as the most important determinant that can influence product quality directly. For design of die-cave that can make uniform pressure and speed distribution for different materials, geometry structure of die-cave and rheology performances of materials must be taken into consideration. In order to reduce the influence of operation uncertainty of polymer extrusion, damping block can be used to make adjustment for flowing speed of different materials. In this paper, a finite element method based simulation is made to analyze the impact of the damping-block to the uniformity of coextrusion flowing. With the simulation result, control methods for coextrusion quality are discussed for damping-block design and operation condition settings.

Abstract: It is significant to study the dynamic characteristics of the mechanical system. In order to prevent accidents such as resonance and self-excited shock, modal analysis of the mechanical systems should be analyzed. The mode shape of gears was analyzed to improving the design security. The sleeve, the planet gears and the internal gear of the motor were simulated. All order natural frequency, the mode shape of the motor was obtained. Research shows that motor running is smooth when the frequency is less than 4230Hz.

Abstract: In order to study the influence of surface error on optical properties for optical part after machining, this paper takes a piece of ring curved lens with aperture D=2mm as an example. When analyzing the influence of surface error on optical properties, it employs the evaluation indexes i.e. wavefront aberration, point spread function and modulation transfer function. The study results show that with the increment of surface error, the value of wavefront aberration increases. Plus, the light of outer loop on the image plane is more obvious and its energy increases, however, the energy in the center range decreases. Moreover, the capacity of information storage decreases and also the image quality decreases.

Abstract: According to the hypoid gear tooth surface forming principle, a generating-line will be formed in round-plane while a cone and its tangent circle plane do pure rolling, and the hypoid gear is cutting according to the motion equation as hypoid gears generating-line. to tools shape. The milling processing equation of the hypoid left-hand gear tooth surface on the right side gear tooth surface and on the left side gear tooth surface.There are a detailed description of the adjusting-tool , cutting out from ends, dividing, cycle cutting the whole process. The above method can realizes hypoid gearwheel right tooth surface processing.

Abstract: According to the brake characteristics of in-wheel motor drive electric vehicles, and basing on threshold control method, we describe one kind of composite ABS control theory about electric motor ABS combined with hydraulic friction ABS, and establish a co-simulation vehicle model. The composite ABS control method is a control method that the electric motor ABS control works together with the hydraulic ABS control. Both of the two modes of ABS control logic were using logic threshold control method. The model of the in-wheel motor drive electric vehicle was established with AMESim, and the model of the composite ABS controller was built with Simulink. The control performance of composite ABS in different braking strength and different road friction coefficients is simulated. Co-simulation was carried out. Through analysis, a number of parameters curves were obtained. It proves that the composite ABS control method for in-wheel motor drive electric vehicles can effectively control the slip rate, and ensure braking stability.

Abstract: According to the requirements of drive shaft, finite element analysis software SAMCEF was adopted in the simulation analysis of Carbon Fiber Reinforced Plastic (CFRP) tube which was the main structure of a CFRP drive shaft, in order to determine the parameters such as fiber orientation angles, number of plies, percentages of fiber with different angles, and stacking sequences. In this paper, the joint between CFRP tube and metal parts was designed. Specimens were manufactured and experiments were carried out. In conclusion, the results of experiments suggested that the simulation analysis predicted well the performances of the designed drive shaft.

Abstract: In this paper, we establish the finite element (FEM) and boundary element (BEM) models of a submarine section, and study the underwater sound radiation field of three different non-pressure shells made of steel, steel with anechoic tile, and the functionally graded materials (FGM) separately using a method combining of FEM and BEM . Research shows that the combination of FEM and BEM can address the acoustic radiation calculation problem of FGM, and in comparison with steel and anechoic tile laying submarine section, the weight of FGM non-pressure shell reduces 1600kg, and the sound radiation power decreases 4db and 2.5db respectively, thus having better performance in vibration and noise reduction.

Abstract: Opening mode fractures in multilayer sedimentary rock often are periodically distributed with fracture spacing scaled to the thickness of the fractured layer. In this paper, based on Rock Failure Process Analysis Code RFPA2D, a three layer model with a central layer and with the different thickness top and bottom layer, progressive formation in multilayer sedimentary rock at fracture saturation in unsymmetrical case is simulated. We investigate the change of the critical fracture spacing to layer thickness ratio as a function of the thickness of the top layer where the bottom layers is much thicker (5 times) than the fractured layer called the unsymmetrical case, in this unsymmetrical case, fracture saturation is simulated. By numerical simulation of RFPA2D, the critical spacing to layer thickness ratio decreases and tend to the same constant value as the thickness of the top layer increases. Numerical simulation shown that for the unsymmetrical case, if the adjacent layers are thicker than 1.5 times the thickness of the fractured layer, the multilayer sedimentary rock can be treated approximately as a system with infinitely thick top and bottom layers at fracture saturation.That should be useful in the design of engineering systems and in the prediction of fracture spacing in hydrocarbon reservoirs and groundwater aquifers.