Abstract: The radial distribution of circumferential velocity in hydrocyclone is simulated by computer discrete calculation and the stability of its fluid is judged according to Rayleigh discriminant. It is found that the fluid flow in hydrocyclone is unstable, which is unfavorable to the separation process in hydrocyclone. It is pointed out that it will be a new way for hydrocyclone development to reduce the instability of the fluid so as to improve the performance of hydrocyclone.

Key words: Hydrocyclone, Fluid, Circumferential speed, Stability