초록 ▼

A prop-fan of the type having a high solidity factor (1 or greater) near the root fairing to a lower solidity factor (less than 1) near the tip and operable over a critical Mach No. range is designed for sound suppression by contouring the tip so that its sweep and sweep distribution of the leading

A prop-fan of the type having a high solidity factor (1 or greater) near the root fairing to a lower solidity factor (less than 1) near the tip and operable over a critical Mach No. range is designed for sound suppression by contouring the tip so that its sweep and sweep distribution of the leading and trailing edge bears a judicious relationship with the Mach surface. This feature is obtainable by designing the planform from a prescribed linearized or non-linearized acoustic theory and tailoring in the sweep so that the leading and trailing edges fall behind the Mach surface.

대표청구항 ▼

A prop-fan having a plurality of rotatable blades supported in a hub for pitch change movement, the airfoil section having a solidity factor of 1 or greater adjacent the root and less than 1 adjacent the tip and operable at a speed where the Mach No. is critical or above critical and the tip speed i

A prop-fan having a plurality of rotatable blades supported in a hub for pitch change movement, the airfoil section having a solidity factor of 1 or greater adjacent the root and less than 1 adjacent the tip and operable at a speed where the Mach No. is critical or above critical and the tip speed is transonic or supersonic, said blade having a preascertained sweep distribution which for a given Mach surface for both the trailing and leading edge at a given operating condition said trailing edge is behind the trailing Mach surface and said leading edge is behind said leading Mach surface.