posted on 2021-05-22, 12:29authored byScott A Warwick
Dynamical behaviors of a system consisting of a Saito-450 3-cylinder, 4-stroke engine and a variable pitch propeller are studied. The kinemtical equations for the planar 8-bar internal combustion engine are established using a complex number method. The nonlinear dynamical equation for the engine-propeller system is obtained using the Lagrange equation and solved numerically using a computer code written in the Matlab language. Various simulations were performed to study the transient and steady state dynamical behaviors of the sophisticated multiple rigid body system while taking into account the engine pressure pulsations and aerodynamic load. The steady-state motions of the propeller shaft for different engine powers and speeds were obtained and decomposed using the Fast Fourier Technique (FFT). Results presented in this thesis provide necessary input for studies of flexible body dynamics where the torsional vibration of the propeller shaft is of practical interest to design engineers in the aerospace industry.