Papers by Keyword: Profile

Abstract: As a prevalent phenomenon, there are many streambed forms in rivers. The distribution of them was obviously in certain orders. This paper carried out numerical analysis and field work in natural rivers, to study the law of streambed forms' distribution. The results indicated that: A streambed profile can be considered as an overlay of two parts: the average streambed line which reflect the total slope (called 'Trend part'); the wave line vibrating along this average streambed line which reflect the effect of bed forms (called 'Form part'). The two parts were then distinctively separated by the wavelet analysis. Then the distribution of bed forms can be calculated and analyzed more scientifically.

Abstract: The vertical profiles along the coast are indispensable to research in coastal dynamic and Marine-topography evolution, but there is no perfect method to make them in rapid and batched way. This paper presents a feasible process to make it, there, Golden software surfer11.0 generates grid files by its scripter program, and then the files are called in VBA of EXCEL2003 to plotting the profiles. The process runs effectively in the physical model for the nourishment project of beach in Beidaihe New Area, it also makes a promotion in the report writing and data analysis. The result shows that the method is practicable.

Abstract: A 3D elastic-plastic finite element method (FEM) model of cold strip rolling for 6-high continuous variable crown (CVC) rolling mill was developed. The rolling force distributions were obtained by the internal iteration processes. The calculated error has been significantly reduced by the developed model. the absolute error between the simulated results and the actual values is obtained to be less than 10μm, and relative error is less than 1%. The developed model is significant in investigating the profile control capability of the CVC cold rolling mill in terms of work roll bending, intermediate roll bending and intermediate roll shifting.

Abstract: This paper, aimed at Ganglu 1500 hot strip rolling project, developed advanced shape control system. Entry profile calculation strategy was developed. Natural output profile was defined. Profile distribution model based on the buckling limit was developed. Practical applications in domestic 1500 hot strip mill show that the setup calculation strategy achieved good effect and enhanced the profile and flatness precision

Abstract: The principle of gear engagement and the relevant knowledge of gear geometry were used to introduce the dual meshing points involute-circular arc tooth gear in detail. At the same time, use the derived equation of the contact line and the tooth profile equation to describe the gear meshing process. Derive to this gear formula of coincidence degree calculate, in order to improve the transmission theory of the gear. Combine the gear contact line equation, equation of the tooth profile and transmission analysis, studies the meshing performance and serve as a theoretical basis for the gear design and application.

Abstract: In order to solve the problem of installation and measuring errors in the profile evaluation of large parabolic antennas, this paper proposes a new method for evaluating the profile of large paraboloidal antennas based on genetic algorithm and least square method. This method can effectively realize the adaptive adjustment of the measured points and the theoretical contour in the process of evaluating profile, which can eliminate the position error between the measured points and the theoretical contour that influences on the results of the profile evaluation. The availability of this method has been proved by simulation.

Abstract: The aim of the paper is to study the effect of the surface shape and perforation of plastics on sound absorption. Samples with different asperity heights, depths and numbers of holes were prepared by means of CNC milling machine. Experimental measurements of frequency dependencies of the sound absorption coefficient were realized by the transfer function method using Kundt ́s impedance tube at normal incidence of acoustic wave on the investigated materials. The study was performed on two types of polyurethanes. Different factors, that have influence on sound absorption, are evaluated in the conclusion of this work. Both investigated materials are also compared in terms of their ability to absorb sound.

Abstract: Controlling cold strip profile is a difficult and significant problem has been found in industry during thin strip rolling. At present choosing the new type of strip rolling mill is the one of main methods to control the strip shape quality in cold rolling. The influences of rolling process parameters such as the work roll cross angle and work roll shifting on the strip shape and profile of thin strip are recognised throughout this study. The results show that the roll crossing and shifting is efficient way to control the strip shape. The increase of the work roll crossing angle would lead to improve the strip profile significantly by decreasing the exit strip crown and edge drop. The strip profile would be enhanced if the axial roll shifting was increased. Moreover, the total rolling force was analysed in detail by changing the roll cross angle and axial shifting roll.

Abstract: Helicoidal surfaces correspond to a cathegory of widely spread surfacesin the technical field. From the point of view of the manufacturing of helicoidal surfaces through the moving of a profile around the helix, the two elements defining such a surface can be distinguished: the profile and the helix. The numerical determination of the profile of the disc type tool drawn on an analytical method with a large number of points [1- (the number reaches even 1500 in some cases) implies a great effort so that the technician can verify the correctness of results, even in the present case when there is the possibility of the numerical determination through the resolution of the inverse problem of the frontal profile of the complex helicoidal surface. In order to facilitate this work and to give the possibility of introducing some new profiles in the projection system, some methods of grapho-analytical determination have been conceived to process the profiles of the complex helicoidal surfaces, as well as the profiles of the helicoidal surfaces for a given tool profile. This paper presents the graphic-analytical determination of the disc tool profile designed to dress the complex helicoidal surfaces. The methods referred to by using the possibilities provided by the programming environment AutoCAD and its development languages allow to determin numerically the profile of the disc-cutter with a high precision, above the precision level required in practice.

Abstract: Oily sludge is a mixture of oil and sludge, produced during the process of crude oil production and gathering, contains crude oil, heavy metal and organic toxic and harmful substances, and with the characteristics of high moisture content, poor liquidity and big volume. The recycling and disposal of it has been one of the most important aspects of enviromrntal protection in oil industry. In this paper the origin nature and hazards of oil sludge were described, the existing oily sludge treatment process from the aspects of quenched separation, heat treatment, extraction, biological treatment were introduced, and looks forward to the development of the oil sludge treatment technology.