This paper describes the incorporation of simple potential flow theory with limited interactive graphics to produce a computer program for the potential flow analysis of a wide variety of two-dimensional bodies. The genera/program approach is explained and three particularly effective program techniques developed specifically for use in this program are described. These techniques allow the location of stagnation points, the closure of a streamline, and the tracing of streamline patterns for complex flow. Several possible applications of the program are cited and some exampies of these applications are shown.
This paper describes the incorporation of the principle of superposition and limited graphics capabilities to produce a fast and relatively versatile computer program for the analysis of two-dimensional bodies in potential flow. Purely digital applications of the superposition technique 1'2 entail the solution of a large system of linear equations, and thus can be very time-consuming and have large core storage requirements. The objective of this work is to explo(t the advantages of man-machine interaction by implementing a faster method which requires less core storage and by having a graphical display device present results of the analysis. Using this approach the time requirements of hand or mechanical plotting of streamline patterns and pressure distributions can be reduced considerably, and the computer can be made to graphically communicate. Several studies of external flow behaviour 3-6 have capitalized on the rapid, graphical display characteristics of interactive graphics to enhance man-machine interaction.
The general program approach is described in the next section. In order to implement this approach and to satisfy the objective stated above, it was necessary to develop three program techniques for: locating stagnation points; producing a closed streamline (representing a body contour); and tracing streamlines. These are detailed in the third section. A brief description of the computer system used during the development and use of the program is then presented along with an example of its operation. The following section details results and applications of the program, and the final section summarizes the article.