CN-121716888-B - Flexible variable casing regulation and control method considering multi-state power matching requirements of electric propulsion ducted fan

CN121716888BCN 121716888 BCN121716888 BCN 121716888BCN-121716888-B

Abstract

The invention provides a flexible variable casing regulating and controlling method considering multi-state power matching requirements of an electric propulsion ducted fan, and relates to the technical field of aviation electric propulsion. The method comprises the steps of receiving incoming flow conditions, thrust requirements and power constraint of an electric propulsion ducted fan, determining the throat radius of a flexible variable casing arranged in an inner flow channel at the downstream of a stator of the electric propulsion ducted fan, and changing the profile of the flexible variable casing by regulating and controlling the internal and external pressure difference of the flexible variable casing so as to regulate and control the working condition and power of the electric propulsion ducted fan, thereby meeting the multi-state power matching requirement of the electric propulsion ducted fan. The invention solves the problems of complex structure, great difficulty in actuation and control and the like of the existing nozzle adjusting scheme, and can effectively improve the multi-state comprehensive performance of the electric propulsion ducted fan.

Inventors

ZHANG BOTAO
YIN SONG
LIU ZHICHENG
WU CHAO
PU HONGBING

Assignees

太行国家实验室

Dates

Publication Date: 20260505
Application Date: 20260225

Claims (9)

1. A flexible variable casing regulation and control method considering multi-state power matching requirements of an electric propulsion ducted fan is characterized by comprising the following steps: Obtaining incoming flow conditions of the electric propulsion ducted fan, wherein the incoming flow conditions comprise incoming flow total pressure p t0 , static pressure p 0 , total temperature T t0 and Mach number Ma 0 signals; determining the constraint power P of the electric propulsion ducted fan in the current state according to the incoming flow condition and the total required thrust F; determining the working condition of an electric propulsion ducted fan according to the required thrust F and the constraint power P, and determining the required area and the required radius R4 of the throat of the flexible variable casing; Acquiring an upstream casing inner flow path static pressure p4 signal of the flexible variable casing, adjusting a flexible variable casing outer cavity static pressure pa, and determining an actual radius R41 of a flexible variable casing throat according to the upstream casing inner flow path static pressure p4 signal and the outer cavity static pressure pa; Judging whether the actual radius R41 of the throat of the flexible variable casing is equal to the required radius R4 in the current state, if so, calculating the actual power P1 of the electric propulsion ducted fan in the current state, otherwise, acquiring a static pressure P4 signal of an upstream casing inner flow channel of the flexible variable casing again and adjusting a static pressure pa of an outer cavity of the flexible variable casing until the actual radius R41 of the throat of the flexible variable casing is equal to the required radius R4; Judging whether the actual power P1 of the electric propulsion ducted fan in the current state is smaller than or equal to the constraint power P, if so, fixing the static pressure pa of the outer cavity of the flexible variable casing, and finishing regulation and control of the flexible variable casing in the current state, if not, re-determining the working condition and the required radius R4 of the electric propulsion ducted fan, re-regulating the profile of the flexible variable casing to enable the actual radius R41 of the throat to be equal to the required radius R4, and calculating the actual power P1 again until the actual power P1 is smaller than or equal to the constraint power P, and finishing regulation and control of the flexible variable casing, and outputting the profile geometry of the flexible variable casing, the actual power and the actual thrust of the electric propulsion ducted fan after the regulation and control are finished.
2. The flexible variable casing regulating and controlling method considering multi-state power matching requirements of an electric propulsion ducted fan according to claim 1, wherein the actual power P1 of the electric propulsion ducted fan in the current state is calculated by the following formula: Wherein m is the mass flow of the electric propulsion ducted fan, the unit is kg/s, c p is the specific heat capacity of air, the unit is J/(kg.K), T t5 is the total temperature of the outlet of the electric propulsion ducted fan, the unit is K, and T t0 is the total temperature of incoming flow, and the unit is K.
3. The flexible variable casing regulating method considering multi-state power matching requirements of an electric propulsion ducted fan according to claim 1, wherein the actual thrust F1 of the electric propulsion ducted fan is calculated by the following formula: Wherein m is the mass flow of the electric propulsion ducted fan, the unit is kg/s, V 0 is the incoming flow speed, V 5 is the outlet speed of the electric propulsion ducted fan, the unit is m/s, A 5 is the outlet area of the electric propulsion ducted fan, the unit is m 2 ;p 5 is the outlet static pressure of the electric propulsion ducted fan, the unit is Pa, and p 0 is the incoming flow static pressure, and the unit is Pa.
4. The flexible variable casing regulating and controlling method for considering the multi-state power matching requirement of the electric propulsion ducted fan according to claim 1, wherein the electric propulsion ducted fan comprises a ducted body, a flexible variable casing outer cavity, a suction pipeline, a control valve, a vacuum pump, a rotor, a stator, an air inlet cone, a driving motor, an exhaust cone and an outlet total temperature-total pressure composite comb probe; The duct body is positioned at the periphery of the rotor, the duct body flow passage at the downstream of the stator is provided with the flexible variable casing, the outer side of the flexible variable casing is a flexible variable casing outer cavity, the flexible variable casing outer cavity is connected with the suction pipeline and the vacuum pump, the suction pipeline is provided with a control valve, the rotor is mechanically connected with the driving motor through a transmission shaft, the air inlet cone is connected with the rotor, the air outlet cone is arranged at the downstream of the driving motor and the duct body, and the outlet of the duct body is provided with the outlet total temperature-total pressure composite comb-shaped probe.
5. The flexible variable casing regulating and controlling method considering multi-state power matching requirements of an electric propulsion ducted fan according to claim 1, wherein the flexible variable casing is made of intelligent composite materials driven by differential pressure, so that the inner runner profile of the flexible variable casing is a continuous and smooth sine function under the drive of differential pressure.
6. The flexible variable casing regulating and controlling method considering multi-state power matching requirements of the electric propulsion ducted fan according to claim 1, wherein a static pressure measuring hole is arranged in an upstream casing inner flow path of the flexible variable casing and is used for measuring an upstream casing inner flow path static pressure p4 of the flexible variable casing.
7. The flexible variable casing regulating and controlling method considering multi-state power matching requirements of an electric propulsion ducted fan according to claim 1, wherein the position with the minimum radius of the flexible variable casing is a flexible variable casing throat, the actual radius R41 of the flexible variable casing throat is 0.90Rs < R41 < 1.02Rs, and Rs is the radius of the flexible variable casing throat when the pressure difference between the inside and the outside of the flexible variable casing is zero.
8. The flexible variable casing regulating and controlling method for considering multi-state power matching requirements of an electric propulsion ducted fan according to claim 1, wherein the length L of the flexible variable casing is 0.10Rs less than or equal to L less than or equal to 0.40Rs, wherein Rs is the radius of the throat of the flexible variable casing when the internal and external pressure difference of the flexible variable casing is zero.
9. The flexible variable casing regulation and control method considering multi-state power matching requirements of the electric propulsion ducted fan according to claim 4 is characterized in that the outlet total temperature-total pressure composite comb probe is a radial 5-point comb probe and is distributed in an equal annular surface in the radial direction, the total pressure probe of the outlet total temperature-total pressure composite comb probe is a three-hole probe, and the outlet total pressure p t5 , the static pressure p 5 and the flow velocity V 5 of the electric propulsion ducted fan are obtained by processing and calculating data measured by three pressure measuring holes.

Description

Flexible variable casing regulation and control method considering multi-state power matching requirements of electric propulsion ducted fan Technical Field The invention relates to the technical field of aviation electric propulsion, in particular to a flexible variable casing regulating and controlling method considering the multi-state power matching requirement of an electric propulsion ducted fan. Background Under the development drive of aircrafts such as full electricity/hybrid electricity and new energy aircrafts, an electric propulsion ducted fan becomes one of main propulsion devices of a distributed propulsion system, and has received high attention in recent years. Compared with a propeller, the electric propulsion ducted fan benefits from the capturing and organization effect of the ducted lip on the airflow, so that the electric propulsion ducted fan can provide high-quality air intake for the rotor, and can generate larger thrust or lifting force compared with the propeller with the same diameter under the same input power. Meanwhile, the inclusion duct body of the electric propulsion duct fan provides physical safety protection and limits noise level, so that the electric propulsion duct fan meets the development targets of green, efficient and safe future aviation. The ratio of the ground and the thrust of the high-speed electric propulsion ducted fan for the horizontal take-off and landing aircraft exceeds 7, is more than 12 compared with the ratio of the vertical hovering and the horizontal cruising of the electric propulsion ducted fan for the vertical take-off and landing aircraft, is far higher than the state of a fan/air compressor in a traditional turbofan engine, and the excessive thrust difference causes that the electric propulsion ducted fan possibly works in the limit working conditions such as deep blockage, near stall and the like in the stages of ground, climbing, cruising or hovering and the like, so that the matching efficiency of the electric propulsion ducted fan is influenced, and the electric propulsion ducted fan faces the matching problem of the thrust, the power and the pneumatic performance under multiple states. In order to realize multi-state power matching, the electric propulsion ducted fan needs to realize flow matching under multiple states through geometric adjustment and other ways. Compared with a propeller, the electric propulsion ducted fan rotor has higher pneumatic load and rotating speed, smaller size and volume, and the realization difficulty of a similar propeller 'variable pitch' technology on the small-size high-load electric propulsion ducted fan rotor is large. For this reason, the electrically propelled ducted fans typically employ adjustable nozzles to achieve multi-state matching, such as by employing "variable nozzle" measures to effectively increase the aerodynamic efficiency of the ducted fan in cruise and hover conditions. The spout is adjusted through complicated adjustment mechanism and structural design to the measure, and the spout adjusting device comprises a sealing structure, a movement mechanism, an adjusting piece, a hydraulic actuating system and other designs, and has the advantages of high structural design, high accuracy, high robustness, high adjustment and control difficulty and high cost, and meanwhile, the weight of the system structure is obviously increased, and the integral performance is not facilitated. Disclosure of Invention In view of the above, the embodiment of the application provides a flexible variable casing regulating and controlling method for considering the multi-state power matching requirement of an electric propulsion ducted fan, which realizes the effective circulation and the pneumatic state regulation of the electric propulsion ducted fan by actively and intelligently regulating and controlling the molded surface of the flexible variable casing under different states, thereby achieving the purpose of multi-state power matching of the electric propulsion ducted fan. The embodiment of the application provides a flexible variable casing regulating and controlling method considering the multi-state power matching requirement of an electric propulsion ducted fan, which comprises the following steps of: Obtaining incoming flow conditions of the electric propulsion ducted fan, wherein the incoming flow conditions comprise incoming flow total pressure p t0, static pressure p 0, total temperature T t0 and Mach number Ma 0 signals; determining the constraint power P of the electric propulsion ducted fan in the current state according to the incoming flow condition and the total required thrust F; determining the working condition of an electric propulsion ducted fan according to the required thrust F and the constraint power P, and determining the required area and the required radius R4 of the throat of the flexible variable casing; Acquiring an upstream casing inner flow path static pressure p4 signal of th