Abstract: A series model method is adapted to the preliminary study of scale effect of discharge atomization-rainfall (A-R) model with the field observation result of discharge atomization for Wujiangdu power station.The effect of Re and We numbers of flow on the A-R intensity is analyzed.A conversion relationship of A-R intensity between prototype and model results is developed.The similitude criteria of the A-R range followed by discharge atomization model is discussed,and the conclusion is achieved that the surface tension of discharge A-R model is ignored when We number is larger than 500.