Device for assisting with regulation of propellers of aeronautical turbomachinery
This control device for a propulsion system, comprising means for calculating a blade-pitch setpoint of at least one propeller of the propulsion system, the calculation means using a performance predictive model of the propeller taking account of at least one flight speed for adapting a blade-pitch angle setpoint, is characterised in that the performance predictive model of the propeller is configured to use polar charts implemented in the form of a mathematical law.
1 . A turboprop engine comprising:
an actuator configured to control a blade pitch; and
control device for a propulsion system, the control device comprising one or more processors, wherein the one or more processors are configured to determine a blade-pitch setpoint of at least one propeller of the propulsion system using a performance predictive model of the propeller taking account of at least one flight speed for adapting a blade pitch angle setpoint,
wherein the performance predictive model of the propeller is configured to use polar charts implemented in the form of a mathematical law, comprising:
a first polar diagram giving a lift coefficient as a function of angle of incidence, relative Mach number, and a ratio between flight speed and peripheral speed of the propeller; and
a second polar diagram giving a drag coefficient as a function of the lift coefficient, the relative Mach number, and the ratio between the flight speed and the peripheral speed of the propeller,
wherein the actuator is configured to adapt the blade pitch depending on a difference between a measured instantaneous blade pitch angle and the blade pitch angle setpoint.
2 . The turboprop engine according to claim 1 , wherein the propulsion system comprises at least one element selected from among a rotor, a stator, an upstream rotor and a downstream rotor counter-rotating with respect to the upstream rotor, and a rotor and stator assembly, the rotor being located upstream of the stator.
3 . The turboprop engine according to claim 1 , wherein the performance predictive model of the propeller takes account of a measurement of the rotational speed of the propeller and a measurement of the mechanical torque of the shaft of the propeller.
4 . The turboprop engine according to claim 1 , wherein the performance predictive model of the propeller uses an optimisation mathematical law to define a blade-pitch setpoint for at least one stator.
5 . The turboprop engine according to claim 1 , wherein the one or more processors are configured to perform an iteration loop, a stop criterion of which is the convergence of a lift coefficient from a calculated value towards a value obtained by using the polar charts.
6 . The turboprop engine according to claim 1 , wherein the one or more processors are configured to perform an iteration loop having a stop criterion determined based on a convergence from a calculated value of the mechanical torque towards the measured mechanical torque.
7 . The turboprop engine according to claim 1 , wherein the polar charts are obtained by using a reset of the mathematical formulation with regards to target results obtained by three-dimensional numerical simulation or by wind tunnel tests.
8 . The turboprop engine according to claim 1 , wherein said device forms a module for a full-authority digital electronic controller.
9 . The turboprop engine according to claim 1 , further comprising a full-authority digital electronic controller comprising the control device.
10 . An aircraft comprising a turboprop engine according to claim 1 .
11 . A method for controlling a propulsion system of a turboprop engine, comprising:
determining, by one or more processors, a blade-pitch setpoint of at least one propeller of the propulsion system, during which a step of predicting the performance of the propeller is performed taking account of at least one flight speed to adapt a blade-pitch angle setpoint, said prediction step being characterised by the use of the polar charts implemented in the form of a mathematical law, comprising:
a first polar diagram giving a lift coefficient as a function of angle of incidence, relative Mach number, and a ratio between flight speed and peripheral speed of the propeller; and
a second polar diagram giving a drag coefficient as a function of the lift coefficient, the relative Mach number, and the ratio between the flight speed and the peripheral speed of the propeller; and
adapting, by an actuator, a blade pitch of the turboprop engine depending on a difference between a measured instantaneous blade pitch angle and the blade pitch angle setpoint.