Datum determination in a turbulent flow aircraft simulation

摘要

A datum line 16, 18, such as the leading or trailing edge of an aerofoil component 10, is identified on a surface mesh 12, 14 of the component 10 for use in a simulation. The method comprises the steps of: a) defining a reference coordinate system including a direction X, which may be a general flow direction over the component; b) defining a span variable that varies along the component in a forwards marching direction 8, for example corresponding to the root to tip direction of the aerofoil; c) selecting a first frontal node n 1 on the datum line; d) using a Pareto front algorithm to define the datum line 16, 18 at an extremity of the surface mesh with respect to the X direction, the Pareto front algorithm evaluating a criterion for dominated nodes and operating on a Pareto variable to select successive connected frontal nodes that form the datum line 16, 18, wherein the Pareto variable is the X coordinate and the criterion for dominated nodes is a span value less than that of the selected frontal node n 1 .