TsAGI Tests New Pusher Model
10 March 2021
The specialists of the Central Aerohydrodynamic Institute n.a. Prof N.E. Zhukovsky (TsAGI, a part of NRC “Zhukovsky Institute”) performed a test campaign for a pusher located on large-aircraft fuselage model.
Studies of the feasibility to introduce a propulsion system with a pusher propeller instead of a tractor one are due to the urgent task to increase the aircraft internal space and the need to place environmentally friendly fuel inside the fuselage. Such prospects are already being investigated by foreign aircraft developers: the ZeroEmission project by Airbus, EU, or Celera 500L aircraft (Otto Aviation, USA), which already has made its flight.
At first, the specialists of Aerodynamic Propulsion Department developed an optimum-design method applicable both for pusher and tractor configurations. Based on this method, a propeller was designed which was optimized for aircraft-wake stagnant flow.
The advantages of positioning the propeller behind the fuselage or engine nacelle follow from the propeller impulse theory and are confirmed by calculations and numerous experiments. However, there is a downside to this effect that is an increase in the drag of the aircraft as a whole. This is due to decrease in pressure in the tail section due to the running propeller.
"Our task was to find a balance between these phenomena. We needed to increase the thrust and, at the same time to maintain the body streamlining.
We have successfully coped with this and got a good groundwork to create the future aircraft, Vitaly Gubsky, Sc.D., Project Leader, Head of Division (TsAGI) commented the research results.
Designing and manufacturing the pusher, TsAGI specialists managed to obtain the improved thrust-increased noise-reduced configuration. The test results confirmed that the pusher configuration makes it possible to increase the aircraft flight speed and to reduce the power consumption, vs. the propeller in classical tractor configuration.