Application of the Thin-Wing-Expansion Method to the Compressible Flow past an Elliptic Cylinder, with Special Reference to its Fourth Approximation

抄録

Both the complete and transonic thin-wing-expansion methods are utilized to obtain the steady irrotational flow of a compressible fluid past an elliptic cylinder. The velocity distribution over the surface is calculated up to the fourth powers in thickness ratio t. Then it is found that the fourth order perturbations include not only terms of O(t⁴) but also those of O(t⁴logt), and that the latter group becomes negatively predominant over the former in the transonic range. In calculating the fluid velocity near the stagnation point there still remains insurmountable difficulty even for moderate subsonic flow. The resulting expressions for an elliptic cylinder prove to be transformed into those for an parabolic cylinder.