Papers by Keyword: Parameterization

Abstract: This paper considers the diaphragm spring of a mechanical clutch being composed by a conical disk spring and trapezoidal lamellar springs attached to the disk spring. After analytical calculation of the disk spring a numerical structural analysis was performed in order to validate the 3D model of the disk spring. A design optimization with 4 design variables was done for the disk spring and, based on the optimized design, the 3D model of the diaphragm spring was built. A 6 design variables model of the diaphragm spring was proposed for design optimization analysis having as design objective the minimization of the maximum equivalent stress during disengaging the clutch.

Abstract: In this paper it is presented the design optimization of the rear wing of a sports car. The wing profile was parameterized with three variables, the angle of attack was the fourth variable and the objective function was to minimize the lift over drag ratio. Three virtual models were considered: a model without rear wing, a model with a rear wing with initial profile and position and a model with optimized rear wing. For these three models the drag and lift coefficients were calculated for comparison along with drag and lift forces.

Abstract: In this paper it is presented the design optimization of the diaphragm spring for a mechanical clutch. The slot shape of the fingers was parameterized and the objective function was the maximum tangential stress to be minimized subjected to the constraint that the deflection of the spring on exterior diameter in the spring centreline direction has a minimum certain value when the clutch is disengaged.

Abstract: A novel and simple parameterization method using an ensemble of unconditional model realizations is applied to decrease the dimension of the misfit objective function in large-scale history matching problems. The major advantage of this parameterization method is that the singular value decomposition (SVD) calculation is completely avoided, which saves time and cost for huge matrix decomposition and the eigenvectors computations in parameterization process. After objective function transforms from a higher dimension to a lower dimension by parameterization, a Monte Carlo approach is introduced to evaluate the gradient information in the lower domain. Unlike the adjoint-gradient algorithms, the gradient in our method is estimated by Monte Carlo stochastic method, which can be easily coupled with different numerical simulator and avoid complicated adjoint code. When the estimated gradient information is obtained, any gradient-based algorithm can be implemented for optimizing the objective function. The Monte Carlo algorithm combined with the parameterization method is applied to Brugge reservoir field. The result shows that our present method gives a good estimation of reservoir properties and decreases the geological uncertainty without SVD but with a lower final objective function value, which provides a more efficient and useful way for history matching in large scale field.

Abstract: Methods about parametric reverse modeling have been studied based on products’ point clouds by comparing model rebuilding processes in different ways, such as collaborative reconstruction based on both reverse engineering software Geomagic and 3D modeling software, reverse and forward hybrid modeling based on Rapidform. It‘s concluded that reverse and forward hybrid modeling based on Rapidform takes more advantages in parametric reverse modeling, It is more rapid , accurate, and closer to the design intent.

Abstract: Based on the functional expression methods of wind turbine airfoils, the method of the correction to parameter factors of shape function by iterative calculation in the principle of making the residual error minimum between the fitting airfoil and the target airfoil is presented in this paper, which makes the fitting precision improved compared with the parametric representation of original airfoils. The method of the correction to parameter factors of shape function proposed in this paper is used for parametric representation of more than 20 kinds of typical airfoils and then the geometric and aerodynamic convergence are intensive studied. The results show that the minimal order of the integrated expression of airfoils is decreased by the proposed method in this paper and the mathematical models of airfoils which facilitate the unification of optimal design are established.

Abstract: This paper presents a design methodology of laminating tools for automotive interior parts using CATIA software package. The authors developed a software tool named LTFrameDesign using VBA for Application under CATIA package, which automatically generates the main frame of the laminating tool according to the parts shapes, its dimensions and designer requirements. The software automates some stages of standard design and minimizes the design time and costs. The paper also presents the design stages which are followed by the user to obtain a 3D complete assembly of the laminating tool.

Abstract: All students in mechanical engineering courses receive training in using at least one parametric and associative 3D modeler. From the point of view of the logic behind the geometric design, a very important issue is how to parameterize the model, or put in other words, how to achieve the right balance between dimensions, as independent parameters, formulas (linking dimensions) and geometric constraints (parallel, concentric, horizontal etc.). We arrive following this logic to the notion of degrees of freedom of the model, as expressing the number of dimensions still free for a dynamic edit. The papers aim is to provide a case study capable to assist students in understanding how a good model could be built. The case study will be integrated in an on-line course, offered by our university as an expression of its commitment in developing e-learning applications [.The paper proposes a slightly different approach, compared with the ones presented in [2, 3, . While in the mentioned sources a graph approach is considered, our paper proposes a matrix oriented analysis, coupled with a live analysis of the model behavior. The paper also proposes different other models as good examples to be used in the teaching process.

Abstract: Globoidal indexing cam mechanism is the spatial indexing mechanism of high speed, high precision and widely used in modern machine and automatic production line.But the working profile of the globoidal indexing cam mechanism is not fair for the space curved surface and it is difficult to model. The traditional design method requires a great deal of calculation, and the design process is complexed, we have to repeat the entire design process when changing any parameters, lead to low design efficiency and poor universality. To solve above disadvantages, this paper used the space meshing principle and space coordinate transformation method, based on 3 d modeling software Pro/ENGINEER, using vc + + and Pro/toolkit for secondary development, realize the parametric modelling of globoidal indexing cam mechanism, and the simulation and analysis of the generated cam mechanism.

Abstract: Downhole motor is an instrument to drill oil wells, different from rotary drilling in working methods. While downhole motor works, the drilling stem of which remains still supplies power to bits directly so that a much higher transmission efficiency of power can be achieved. Downhole motor has been a key developing downhole tool recently. It is installed in a limited space with a certain diameter, asking for a higher power, so the design of which is rather difficult. This paper mainly studies the key components of downhole motor in structure design and its working characteristics. And parametric design employed in series design to shorten design cycle is presented in this paper. After taken Solidworks as a basic software platform and turbodrill turbine section with diameter of 245mm as an original model, parametric design of key components in downhole motor has been achieved by setting the parameters of key components, adding relations, editing program, creating a new part etc. Parametric design methods presented in this paper has already been applied in series design of downhole motor at Yangtze University.