Extracting Coherent Structure from Temperature Data in Rayleigh-Bénard Convection by Wavelet Transformation
Qiang Fu, Pla Uni · Journal of PLA University of Science and Technology · 2001
In this paper,wavelet transformation is used to analysis the temperature signals in Rayleigh-Benard convection.By means of the criterion,i.e.the variance of coefficient of wavelet transformation reaches maximum at a given scale,the corresponding scale or frequency of coherent structure can been obtained automatically.Based on a new reconstruction (or inverse) formula at this scale,the coherent structure can be extracted successfully and no threshold is added.In order to prove the validity of this method,one numerical test,to extract coherent structure from a known signal which is composed of cosine+noisesignal,has been accomplished.The results show that the coherent structure involving the signals can be well extracted by using this method.