A new concept in wind power harnessing is recently developed under INVELOX (Increasing VELocity) by the company Sheerwind in USA. It is claimed that the new concept can significantly outperforms traditional wind turbines in terms of reducing the diameter of wind turbine, improve aerodynamic characteristics under the same wind conditions, and delivers significantly higher output at reduced cost. The innovative feature of the wind turbine is the elimination of tower-mounted turbines. It is believed that the entry of such systems is crucially important because external flows over nozzle or diffuse devices are different from classically known internal flows. Shrouded wind turbines and wind catcher systems are normally use a diffuser shape at entry, however, the INVELOX concept suggest using a nozzle at entry. In this paper, two different simpler systems than INVELOX are designed with nozzle or diffuser at the entry using general methods in design of blower wind tunnels. In the first phase of this work, CFD (computational fluid dynamics) method is applied to solve external flows around nozzle and diffuser flows by solving the modelled RANS (Reynolds average Navier-Stokes) equations. The initial results indicate that the wind speed retarded at the entry of nozzle while wind speed accelerated at entry of a diffuser device.