Periodic Reporting for period 2 - CS2-WP714-DE (Advanced Design of Very High Power Density Piston Engine and Thermal Management Challenges for Aircraft Application)
Reporting period: 2017-08-01 to 2019-06-30
The main objective of this project is to improve the power density of the engine, by reducing its weight and confirming its power capabilities, based on SAE SR305 4-cylinder engine return of experience.
On the basis of the existing combustion chamber and piston from SR305 engine, Danielson Engineering and DFM Europe will improve the design of the whole engine, taking into account thermo-mechanical loads, weight considerations and up-to-date materials. Furthermore, the engine cooling system will be designed to increase the engine performances and reliability, integrating the specific requirements of an aeronautical application (safety, fire resistance, environment compliance and resistance…).
At the end of the action, 4 prototype enhanced engines are available and reach the objectives defined in terms of power density and reliability.
The batch sets of prototype parts have been manufactured and inspected before the assembly of the engines.
After an oil pump failure that has been solved, four engines were debugged and then run-in, reaching a maturity and reliability levels in accordance with the commitments made with CS2.
Further, the development of the SR460 enhanced engine could eventually be pursued by SAE, especially by conducting tests on propeller benches, more representative of the actual operating conditions of an aircraft engine.
Concerning DFM, work done first addressed thermal management under-the-wood thermal; the latter was achieved from the DFM-Europe dedicated software DOFI. The latter is based on opensource and provides a new CFD software able to deal with full coupled and massive parallel approach. Heat transfer system has been simulated and efficiency may be still gain to enhance thermal exchange especially in aircraft engine.
The fundamental contribution of DFM is the demonstration of the use of mechanical vibration as a potential source of increased heat transfer. Such source is “free” in aircraft engine and actuators provide vibrations that enhance heat transfer from thermal boundary-layer disruption.