The characteristic of the concentration wave in the RTD of out-circular reactor

which is a nonstationary quasi-periodic signal

has been investigated with wavelet analysis.At first

the characteristic scale of concentration wave was determined with an energy maxima criterion based on wavelet analysis.And we found that the characteristic scale of concentration wave is about directly proportional to the average once through time of the reactor.Then

a reconstruction formula based on wavelet analysis is strictly proved to be capable of reconstructing the concentration wave shape.At last

the local singularity exponents of concentration wave crests are calculated with wavelet analysis.The results show that the local singularity exponents of crest increase with time

and runs to about 2 0

which agree very well with theoretical result.