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Rizzi, A.

Publications and source records attributed to Rizzi, A..

High resolution solutions of the Euler equations for vortex flows

Solutions of the Euler equations are presented for M = 1.5 flow past a 70-degree-swept delta wing. At an angle of attack of 10 degrees, strong leading-edge vortices are produced. Two computational approaches are taken, based upon fully three-dimensional and conical flow theory. Both methods utilize a finite-volume discretization solved by a pseudounsteady multistage scheme. Results from the two approaches are in good agreement. Computations have been done on a 16-million-word CYBER 205 using 196 x 56 x 96 and 128 x 128 cells for the two methods. A sizable data base is generated, and some of the practical aspects of manipulating it are mentioned. The results reveal many interesting physical features of the compressible vortical flow field and also suggest new areas needing research.

Murman, E. M.↗

Transonic solutions of the Euler equations by the finite volume method

An investigation is conducted of the time-accurate convergence of representative transonic flows to a steady state under given constraints of time-accuracy. Factored explicit and implicit difference operators are used to accelerate the calculations. Attention is given to flow at a Mach number of 1.35 past a circular cylinder and supersonic flow past a NACA 0012 airfoil for three different Mach numbers. Questions of transonic wave behavior are considered along with the equations of motion and the characteristics of the mesh network.

Rizzi, A.↗

Finite-volume solution of the Euler equations for steady three-dimensional transonic flow

A numerical finite-volume method is proposed for solving the Euler equations of a steady three-dimensional flow. The subsonic regions embedded in steady supersonic flow about aircraft are computed by introducing a time-dependent coordinate system that maps the fuselage and wing into one coordinate surface. The suitability of the method to a delta-winged aircraft is demonstrated, and its applicability to rectangular-winged aircraft and problems in internal transonic flow is pointed out.

Rizzi, A.↗