Abstract
An analysis of the friction losses in a centrifugal compressor stage is used to suggest a new form of correction equation for the effect of Reynolds number on efficiency. This equation relates the effect of Reynolds number to the surface roughness, the impeller outlet width ratio and the work input coefficient. Systematic tests on a wide range of compressor stages are used to calibrate the single empirical coefficient in the equation. Despite its simplicity this equation provides more accurate predictions of the Reynolds number effects than existing empirical methods.