The goal of the project is to increase the efficiency of the innovative propulsion unit for small airplanes. The innovation of the propulsion unit that is currently being developed is in replacing the standard propeller with a fan stage installed in an air duct inside the fuselage of the airplane.
The complete propulsive unit consists of an inlet channel, fan stage with a stator stage and a piston engine run by a rotor, outlet channel with a cooling by-pass and a nozzle.
Because of the subsonic flow inside the propulsive unit it is impossible to design individual parts of such a complex device independently. It is necessary to use the iterative algorithms, which will take them into consideration. In spite of the detailed development, only after the extented development and functional experiments on the real device and in real operating conditions (e.g. test of the propulsive unit in a real fuselage in a wind tunnel) it was possible to evaluate the efficiency of the set and define activities to increase the efficiency.
The goal of the project, based on the experience gained in tests of the functional sample, is to increase the efficiency of the individual parts of the propulsive unit and the total efficiency in order to maximally shorten the time between the test flights of the prototype and the repeated production of the aiplane.
The main steps of the project are as follows:
It is especially:
- optimization of the inlet channel in order to obtain maximum uniformity of the flow field in front of the fan stage, minimize losses in the total pressure and minimize drag of the airplane
- design of the blading geometry respecting the influence of the flow field at the output from the inlet channel, the pressure loss in the back of the fan and the real parameters of the drive unit
- test of the applicability of the drive unit with better installement parameters and higher reliability
- optimization of the shape of te outlet channel, especially the shape of the cooling by-pass, in order to better use the waste heat.