A Windows Program for Airfoil Design Using B-Splines
M.S. Thesis
Matthew MacLean

The objective of this thesis has been threefold. First, the formulation of splines has been studied and their development into a computer algorithm has been implemented. Splines represent a powerful concept in computer modeling and geometric representation, for, as parametric curves, they provide a compact way to store the information defining a curve or surface.  B-splines have been exclusively used in this thesis, although other types of splines exist.
The second goal of this thesis was to learn and utilize C++ as a programming tool in the demonstration of B-spline techniques. C++ was chosen because it is object-oriented, and because it is the chosen language of the Microsoft Windows PC platform.  Many languages are object-oriented, but C++ was chosen to make use of its libraries to build standard Windows interfaces and objects.
The third piece of this thesis is an effort to explore the fundamentals of inter-language communications. Many old scientific codes are already written in older languages like FORTRAN, so it is advantageous to re-use those codes where possible.  Digital Visual FORTRAN, a module of the Microsoft Visual Studio, has provided a powerful tool in their integration of multiple programming languages for Windows applications.  Using Visual Studio, it is possible to re-use existing FORTRAN code and envelop it in a C interface using a dynamic link library (DLL) file.
This thesis uses a C++ application for defining any typical airfoil using B-splines.  The software package calls XFOIL, a code written in FORTRAN to evaluate the aerodynamic characteristics of those airfoils. Further, those characteristics have been compared to those of the original geometry to evaluate the interpolation process used by the splines.

--> Download Complete Document: PDF File <--