The wake interaction phenomenon among wind turbines has a great influence on aerodynamic power output, wind speed deficit turbulence stress and wake vortex structure, which indicates that more attention should be placed on the wake interaction for the optimal arrangement of wind farm. In this present study, firstly a numerical validation of aerodynamics for the two offset model wind turbines using actuator line model and CFD technique. The results obtained from the present simulations are compared to the data from the experiment “Blind Test 3” and other simulation models. Based on the simulations results, the present study shows good agreement with the experimental results. Then considering the uniform inflow condition, the complex phenomenon of wake interaction in wind farm containing fourteen wind turbines is simulated using a numerical method. Large eddy simulations combined with an actuator line model are conducted in the in-house CFD code FOWT-UALM-SJTU Solver. The motivation for this work is to create a sound methodology for performing the simulation of large wind farms. To better understand the wake interaction phenomenon, the aerodynamic power coefficients and basic features of both the near and far wake, including the distribution characteristics of the mean wake velocity and vortex structures are studied in detail.