1. The results shown in figure 10 (M= .8, a=Oo) indicate that increasing the overlap region decreases the number o f iterations for convergence, however, this also increases the computing effort. To minimize the computing time the Carteslan grid also the inner boundary o f the Cartesian grid should not be located less than 0.25 chord length away from the airfoil. The use o f Improper interfacing arrangement produces inaccurate results and slows down convergence, i n some cases artificial shocks are generated. The peaky pressure distribution in figure 11 i s corrected by increasing the overlap region and changing the step size in bath subdomains. Should the shock extend into the overlap region, the interpolation process can produce errors i n the shock location and strength. Comparison o f the results o f the pre e t method with those obtained from the TAiR codes 5(figure 12) indicates that the maximum relative error in the mnicline position did not exceed 1.5%. should overlap 15 -25%of the curvilinear grid,
2. 0 en '8-6- 51fl 38 present method
3. cases considered, the ratio o f the step size in the curvilinear grid to that of the Cartesian grid is kept i n the range (1 - 3) in the overlap region This proved to give accurate and stable results.
4. Boppe, C. W., and Stern, M. A. "Simulated Transonic Flows for Aircraft with Nacelles, Pylons, and Winglets", AlAA Paper 80-0130.