Artificial Mass Concept and Transonic Viscous Flow Equation,
Abstract
By varying the grid clustering on the surface of an airfoil, it was observed that symmetric shocked solutions develop with a nonunique shock strength and location when numerically solving the full potential equation. It is shown analytically that the conventional form of artificial density (or viscosity) produces a number of truly nonlinear terms which are suspected to be the cause of the nonuniqueness for all the finite grid sizes. A concept of artificial mass flow is shown to be suitable for analytically evaluating a new exact form of the switching function that eliminates all the nonlinear terms for any value of the local Mach number. The resulting expanded full potential equation then becomes a third order partial differential equation of permanently parabolic type resembling Sichel's transonic viscous flow equation. Consequently, our expanded full potential equation does not require the introduction of the customarily-used artificial time concept. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1984
- Accession Number
- ADP002946
Entities
People
- G. S. Dulikravich
- P. Niederdrenk
Organizations
- University of Texas at Austin