Abstract: In this paper, the Poincaré and Poincaré-Cartan integral invariants in nonconservative systems are established. According to the integral invariant, he non-linear oscillation of particles in 3-folded symmetry spiral sector cyclotron is investigated, It turns out that the method is successful.

Key words: T-bifurcation, steady blood flow, unsteady blood flow, macromolecular transport, pulsatile blood flow