To realistically treat the poly-dispersed soot formation system, the Direct Quadrature Method of Moment (DQMOM) in conjunction with the transient flamelet approach was adopted to simulate a turbulent non premixed C2H4/air flame. The population balance equation of the soot particle distribution was approximated using the multi-environment probability density function which consists of multiple weights and abscissas in the physical space. The transient flamelet model was employed to treat the turbulence chemistry interactions and the two-equation soot model was used to account for the soot/gas chemistry coupling allowing mass and energy exchange. In the framework of the transient flamelet model, the physical soot model terms such as nucleation, surface growth, and oxidation for the population balance equation of soot particle distribution were closed. In terms of the mean temperature, soot volume fraction, primary soot particle number density, primary soot aggregate number density, mean number of primary particle per aggregate, mean radius of soot aggregate, and mean primary soot particle diameter, the predicted profiles agreed reasonably well with the experimental data. (C) 2016 Elsevier Ltd. All rights reserved.