Advanced Materials Research Vols. 301-303

Abstract: The AE signals of fiber reinforced composites in the tensile testing were processed by Hilbert-Huang transform. The AE signals were well recognized from the Hilbert-Huang spectrum. The experimental results show that the frequency range of matrix crack AE signals is below 200 kHz and the main frequency is nearly in 175 kHz. The frequency range of fiber breakage is above 200 kHz and the main frequency is nearly 250 kHz. While the frequency of delaminations is distributed all over the frequency range and the energy is distributed below 200 kHz. The experimental results also indicted that the intrinsic mode function (IMF) components of the AE signals processed by empirical mode decomposition (EMD) can reconstruct the original signals well, and the Hilbert spectrum of the IMF components can reveal the frequency and energy trends of AE signals.

Abstract: The approach to total weight reduction has been a key issue for car manufacturers as they cope with more and more stringent requirements for fuel economy. In sheet metal forming, local increases in product-sheet thickness effectively contribute to reducing the total product weight. Products could be designed more efficiently if a designer could predict and control the thickness distribution of formed products. This paper describes a numerical simulation and evaluation of the material flow in local thickness increments of products formed by an ironing process. In order to clarify the mechanism of the local increase in sheet thickness, a 3-D numerical simulation of deep drawing and ironing was performed using finite-element simulation. The effects of various types of finite elements that primarily affect thickness changes in original materials and thickness prediction were investigated. It was found that the sheet-thickness distribution could be predicted if the original material was relatively thick and if an appropriate type of finite element is selected.

Abstract: The research on the relationship between vortex evolution and diffusion of aerosol in human upper respiratory tract can deepen understanding of the characteristics of the particle deposition pattern in human upper respiratory tract and plays a very important role in analyzing the transition of aerosol in human upper respiratory tract. Large eddy simulation and an efficient Lagrangian particle tracking module were used to simulate relationship between vortex evolution and diffusion of aerosol in mouth-throat model in the conditions of the low intensive respiratory, and the vortex evolution and the mechanism of aerosol transition in human mouth-throat model were discussed. The results show that the diffusion of small aerosol particles follow the vortex structure very closely; the capabilities of the vortex for carrying aerosol particle increase with increase in vorticity, which can affect the diffuseness and deposition of the particles.

Abstract: Anti-corrosion coating in desulphurization flue of one wet flue gas desulfurization equipment (FGD) (model 1 and model 2) was designed and studied according to environmental and technical parameters of a coal-fired power plant. And relevant design requirements were confirmed. Application results showed that polyureas has wear and high temperature physical properties, so that it can be used in flue desulfurization equipment for anticorrosion. When the construction of a thickness of 2.0 mm, the high-temperature polyureas protective coating appearance smooth, EDM(electric discharge machining) 100% pass rate, adhesion 10.8 MPa, at 160 °C environment still had outstanding performance, that make sure it could reach its design life of the flue based on estimating the corrosion margin.

Abstract: This paper introduces the basic content of JRB320240B, including LCD tube foot function and operation sequence. Gives a kind of simple and practical hardware interface circuit of LCD and MCU. Design two general functions ,the painting line and circle; and indicate the algorithm of the bottom function. Then realize dials clock based on bottom function.

Abstract: The black soil in Jilin Province, famous for providing significant amount of commodity grain to entire China, had already begun to regress to disappear on different degrees. To study the structure degradation of black soil in Jilin Province, We used SPSS and matlab programming on data information processing, thirty indexes were chosen, factor analysis on twenty-three samples from different sites and depths in Jilin Province was carried out, and dynamic clustering analysis taking the score of main factor as the variable was performed in turn. Combining them together, as a result, then the degradation mechanism was evaluated and classified. The results showed that eight factors from thirty indexes were found as the principal factors by factor analysis. By dynamic clustering analysis, the areas where twenty-three samples came from could be classified into three types: high degradation, medium degradation and light degradation. Finally, the differences among index scores were analyzed respectively, and reasonable suggested measures to prevent the black soil degradation were stated.

Abstract: Explosion suppression by water mist is a new technology for the control of coal mine gas explosion with the three elements in the gas explosion at the same time. By building the physical model of the horizontal laneway in mine, and using the method of theoretical research and numerical simulation, this paper studies the relationship between the number of nozzles and H₂O percentage and the distance for stable percentage of H₂O, and provides a reliable for the design of water mist system for gas explosion suppression in the horizontal laneway in mine.

Abstract: According to microcosmic porous and throats model’s experiment which will be performed in Kexia layer, Qizhong district of conglomerate reservoir in Xinjiang oil fields, microscopic displacement mechanism of surfactant/polymer flooding was researched. Surfactant/polymer flooding has a significant effect on enhancing oil recovery because of the effect from the polymer’s viscosity and the surfactant’s interfacial tension. According to microcosmic porous and throats model’s experiment, the best polymer viscosity and surfactant interfacial tension were determined.

Abstract: The tomography of the gravel was obtained by the CT scanning technology to reconstruct the DEM models. Simultaneously, dimensional coordinates on the gravel’s surface were obtained. Then the surface of gravel was contracted and the coordinates of the shrunken shell were collected by the matlab ^[1] program. Based on these coordinates, two parameters which are radius threshold and overlapping factor were introduced to simulate the model. Then programs to reconstruct the DEM model were compiled. Spheres were used to rebuild the model and generate the irregular particle model automatically. The results indicated that the model was unique and the modeling process could be repeated. Simultaneously, the relationship between two parameters and the accuracy of the modeling were studied.

Abstract: Friction and wear performance is very complex. There are many tests methods and tests apparatus. In this paper, some basic of friction contact types and relative motion modes were introduced. Then some important friction tests methods and apparatus for composites were reviewed concisely. At last, a new friction method and equipment used in Kevlar/epoxy composite were proposed.