Wavelet-based optical velocimetry: an alternative technique for deepwater oil spill flow rate estimation

Abstract

Deepwater oil spill flow rate estimation is a challenge due to the lack of dedicated techniques. As well as the complex nature flow associated with oil jet leads to inaccurate flow rate estimation. In this paper, a novel technique based on discrete wavelet transform was developed. Wavelet transform has the advantage of decomposing signals into numerous levels. This could be useful for flow estimation of the complex signals of oil jet. The jet flow signals were decomposed using discrete wavelet decomposition (DWT), and then the flow was estimated using Fast Fourier Transform (FFT) cross correlation algorithm. The technique was called DWT-FFT. To validate the DWT-FFT, a turbulent jet flow was experimentally simulated by changing the jet nozzle Reynolds number from 1847 to 11656. The DWT-FFT estimated the nozzle velocity with an error of 34.8%. However, the DWT-FFT is sensitive to wavelet decomposition level and has less sensitivity to the selection wavelet function.