On the solution of laminar flow over a circular cylinder started impulsively from rest

A numerical method for calculating the unsteady laminar flow over a circular cylinder started impulsively from rest is presented. The governing boundary layer equations were solved using Keller's two-point finite-difference method (standard Box method). In regions where the streamwise velocity develops backflow, the solution method was modified (modified Box method) by two different procedures which allow the calculation of such flows. Local skin-friction coefficients and displacement thickness values were computed for values of t up to 1.25. These quantities agree well with the predictions of Belcher et al., but do not agree with those of Telionis and Tsahalis.