Abstract:

VFP is a CFD (computational fluid dynamics) method coded in FORTRAN for calculating the flow field and aerodynamic forces of an isolated wing (denoted usually as a wing-alone) or a wing-body combination (denoted usually as a wing-body) in a subsonic freestream, including the effects of shock waves and boundary layers. VFP uses a relaxation process to solve finite-difference forms of the full nonlinear velocity-potential equation for the flow around the three-dimensional geometry. The viscous effects are modelled using a coupled semi-inverse swept tapered integral boundary-layer method. The VFP program was developed over a period of years at ARA, Bedford and RAE/DERA (now QinetiQ), Farnborough, and is made available by ESDU under the terms of an agreement with QinetiQ. Used originally on mainframe computers, VFP has provided valuable data in the design of a number of aircraft. With advances in computers, it has become possible to perform runs of VFP on a PC within a few minutes. One of the advantages of the VFP method is to provide a rapid process to produce valuable data to assess the aerodynamic qualities of wings as part of the design process.

This Item, Part 2 in the Series dealing with VFP, is concerned primarily with the practical aspects of running VFP and its associated programs in order to obtain reliable results.

See also:

• ESDU 13013: Viscous full-potential (VFP) method for three-dimensional wings and wing-body combinations. Part 1: Validation of VFP results with experiment and comparisons with other methods.
• ESDU 13014: Viscous full-potential (VFP) method for three-dimensional wings and wing-body combinations. Part 3: VFP error messages, failures and suggested remedies.
• ESDU 21002: Viscous full-potential (VFP) method for three dimensional wings and wing-body combinations. Part 4: VFP analysis programs for flow breakdown and forces and loads.