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Gibson, S. G.

Publications and source records attributed to Gibson, S. G..

The computation of mesh configurations for three-dimensional flow analysis

A geometry modeling method was developed to define three-dimensional mesh configurations, which were expressed by the set of surface intersections with a coordinate mesh. These configurations define bodies for transonic potential-flow computation in simple physical coordinates. Various configurations were prepared for 3-D potential flow analysis, including many bare inlet models in cylindrical coordinates. Trimmed surface models were used to prepare nacelle installation configurations. A variety of ducts and mixers were represented. Analytically defined mesh/surface intersections were compared with similar data obtained from the corresponding surface model. Parameters for an analytic surface definition from mesh-surface intersections obtained from a model of the surface were produced. In both studies the modeling accuracy was shown to be compatible with the flow analysis requirements. This technique fulfills the requirements of the associated three-dimensional potential-flow analysis. It preserves the flow analysis method's superior flexibility for adapting to unusual geometries. The geometry modeling technique is supported by a sufficient set of tools for effective use by general users, and sufficient accuracy was demonstrated.

Gibson, S. G.↗

User's manual for master: Modeling of aerodynamic surfaces by 3-dimensional explicit representation

A system of computer programs was developed to model general three dimensional surfaces. Surfaces are modeled as sets of parametric bicubic patches. There are also capabilities to transform coordinates, to compute mesh/surface intersection normals, and to format input data for a transonic potential flow analysis. A graphical display of surface models and intersection normals is available. There are additional capabilities to regulate point spacing on input curves and to compute surface/surface intersection curves. Input and output data formats are described; detailed suggestions are given for user input. Instructions for execution are given, and examples are shown.

Gibson, S. G.↗