Numerical solution of unsteady, compressible, Reduced Navier-Stokes equations

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5607532

Ramakrishnan, S V

The motivation for this dissertation came from a desire to explore the limits of applicability of the Reduced Navier-Stokes (RNS) equations. Some steady flows with larger separation and unsteady flows with vortex shedding are investigated with unsteady, compressible RNS equations. The line-relaxation procedure previously developed to solve the steady RNS equations is extended to solve the unsteady equations. It is ensured that the extended algorithm is time-consistent. The Sherman-Morrison technique is used to increase the stability of the line-relaxation procedure. A modification of the standard line-relaxation procedure that is more stable and efficient is presented. The five-point coupled strongly implicit procedure (CSIP), employed in the study of the stream function-vorticity form of the full NS equations, is modified to solve a nine-point finite-difference scheme. The use of a CSIP algorithm enhances the utility of the RNS procedure by extending its applicability to a general grid specification. The usefulness of the RNS approximation in the study of steady flows with large separation and unsteady flows with vortex shedding is demonstrated by comparing some RNS solutions with available full Navier-Stokes calculations.

• Research Organization: Cincinnati Univ., OH (USA)
• OSTI ID: 5607532
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
ALGORITHMS
DIFFERENTIAL EQUATIONS
EFFICIENCY
EQUATIONS
FINITE DIFFERENCE METHOD
FLUID FLOW
ITERATIVE METHODS
MATHEMATICAL LOGIC
NAVIER-STOKES EQUATIONS
NUMERICAL SOLUTION
PARTIAL DIFFERENTIAL EQUATIONS
STABILITY
STEADY FLOW
UNSTEADY FLOW
VORTICES