Abstract:

ESDU Aero W.S.00.03.05 presents curves for obtaining by the shock-expansion method the distribution of pressure coefficient around an aerofoil in supersonic flow with an attached nose shock wave. The curves are derived from data on the flow through shock waves and simple-wave flow but are restricted to small deflections and so provide a better accuracy than can be obtained using the curves of ESDU Aero S.00.03.08 to 10. The conditions for shock wave attachment are given in ESDU Aero S.00.03.16. One graph gives the pressure coefficient plotted against upstream Mach number for various values of an abrupt flow deflection angle; values of positive deflection relate to compressive deflections and negative to expansive deflections. Superimposed are curves of downstream Mach number. The other graph gives curves of pressure ratio through an expansive deflection plotted against upstream Mach number for various values of deflection angle; again curves of downstream Mach number are superimposed. The method assumes the effect of reflection of the expansion waves from the shock waves is negligible, which, for the range of Mach numbers covered (up to 4 upstream) is reasonable. A worked example shows how the curves are used to determine the pressure distribution on a double-wedge section at incidence.