The insight into the transient velocity fields (TVFs) is important for the verification of simulations which together with the evaluation of the eddy strength fields (ESFs) provides a better understanding of flame dynamic. Interference fringes pattern of a MeOH-tank-flame were measured by use of a holog. transmitted light interferometer which provides data for the calcn. of TVFs and ESFs by the interference fringes pattern correlation (FPC) anal. The calcd. flow velocities in tank flames are comparable with velocities obtained by other methods. Besides, with this method the TVFs of many tank flames of different fuels can be detd. which can not carried out with other methods such as the particle track laser-sheet method by interference with the visible spectrum of flame radiation.