The implementation of influence boundary procedures in CFD

The current paper presents and categorizes influence boundary methods. These are computational fluid dynamics procedures that are based on reducing the scope and resource requirement of a computational fluid dynamics problem while minimizing the error in the approximated domain by a systematic application of the effect of the full or surrounding domain on the reduced one. The objective is to present a useful tool for computationallyintensive CFD applications. Equations and automatic procedures for determining the reduced domain are presented. The procedure is validated using flow over a cylinder, airfoil, and the B747-200 aircraft. The error in the procedure is determined for an airfoil/flap and wing/store configuration. The results show that the automatically-determined influence domain procedure, aside from obviating the need for ad-hoc determination of the size and shape of the influence domain, it also minimizes the error in the influence boundary calculation. In addition, it is demonstrated that calculations with errors below 20% at Ma = 0.25 and 10% at Ma = 0.8 can be performed at about 30% of the computational cost of a full domain calculation.