This thesis presents simulation results of a pilot scale cracking reactor. The reactor converts a mixture of aromatic and non-aromatic compounds to middle distillate products, diesel and kerosine. By progressing of reactions undesired products of naphtha and gas are produced. Velocity distribution of the feed, pressure and temperature have a great impact on concentrations of diesel and kerosine as desirable products. Modeling and simulation of flow field in combination with kinetic model can provides more detailed information on the system in comparison with a simple kinetic model. Computational Fluid Dynamics simulation method as a new method for estimation of the components concentration distribution in hydrocarbon hydrocracking reactor studied. Application software of Gambit 2.3 and CFX 11 are used and model of the packed bed reactor, in order to have information on flow lines and velocity vectors, and the distribution of concentration for various liquid space velocities, and different operating temperatures along the reactor. Dimensions, operating conditions and the reaction’s kinetic model were based on a pilot scale reactor in RIPI, Tehran
