A Denoising Method of Vortex Flowmeter Signal in Oscillatory Flow Based on Hilbert Huang Transformation

Hilbert-Huang Transform (HHT) is a new and effective method of analysing nonlinear and nonstationary time series. With this new method any complicated signal could be decomposed into a finite number of Intrinsic Mode Functions (IMFs). In this paper, HHT is applied to the vortex flow signal in oscillatory flow. First, the vortex flow noisy signal is decomposed into several IMFs using the efficient and adaptive Empirical Mode Decomposition(EMD). Then the high-frequency components filtered by EMD-scale are used for de-noising. And finally, a signal is reconstructed with both the high-frequency components after EMD-scale filtering and the low-frequency components. The reconstruction signal is a de-noising signal. This signal simulation test showed that this method to deal with the vortex flow signal in oscillatory flow is easy and effective.