Usenko V. Method for calculating acoustic loss of the coaxial propeller fan in the energy balance of the aircraft power plant

Method for calculating acoustic loss of the coaxial propeller fan in the energy balance of the aircraft power plant has been developed for the first time. The developed method makes it possible to estimate the contribution of acoustic loss in the overall energy balance, and also makes it possible to estimate the change in fuel economy when carrying out measures to reduce the noise level of the propfan. The recommendations have been provided for determining appropriate ratio of the diameters of the first and the second rows of the coaxial propeller fan, rotational speed ratio of the first and the second rows of the coaxial propeller fan, appropriate number of blades of the first and the second rows of the coaxial propeller fan in order to reduce acoustic emission of the propeller fan. The recommendations have been provided for increasing fuel efficiency of the turbopropfan engine due to reducing acoustic emission of the coaxial propeller fan.