Offset ribs for heat transfer surface

Claim 1

Means for preferentially augmenting the local heat transfer coefficient of two heat transfer surfaces defining an internal, spanwisely extending cooling channel in an airfoil body having an external suction side and an external pressure side and a flow of gas therethrough, comprising a plurality of ridges disposed on the first surface and the second surface and spaced streamwisely with respect to the gas flow, each ridge including a first end portion extending generally laterally with respect to the gas flow, a second end portion parallel to the first portion, the second end portion further being offset with respect to the first portion, and an intermediate portion, extending between the proximate ends of the first and second end portions, and oriented substantially perpendicular thereto, and wherein the upstream end of the first portions of the first surface plurality of ridges are located adjacent a first region of the suction side subject to elevated thermal loading, and wherein, the upstream ends of the first portions of the second surface plurality of ridges are located adjacent a first region of the pressure side subject to elevated thermal loading, and wherein the intermediate segments of the first surface ridges are located concordally with a second region of the suction side subject to elevated thermal loading, and wherein the intermediate segments of the second surface ridges are located concordally with a second region of the pressure side subject to elevated thermal loading.