LOCALLY INTERACTIVE LAMINAR SEPARATION BUBBLE MODEL

A semi-empirical laminar separation bubble model has been developed an d incorporated into an airfoil design and analysis program. The genera lity and efficiency of this model have been achieved by approximating the local viscous/inviscid interaction, the transition location, and t he turbulent reattachment process within the framework of an integral boundary-layer method. In particular, the whole bubble flowfield is fo und to depend on two empirically derived dimensionless parameters and on the transition location as calculated using linear stability theory . Comparisons of the predicted aerodynamic and boundary-layer characte ristics with experimental measurements for several airfoils show excel lent and consistent agreement for Reynolds numbers from 2 x 10(6) down to 1 x 10(5).