A method for calculating in viscid supercritical flowfields about axisym metric inlet cowls with centerbodies is presented. A finite-differe nce approximation to the full-potential equation is solved under a general coordinate transformation, using a numerical evaluation of the transformation matrix at each mesh point. For the present problem, a boundary conforming coordinate system was generated by a sequence of conformal and shearing transformations, but this transformation is not essential to the method. Both the quasiconservative and non- conservative forms of Jameson's rotated differencing scheme are used, and the difference equations are solved by relaxation. Numerical results for pressure distributions generally agree well with experiment. INCE the initial success of Murman and ColeJ in applying the type-dependent differencing concept to the transonic small-disturbance equation, this technique has been ex- tensively applied to compute transonic flowfields about airfoils, using both the small-disturbance and full-potential equations. For flowfields around blunt bodies, the full- potential equation is required to properly resolve the solution in the vicinity of the stagnation points. The introduction of the rotated differencing scheme by Jameson 2 enables the use of line relaxation for solving the full-potential equation. There have been many successful applications of the rotated difference scheme to compute inviscid transonic flowfields around blunt-nosed bodies, including nacelle inlets and wing- body configurations. For a flowfield around a nacelle inlet, Arlinger3 applied a conformal mapping technique to trans- form the full-potential equation to a boundary conforming coordinate system. Caughey and Jameson4 solved the same problem using a sequence of simpler transformations, and studied ways to accelerate the iteration scheme used to solve the difference equations. Reyhner5'6 solved the full-potential equation in a Cartesian mesh. This requires an interpolation scheme to accurately treat the surface boundary condition. The mapping techniques generally require transforming the governing equations under the sequence of mappings. For complex geometries, these transformations can become a lengthy and tedious process. The boundary interpolation scheme has the advantage of always differencing the equation in Cartesian coordinates. There are, however, various types of irregular boundary elements, and the effort required to keep track of surface-mesh intersections is a major drawback in the application of this scheme. Caughey and Jameson7 proposed a finite-difference scheme to compute the supercritical flowfield about wing-body configuration using a form of the
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