Computer-Aided Geometry Modeling

Techniques in computer-aided geometry modeling and their application are addressed. Mathematical modeling, solid geometry models, management of geometric data, development of geometry standards, and interactive and graphic procedures are discussed. The applications include aeronautical and aerospace structures design, fluid flow modeling, and gas turbine design

Strategy development for object-oriented multiblock grid generation and adaptation to complex geometries

The first part of the thesis deals with the strategy development for multiblock structured grid generation to complex geometries. Based on the grid generation practices over years, a set of grid construction rules is developed to provide the CFD engineer an object-oriented method for grid design. The essential core of the object-oriented method is to decompose a complex meshing task into a set of sub-tasks, which are treated individually at a lower level of both geometry and topology. The grid construction rules cover the questions of dealing with selection of meshing direction, generation of surface description and block topology building. To explain this grid design method, an example, dealing with a highly complex geometry, is demonstrated. The second part of the thesis deals with the strategy development for multiblock structured grid adaptation. Since a grid can be adapted with or without a flow solution, the terminologies passive and active grid adaptation are introduced to describe a solution-dependent or a solution-independent grid adaptation. Passive grid adaptation is performed by generating adequate block topologies, such that a local enrichment of grid points can be achieved. It consists of three concepts: one-dimensional clustering of grid lines, block encapsulation, and smart block. The method for solution-dependent grid adaptation is developed based on the idea of grid optimization. A grid is adapted by minimization of objective functions, in which relations among weight functions and grid line distribution are formulated. The measures for grid quality, such as smoothness, cell aspect ratio, and orthogonality, are formulated as control terms of the objective functions to improve grid quality. In addition, a concept of smart cell used for solution-dependent grid adaptation is proposed in this thesis

Workshop on the Integration of Finite Element Modeling with Geometric Modeling

The workshop on the Integration of Finite Element Modeling with Geometric Modeling was held on 12 May 1987. It was held to discuss the geometric modeling requirements of the finite element modeling process and to better understand the technical aspects of the integration of these two areas. The 11 papers are presented except for one for which only the abstract is given

Aeronautical engineering: A special bibliography with indexes, supplement 82, April 1977

This bibliography lists 311 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1977

3D model reconstruction from vector perpendicular projections

This scientific monograph deals with the issue of 3D model reconstruction of a rotation part from its orthogonal projections recorded on a digitalized drawing in vector format and with computer-aided automation of the process. The topic is a partial task of the domain focused on generating the 3D part model or product from a technical drawing. The introduction comments on the analysis of the current state of information in the field. The rules of projecting the parts in a technical drawing are described as well as the related terminology and methods in computer graphics, mathematics and geometry. The computer-aided ways of modeling solids are analyzed. The introductory part is complemented by an overview of existing solutions by other authors and by the possibilities of my own method development. The monograph core is focused on the proposal of proceedings and algorithms for transformation process automation of 2D vector record comprising orthogonal projections representing the rotation part on a 3D model. The pilot implementations of algorithms and their verification by testing on the selected sample of geometric shapes are added