This research is divided in two main sections. The first part is about unsteady state simulation of rivulet liquid film flow over flat and corrugated plate without existing gas phase. Investigation showed liquid film width is rapidly increased when the angle of inclined plate decreased. Maximum liquid film thickness remained constant when the angle of inclined plate changes between 45 and 65 degree. By decreasing contact angle liquid film width and maximum liquid film thickness are increased. Simulations revealed that surface tension had no considerable effect on rivulet flow; also, liquid film width and maximum thickness are changed with varying viscosity. Comparisons between rivulet flow over flat and corrugated plates showed that maximum liquid film velocity and thickness in corrugated plate are more than flat plate but liquid film width is less when the contact angle is less than 24.5 degree. From these results, one may found when the contact angle is small, surface waviness causes increasing liquid velocity and prohibit spreading liquid film over surface. When contact angle is more than 67 degree, liquid film velocity decreased and liquid film width increased. Moreover, maximum liquid film thickness remained nearly constant, therefore, surface waviness causes increasing liquid and gas phase contacting area. In the second part of this thesis, firstly, single phase flow of air through a complete element of Flexipac 1Y is simulated at steady state using CFD method. After that, the flow of air-water is simulated in Flexipac 1Y to investigate hydrodynamics of two-phase flow. During these simulations, four different turbulent models are tested and found k-? base model is the most appropriate turbulent model for simulation of hydrodynamics in structured packing. CFD analysis is used to simulate simultaneously momentum, mass and heat transfer in a binary mixture of Cyclohexane-n-Heptane distillation in structured packing. At the end, four different turbulent models are used for simulation and found again k-? base model is the best choice for simulation of turbulence in a complex geometry of structured packing.
