PROJECT TITLE : VARIABLE FLOW FAN
TECHNICAL ABSTRACT (LIMIT 200 WORDS)
A variable flow fan aircraft propulsion system offers the potential for achieving low specific thrust with low jet velocity for low noise for takeoff, side-line, and initial climb, and high specific thrust for climb and acceleration to supersonic cruise. To achieve this, the operating envelope of a variable flow fan has to be expanded over existing turbofan engines. The variable flow fan concept (i.e., the Variable Fan Exit or "VFX") can efficiently operate beyond the usual fan (or compressor stall) line using new methods of scheduling the fan geometry as a function of flight Mach Number, fan pressure ratio and corrected speed, and by utilizing variable inlet guide vanes (IGV's), variable stators, and variable outlet guide vanes (OGV's). The VFX operates on an inverted operating line from high corrected flow, low pressure condition to a high pressure ratio, low corrected flow condition at constant corrected speed. Under this program, parametric design studies will be conducted on the VFX concept to determine the optimum "design" (reference) point, fan geometry schedules (including turn-down-ratio), stator and guide vane aerodynamic design, and number of fan stages.POTENTIAL COMMERCIAL APPLICATIONS
This effort will provide preliminary design of the fan that will go into further developing the VFX engine. The VFX concept in general, will provide improvements in stage efficiency and stall margins, and provide large swings in corrected flow and pressure ratio. When applied to a HSCT or supersonic aircraft, the VFX has a unique advantage over conventional fans in its ability to achieve high by-pass ratios and low jet velocities at takeoff conditions (resulting in lower jet noise), and to achieve low by-pass ratios and high specific thrust levels at transonic acceleration and supersonic cruise. Another important benefit is the low specific fuel consumption (SFC) at subsonic cruise. Additionally, the flexibility of VFX offers improvements in performance and operability of large by-pass turbine engines for commercial aircraft. For military fighter aircraft, the VFX can extend the range and combat capability by eliminating the need for after-burners (resulting in improved performance and SFC and lower infrared (IR) ignature.NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR
NAME AND ADDRESS OF OFFEROR
DIVERSITECH INC.
110 BOGGS LANE, SUITE 325
CINCINNATI, OH 45246