Diesel engines are the main source of NOx emissions. One of the best ways to control the NOx released by these engines is exhaust gas recirculation (EGR) systems. Among the types of these systems, the cool EGR system performs better than other systems. The deposition of soot particles in these systems and the evolution of fouling porous layers (EFPL) affect the performance of these coolers. Therefore, the effect of EFPL has been investigated in the present study as a constant thickness, Evolution uniformly, and simulation with particle deposition using the Boltzmann method (LBM). The effect of two pertinent dimensionless parameters, namely Darcy number (10^(-4)≤Da≤5×10^(-3)) and Reynolds number (100≤Re≤400), on the time history of the fouling layer growth decline of thermal performance of the duct and average Nusselt number ratio (〖Nu〗_r=〖Nu〗_av⁄(〖Nu〗_av (t=0) )) is studied. The results show the decline of 〖Nu〗_r divided into two parts. The first part is the initial stage; in this stage, the duct acts like an empty duct and 〖Nu〗_r remains constant. The second stage is the evolution stage; in this stage, the drop of 〖Nu〗_r occurs with an almost constant slope. The evolution time decreases as the Darcy number decreases and the Reynolds number increases. Also, the correlations for evolution time in terms of Darcy and Reynolds numbers and 〖Nu〗_r in terms of elapsed time and Darcy and Reynolds numbers have been presented. Simulation of the EPFL generated by particle deposition shows the two mentioned stages. After a while, the change in the thickness of the layer and a drop in 〖Nu〗_r is not observed. This time is called the steady fouling layer (SFL) time. The reason for the occurrence of this phenomenon is the reduction of the thermophoresis force as the main factor in particle deposition in these coolers due to the thermal resistance created by EPFL.