In the present work a 1D plug flow evaporator has been considered to study the evaporation, atomization and transport of polydisperse droplets in a pulsating air stream. The pulsation in the air flow is very common in the real combustor due to the thermo acoustic instabilities. Population balance modeling approach is used to study the continuous evaporation and atomization process. An Eulerian-Eulerian multiphase framework is used to capture the polydispersity of the system. For the evaporation the fixed drop size methodology of the D2 law has been used whereas, for the atomization the conservation of mass has been considered during the breakage. The objective of this work is to study the pulsation frequency on the dispersion of droplets without and with presence of the evaporation and atomization rate. From the results, clustering of particles in different locations has been identified. The variation of Sauter Mean Diameter (SMD) is presented and the non-linear behaviour has been identified in the process. Copyright © 2014 by ASME.