The purpose of this project is to investigate the influence of different mistuned blades arrangements on free-vibration response and dynamics of bladed disk. This rotor belongs to the first stage of the Low Pressure Compressor (LPC) in the NK-36ST engine, used as Gas Turbine Unit. Firstly, will be analyzed the influence of different mistuned patterns on mode shapes and natural frequencies. Then, a finite elements model of the LPC will be created and a CFD simulation run in order to evaluate the exciting aerodynamic force acting on each blade. The estimated force, written in harmonic form in function of Engine Order and time, will be used to excite blades in a transient structural analysis so as to minimize stress scatter and find the best mistuned arrangement..