The vortex signal is weak and easy to be submerged by high level noises when the vortex flow sensor measures low flowrate in a small caliber.It is difficult to pick out the useful vortex frequency.In order to solve this problem,a new method based on Duffing oscillator is proposed to detect the weak vortex signal.The vortex signal with high level white noise and harmonic disturbance is analyzed by simulation.The simulation and experiment results indicate that the method based on chaos has a good immunity to ...