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Advances in Aircraft and Spacecraft Science Volume 5, Number 3, May 2018 , pages 349-362 DOI: https://doi.org/10.12989/aas.2018.5.3.349 |
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Numerical simulation of the unsteady flowfield in complete propulsion systems |
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Michele Ferlauto and Roberto Marsilio
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| Abstract | ||
| A non-linear numerical simulation technique for predicting the unsteady performances of an air-breathing engine is developed. The study focuses on the simulation of integrated propulsion systems, where a closer coupling is needed between the airframe and the engine dynamics. In fact, the solution of the fully unsteady flow governing equations, rather than a lumped volume gas dynamics discretization, is essential for modeling the coupling between aero-servoelastic modes and engine dynamics in highly integrated propulsion systems. This consideration holds for any propulsion system when a full separation between the fluid dynamic time-scale and engine transient cannot be appreciated, as in the case of flow instabilities (e.g., rotating stall, surge, inlet unstart), or in case of sudden external perturbations (e.g., gas ingestion). Simulations of the coupling between external and internal flow are performed. The flow around the nacelle and inside the engine ducts (i.e., air intakes, nozzles) is solved by CFD computations, whereas the flow evolution through compressor and turbine bladings is simulated by actuator disks. Shaft work balance and rotor dynamics are deduced from the estimated torque on each turbine/compressor blade row. | ||
| Key Words | ||
| propulsion system simulation; gas-turbines; compressible flows; CFD | ||
| Address | ||
| Michele Ferlauto and Roberto Marsilio: Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Cors Duca degli Abruzzi, 24, 10129, Torino, Italy | ||
