VNAP: a computer program for computation of two-dimensional, time-dependent compressible, viscous, internal flow

Technical Report · Wed Nov 01 04:00:00 EST 1978

DOI:https://doi.org/10.2172/6780521· OSTI ID:6780521

Cline, M C

A computer program, VNAP, for calculating viscous, as well as inviscid, steady and unsteady, internal flow is presented. The Navier--Stokes equations for two-dimensional, time-dependent, compressible flow are solved using the second-order accurate, MacCormack finite-difference scheme. The boundary mesh points, except no-slip wall points, are calculated using a characteristic scheme with the viscous terms treated as source functions. The no-slip wall points are computed using the MacCormack scheme with the derivatives normal to the wall approximated by one-sided differences. An explicit artificial viscosity is included for shock calculations, and a mixing-length model is included for turbulent flows. The fluid is assumed to be a perfect gas. The steady-state solution is obtained as the asymptotic solution for large time. The flow boundaries may be arbitrary curved solid walls or free jet envelopes. Typical problems that can be solved are flow in pipes and ducts; converging, converging-diverging, and plug nozzles; subsonic and supersonic inlets; and free jet expansions. The accuracy and efficiency of the program are shown by calculations of several inviscid, viscous, and turbulent flows. The program and its use are described completely, and five sample cases and a code listing are included.

• Research Organization: Los Alamos Scientific Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6780521
• Report Number(s): LA-7326
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
COMPRESSIBLE FLOW
COMPUTER CALCULATIONS
COMPUTER CODES
DIFFERENTIAL EQUATIONS
EQUATIONS
FINITE DIFFERENCE METHOD
FLUID FLOW
GAS FLOW
ITERATIVE METHODS
NAVIER-STOKES EQUATION
NUMERICAL SOLUTION
TURBULENT FLOW
V CODES
VISCOUS FLOW