O efeito giroscópico altera as freqüências naturais dos rotores, fazendo aparecer um par de freqüências denominadas como freqüências de "whirling", sendo uma maior com rodopio no mesmo sentido da rotação e outra menor em sentido contrário. A ocorrência de uma ou de outra depende da rotação e das condições iniciais do problema. Quando a velocidade de rotação atinge um múltiplo inteiro destas freqüências de "whirling" ocorre uma vibração violenta que pode destruir a máquina. No projeto de máquinas rotativas deve-se evitar que o sistema permaneça nestes pontos

The gyroscopic effect changes the natural frequencies of rotaiy machines, which induces the appearence frequencies called whirling frequencies. The whirling frequency direction of the rotor and value higher than natural frequency presents a rotation in the other, the (lower) rotate in the other direction. The occurrence of the higher or lower the initial condition of the problem. When the same frequency depends on the rotation and on velocity of rotation reach a whole entire multiple of the value of the whirling frequency, there is a violent vibration which may damage the machine. In the design of rotary machine operations, in the proximity to these points must be avoided. In this work, a Computer software to determine the whirling frequency using fmite elements technique, and considering the effects of the rotary inertia and shaft bending shear, has been developed. has considered three basic elements: shaft, disc and bearings. The discretization process The damping, stiffness mass and gyroscopic matrices has been assembled by this modelmg. The order of these matrices depends on the number of nodes and for every node, there are degrees of freedom The problem has been described in the State space, m order to four obtain the classic eigenvalue and eigenvector problem.