In order to determine the quality of mixing in TBIM, the mass
fraction of methane (Mch4) throughout the axial length of TBIM
was investigated using the histogram as shown in Fig. 4.
During the investigation, Mch4 with the highest frequency (Mhf)
was retrieved from each histogram. The closer the Mhf to the
Mch4.s, the better the mixing quality obtained and vice versa.