A gas turbine engine and a diffuser therefor

摘要

A gas turbine engine with first and second axial flow compressors and an intercooler therebetween is provided with a bend diffuser (16) and a radial flow diffuser (18) to diffuse the air leaving the downstream end (38) of the first axial flow compressor (14) at a first radial distance (R1) from the axis to the upstream end of the intercooler at a second radial distance from the axis . The bend diffuser (16) comprises a first radially outer wall (54) and a second radially inner wall (56). The first wall (54) is elliptical and the second wall (56) has a profile derived from a relationship between the local area ratio and the path length around the arc such there is rapid diffusion in the bend diffuser (16) without fluid flow separation from the first wall (54). $$