Rafał Bartłomowicz

1. Introduction The blade number is known to be a crucial design parameter of every annular cascade presented in a modern aircraft jet engine. Its aerodynamic significance lies in the definition of solidity and, therefore, the balance between the effective flow deflection, blade loading, friction losses, and area contraction effects [1]. Its main structural role is to ensure resonance-free rotor–stator interactions inside the nominal range of engine rotational speeds [2,3,4,5,6].