Concepts Developed for a Multi-Phased, Vertical Axis Wind Turbine System With an Adjustable Inlet Air Scoop and Exit Drag Curtain

Abstract

A conceptual design is presented of a roof-top type, MULTI-PHASED VERTICAL AXIS WIND TURBINE SYSTEM with an ADJUSTABLE INLET AIR SCOOP and EXIT DRAG CURTAIN at a 100 Watt to 50 kWe commercial scale. The MULTI-PHASED VERTICAL AXIS WIND TURBINE (MVAWT) SYSTEM is cost effective in an environmentally friendly manner. It is especially useful in areas where it can benefit from the wind velocity increasing and streamlining effects that may occur around small hills, roof tops and tall buildings. The MVAWT system concentrates, collects and utilizes the available energy in the wind by way of a naturally yawed, downwind seeking, vertical axis orientated flow tube and integrated air turbine assembly with adjustable inlet air scoop and outlet drag sections mounted on the flow tube. The MVAWT system’s air turbine is a combination radial or mixed out-flow and reaction cross-flow type centrifugal fan design as mounted on the discharge end of the flow tube. This air turbine, being more of a radial instead of an axial flow or propeller type design, can potentially exceed the Betz limit of 59.26% energy recovery or effectiveness from the maximum energy available from the wind flowing through the inlet flow tube. A low pressure drop screen can be provided at the inlet and outlet to protect flying birds and mammals from being drawn into the integrated flow tube and air turbine assembly. Additionally, access to the rotating components for inspection and maintenance purposes is much safer, easier and less costly than with conventional propeller type wind turbine systems mounted on tall towers. No multiple staged wind turbine system as described herein has as yet been researched as to its technical feasibility and developed to the point of a prototype demonstration at a commercial size. Such parameters as overall performance, energy conversion efficiency, costs (installed, operating and maintenance), system reliability, public acceptance and environmental impacts have not yet been truly assessed. A Phase I - technical feasibility assessment and Phase II - prototype demonstration program for a nominal 10 kWe sized Multi-Phased Vertical Axis Wind Turbine system with an average power output in a 16 mph wind of as much as 2 kWe (kW-hr / hr) and as much as 10 kWe (kW-hr / hr) at a 28 mph wind velocity is suggested to provide this essential information to both the authors and the public at large.