CN117034451A

CN117034451A - Rotor/propeller aerodynamic disturbance calculation method

Info

Publication number: CN117034451A
Application number: CN202310945805.2A
Authority: CN
Inventors: 祁辉; 陈仁良
Original assignee: Nanjing University of Aeronautics and Astronautics
Current assignee: Nanjing University of Aeronautics and Astronautics
Priority date: 2023-07-31
Filing date: 2023-07-31
Publication date: 2023-11-10

Abstract

The invention discloses a rotor/propeller aerodynamic disturbance calculation method, which comprises the following steps: calculating aerodynamic force and aerodynamic moment of the rotor wing/propeller to form a low-precision high-efficiency calculation model; and (3) calculating aerodynamic force and aerodynamic moment of the engine body component, and establishing a double-propeller propulsion compound helicopter flight mechanics mechanism model. Calculating aerodynamic and aerodynamic moments of the rotor/propeller and establishing a CFD calculation model of the double-propeller propulsion composite helicopter, wherein the momentum source model uses a low-precision high-efficiency calculation model to calculate the descent gradient in the rotor/propeller balancing process, so as to realize rotor/propeller balancing. On the basis of rotor/propeller balancing, the aerodynamic force and aerodynamic moment are corrected by using a full-machine CFD high-precision model and the full-machine balancing is performed by operating, so that a balancing result with high confidence is obtained, and meanwhile, the rotor/propeller aerodynamic interference in a balancing state is obtained. The invention has the advantages that: accurate trimming calculation and interference calculation can be realized, the calculation time is short, the efficiency is high, and the universality is good.

Description

Rotor/propeller aerodynamic disturbance calculation method

Technical Field

The invention relates to the technical field of aerospace, in particular to a calculation method of rotor wing/propeller aerodynamic disturbance of a double-propeller propulsion compound high-speed helicopter in a stable flight state.

Background

To improve the shape of the front flight speed limitation of the traditional helicopterIn condition, new helicopter configurations suitable for high-speed flight are continuously developed at home and abroad. The composite high-speed helicopter designed by adopting the concepts of lift force composite and thrust force composite delays the characteristics of shock waves and stall of backward blades when the rotor wing advances, and has the advantages of vertical take-off and landing of the helicopter and high-speed flight of the fixed-wing aircraft ^[1] . The helicopter is provided with the installed wings on two sides of the traditional fuselage, and a pair of propellers are respectively installed at the front edge of the wings, so that the helicopter can fly forward at a high speed through propeller pitch change, and the lift force generated by the wings can unload the rotors when flying forward at the high speed ^[2-4] . However, due to the fact that aerodynamic components are more and the layout is compact, including a rotor, a left propeller, a right propeller, a wing and the like, when hovering and flying forward at a low speed, a rotor wake can directly impact on a fuselage, the wing and the propeller to cause aerodynamic changes of the components, and in turn, the aerodynamic changes of the components cause the aerodynamic changes of the rotor, so that aerodynamic interferences among the components, particularly the interferences among the rotor and the propeller, seriously affect the flight performance and the flight quality of the helicopter.

The traditional helicopter with single rotor wing and tail rotor has a great deal of wind tunnel data and pilot flight data at present ^[5-7] The mechanism model with high confidence coefficient can be built based on the interference factor of the test data, so that a high-precision trimming result can be obtained. However, as a new-configuration helicopter, the double-propeller propulsion composite high-speed helicopter lacks wind tunnel data and test flight data at present, and influences the confidence of a flight dynamics model. The CFD method can be used as a method for calculating aerodynamic force with high fidelity to obtain a balancing result with high confidence, but because the aerodynamic force of each component of the helicopter is complex in aerodynamic interference, the aerodynamic force of the rotor wing and other components are nonlinear and have coupling in different directions, the calculation of the helicopter balancing Jacobi matrix in the CFD model or the direct searching of the balancing result can cause excessive calculation times and low calculation efficiency. Document [8 ]]Provides a balancing method suitable for a coupling flight mechanics model and a CFD model of a helicopter with a single rotor wing, and the literature [9 ]]A balancing method for a double-propeller propulsion compound high-speed helicopter is provided, but no pneumatic method between components is involvedInterference.

Reference to the literature

[1] Yang Yang the compound high-speed unmanned helicopter has modeling and control strategy research [ D ]. Nanjing aviation aerospace university, 2021;

[2]BUHLER M,NEWMAN S.The aerodynamics of the compound helicopter configuration[J].The Aero-nautical Journal,1996,100(994)；111-120；

[3]PROUTY R W.Helicopter performance,stability and control[M].Malabar,FL:Krieger Publish Company,1990；

[4]ORCHARD M,NEWMAN S.The fundamental configuration and design of the compound helicopter[J].Journal of Aerospace Engineerin-g,2003,217(6):297-315；

[5]Datta A,Yeo H,Norman T R.Experimental Investigation and Fundamental Understanding of a Slowed UH-60A Rotor at High Advance Ratios[C].American Helicopter Society International Annual Forum.2011；

[6]Biedron L R R T.FUN3D Airload Predictions for the Full-Scale UH-60A Airloads Rotor in a Wind Tunnel[J].2013；

[7]Shinoda P M,Yeo H,Itss R,et al.Rotor performance of a UH-60rotor system in the NASA Ames 80-by 120-Foot Wind Tunnel[J].Journal of the American Helicopter Society,2004,49(4).DOI:10.4050/JAHS.49.401；

[8] Feng Deli, qijian Xu Guohua helicopter front flight status balancing analysis based on CFD method [ J ]. Aviation journal 2013,34 (10): 2256-2264;

[9] ni Ming double-propeller propulsion compound helicopter mixing balancing method [ D ]. Nanjing university of aviation aerospace, 2022;

[10] chen Renliang, li Pan, wu Wei, etc. helicopter flight dynamics mathematical modeling problem [ J ]. Aviation journal, 2017,38 (07): 6-22;

[11] zhu Mingyong, innovative, wang Bo helicopter rotor ground effect simulation based on CFD and hybrid balancing algorithm [ J ]. Aviation journal 2016,37 (08): 2539-2551.

Disclosure of Invention

The invention provides a rotor/propeller aerodynamic disturbance calculation method, which solves the following technical problems:

1) How to obtain the high-efficiency high-precision aerodynamic interference of the double-propeller propulsion compound type high-speed helicopter rotor/propeller.

The double-screw propeller propulsion compound high-speed helicopter adopts double screw propellers to replace rotor reaction torque when a tail rotor of a conventional helicopter hovers in balance at a low speed, and the aerodynamic interference of the double screw propeller propulsion compound high-speed helicopter is essentially different from that of the rotor/tail rotor of the conventional helicopter. The double propellers are positioned below the rotor wings and are directly influenced by the wake flow of the rotor wings, and the influence degree changes along with the change of the flying speed. The invention provides a high-efficiency high-precision analysis method for rotor/propeller aerodynamic interference, which is used for determining the rotor/propeller aerodynamic interference of a double-propeller propulsion compound high-speed helicopter in different steady-state flight states and the change of the rotor/propeller aerodynamic interference along with the speed.

2) How to improve the confidence of the trimming result of the double-propeller propulsion compound high-speed helicopter.

Because the double-propeller propulsion compound high-speed helicopter lacks wind tunnel data and test flight data, the confidence of the flight mechanics model is affected. Therefore, simply using a mechanism model to solve the trim can result in limited precision of the trim obtained, and difficulty in further improving the confidence level. The CFD method is used as a calculation aerodynamic method with high fidelity and capable of considering aerodynamic interference, so that the defect that interference consideration in a mechanism model is insufficient can be overcome, but the time is too long when the trimming result is calculated by using the CFD method alone. Therefore, the aerodynamic and aerodynamic moments with high fidelity can be obtained by organically combining the CFD method, the advantages of fully considering interference and the advantages of quickly calculating the mechanism model to obtain the trim descending gradient of the double-propeller propulsion composite high-speed helicopter, and the aerodynamic and aerodynamic moments of the two methods are coupled to obtain the trim result with high confidence.

In order to achieve the above object, the present invention adopts the following technical scheme:

a rotor/propeller aerodynamic disturbance calculation method comprising the steps of:

s1: calculating aerodynamic force and aerodynamic moment of a rotor wing, a propeller by using a phyllotoxin theory and a uniform inflow model, forming a low-precision high-efficiency calculation model, calculating aerodynamic force and aerodynamic moment of a machine body by using an empirical formula method, and establishing a flight mechanics mechanism model of the double-propeller propulsion compound high-speed helicopter;

S2: calculating aerodynamic force and aerodynamic moment of a rotor wing, a propeller on the basis of a CFD momentum source model, wherein the momentum source model calculates aerodynamic force of a blade micro-segment by using flow field speed in the CFD model, and simultaneously calculates Jacobi matrix and descending gradient of rotor wing and propeller balancing by using a low-precision high-efficiency calculation model in S1; on the basis, a double-screw propulsion composite high-speed helicopter full-plane state aerodynamic force and aerodynamic moment CFD calculation model is established;

s3: calculating the manipulation quantity and attitude angle of a certain stable flight state of the flight mechanics mechanism model in the S1 by using a Newton iteration method;

s4: inputting the manipulation quantity and the attitude angle obtained in the step S3 into a CFD full-machine state aerodynamic force and aerodynamic moment calculation model, correcting aerodynamic force and aerodynamic moment in a low-precision high-efficiency calculation model by using aerodynamic force and aerodynamic moment of a momentum source model, calculating a descending gradient of balancing of the momentum source model, and continuously correcting manipulation until the rotor and the propeller reach target aerodynamic force and aerodynamic moment;

s5: calculating aerodynamic force and aerodynamic moment of the whole machine under the body shafting in the CFD model, judging whether the difference between the aerodynamic force and aerodynamic moment and the trimming target value meets a convergence condition, if so, obtaining a trimming result with high confidence coefficient, otherwise, performing S6;

S6: correcting aerodynamic force of the mechanism model according to the difference value obtained in the step S5, repeating balancing calculation, and returning to the step S4 until the difference value between the aerodynamic force and the balancing target value meets a convergence condition, so as to obtain a balancing result with high confidence coefficient;

s7: and respectively calculating aerodynamic forces of the isolated rotor, the isolated propeller and the rotor/propeller combination in a trimming state to obtain the aerodynamic disturbance quantity between the rotor/propellers along with the speed change.

Further, blade micro-end aerodynamic force is obtained through a phyllotoxin theory, and the formula is as follows:

wherein dF _A The aerodynamic force born by the blade micro-segment is ρ is air density, Ω is rotor rotation angular velocity, R is rotor radius, and α _∞ For the slope of the airfoil lift line, c is the chord length of the blade, μ _T For tangential velocity of blade profile, mu _P The normal speed of the blade profile is that theta is the attack angle of the blade micro-segment, and dr is the length element of the blade micro-segment;

the calculation formula of the uniform inflow model of the rotor wing is as follows:

wherein,uniform inflow speed of rotor, C _T The drag coefficient of the rotor, the dimensionless coefficient of the drag provided by the rotor, mu, the rotor forward ratio, the ratio of the tangential speed of the rotor profile to the speed of the rotor tip, lambda ₁ The inflow ratio of the rotor represents the ratio of the normal speed of the rotor profile to the tip speed of the rotor;

The uniform inflow model of the propeller also uses the model, and the force and the moment are calculated in a numerical integration mode; respectively segmenting a propeller disc in the circumferential direction and the radial direction, firstly summing in the radial direction to obtain aerodynamic force on the circumferential segmentation, and then summing in the circumferential direction to obtain aerodynamic force and aerodynamic moment of the propeller disc, wherein the segmentation number does not influence the calculation result of the aerodynamic force of the propeller, and the rotor wing model and the propeller model are low-precision high-efficiency calculation models;

other parts such as the machine body are non-rotating parts, and aerodynamic force and aerodynamic moment of the machine body are obtained by using an empirical formula method;

the double-propeller propulsion compound high-speed helicopter is regarded as a rigid body, and a rigid body six-degree-of-freedom motion equation is established:

u, v, w are the linear speeds of the helicopter along the x, y, z axes of the body coordinate system,resultant forces of the helicopter along the machine body coordinate systems x, y and z are respectively shown as p, q and r, angular speeds of the helicopter along the machine body coordinate systems x, y and z are respectively shown as g, gravitational acceleration, phi, theta and phi, and roll angle, pitch angle and yaw angle of the helicopter are respectively shown as g>Respectively the resultant moment of the helicopter along the machine body coordinate systems x, y and z.

Further, the CFD momentum source model calculates the attack angle of the blade micro-segment by the following calculation

Wherein alpha is the attack angle of the micro-segment of the blade, theta is the pitch of the blade root, and theta _tw V is the negative torque of the blade _n 、v _φ 、v _s The difference between the air flow speed at the blade micro-segment and the micro-segment rotation speed in the cylindrical coordinate system is respectively the axial speed, the circumferential speed and the radial speed,the speed of waving for the blade micro-segment;

the two-dimensional airfoil lift resistance coefficient corresponding to the attack angle of the blade micro-segment is obtained by a table lookup method, and the formula is as follows:

wherein L is the lift force of the blade micro-segment, D is the resistance of the blade micro-segment, ρ is the grid point fluid density, v is the grid fluid velocity of the blade micro-segment relative to the blade micro-segment, C _l For lift coefficient, C _d C is the blade chord length, dr is the blade micro-segment length; obtaining aerodynamic force on the blade micro-segment, converting the aerodynamic force into a hub coordinate system through coordinates, and adding the aerodynamic force in unit time serving as a source term into an N-S equation; and (3) calculating moment of the aerodynamic forces of all the micro sections on the center of the hub, and summing to obtain aerodynamic forces and aerodynamic moments of the rotor wing and the propeller.

Further, a low-precision high-efficiency calculation model based on the phyllin theory and the uniform inflow model is used for calculating the descending gradient of rotor and propeller balancing in the momentum source model, and the increment of the manipulation amount of the rotor and the propeller balancing is calculated by the following formula:

In θ ₀ For the total distance A ₁ For transverse period change of distance, B ₁ Is longitudinal periodic variable pitch, T is rotor pulling force, M _x 、M _y For the pneumatic rolling moment and the pneumatic pitching moment of the rotor, a subscript a represents the target aerodynamic force and aerodynamic moment, and a subscript i represents the aerodynamic force and aerodynamic moment obtained by the ith calculation; continuously correcting the operation of the rotor wing and the propeller in the momentum source model through the increment of the operation amount until the aerodynamic force and the aerodynamic moment of the rotor wing and the propeller in the momentum source model reach target values, and considering the rotor wing and the propeller to be in a balancing state;

to reduce the computational burden and ensure computational accuracy, the grid is encrypted near the fuselage and at the momentum source of the rotor propulsion propeller.

Further, rotor wing and propeller balancing under the full-aircraft state are carried out before aerodynamic force and aerodynamic moment of the helicopter are calculated in the CFD model, the following formula is a rotor wing balancing constraint equation, and only the first term is considered by the propeller;

T(θ ₀ ,A ₁ ,B ₁ )-T _a ＝0

M(θ ₀ ,A ₁ ,B ₁ )-M _a ＝0

L(θ ₀ ,A ₁ ,B ₁ )-L _a ＝0

in θ ₀ Representing the collective pitch, A ₁ Represents the transverse cyclic variation of the rotor wing, B ₁ Represents the longitudinal cyclic variation of the rotor, T (theta ₀ ,A ₁ ,B ₁ ) Representing the tension generated by the rotor, T being dependent on the collective, transverse cyclic and longitudinal cyclic factors _a Represents the target pneumatic tension, M (θ) ₀ ,A _1, B ₁ ) Representing the moment of roll aerodynamic produced by the rotor, M _a Represents the target roll aerodynamic moment, L (θ) ₀ ,A ₁ ,B ₁ ) Representing pitch aerodynamic moment produced by rotor, L _a Representing a target pitch aerodynamic moment;

correcting low-precision high-efficiency calculation model rotor wing, propeller aerodynamic force and aerodynamic moment through a momentum source model; obtaining the aerodynamic force of a rotor wing and a propeller of a coupled momentum source model, and the rotor wing balancing formula is as follows

Wherein T is ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Represents the pulling force of a rotor wing in a low-precision high-efficiency calculation model in the n+1th iteration, M ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the rolling aerodynamic moment of a rotor wing in a low-precision high-efficiency calculation model in n+1th iteration, L ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the pitching aerodynamic moment of the rotor wing in the low-precision high-efficiency calculation model in the n+1th iteration,representing the aerodynamic drag of the rotor calculated by the momentum source model in the nth iteration, +.>Representing the roll aerodynamic moment of the rotor calculated by the momentum source model in the nth iteration,/->Representing the pitch aerodynamic moment of the rotor calculated by the momentum source model in the nth iteration, T _a Representing the target pneumatic tension, M _a Representing target roll aerodynamic moment, L _a Representing a target pitch aerodynamic moment;

solving the equation to obtain the descending gradient of rotor and propeller trimming, and correcting the operation of the rotor and propeller in the momentum source model, so that the rotor and propeller in the state of the full-aircraft are trimmed in the CFD model, and then the full-aircraft trimming is performed.

Further, the double-propeller propulsion compound high-speed helicopter trim constraint equation used in the invention is as follows:

in the method, in the process of the invention,representing resultant force components in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing forces along the x, y and z axis directions of the machine body; />Representing resultant force components in the machine body coordinate system in the ith iteration obtained by the CFD model, and representing forces along the x, y and z axis directions of the machine body; />Representing resultant force components in the machine body coordinate system in the ith iteration of the mechanism model, and representing forces along the x, y and z axes of the machine body; />Representing a resultant moment component in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing moment around the x, y and z axis directions of the machine body; />Representing a resultant moment component in an engine body coordinate system in the ith iteration obtained by the CFD model, and representing moment around the x, y and z axis directions of the engine body; />And (3) representing the resultant moment components in the machine body coordinate system in the ith iteration of the mechanism model, and representing the moment around the x, y and z axes of the machine body.

Further, the specific steps of trimming are as follows:

1) Solving a balancing result through a mechanism model by using a Newton iteration method, wherein the result is an initial value of CFD model balancing calculation;

2) Inputting the gesture, manipulation, waving angle and front flying speed parameters obtained by balancing into a CFD model, and calculating aerodynamic force and aerodynamic moment with high confidence by using the CFD model;

3) The aerodynamic force and the aerodynamic moment of a rotor wing in the CFD momentum source model and the aerodynamic force and the aerodynamic moment of a propeller are corrected in a low-precision and high-efficiency mode, the increment of the operation amount is obtained through the low-precision and high-efficiency mode, the operation in the momentum source model is corrected until the rotor wing and the propeller are balanced, and the aerodynamic force and aerodynamic moment correction formula is as follows;

in the method, in the process of the invention,representing the aerodynamic forces or moments of the model rotor or propeller corrected in the n+1th iteration with low precision and high efficiency, +.>Representing aerodynamic force or moment of rotor or propeller calculated by low-precision high-efficiency calculation model in n+1th iteration, < ->Representing the aerodynamic force or moment of the rotor or propeller calculated by the momentum source model in the nth iteration, F/M _a Representation ofA target aerodynamic force or moment of the rotor or propeller;

4) Calculating aerodynamic resultant force and aerodynamic resultant moment of the whole machine in the CFD model after balancing the rotor wing and the propeller, correcting the aerodynamic resultant force and aerodynamic resultant moment in the flight mechanics model by using the aerodynamic resultant force and the aerodynamic resultant moment, and calculating to obtain new manipulation quantity and attitude angle through the flight mechanics model, wherein a aerodynamic force and aerodynamic moment correction formula is as follows;

In the method, in the process of the invention,representing the modified mechanism model aerodynamic force or aerodynamic moment in the n+1th iteration;representing aerodynamic forces or moments calculated by the mechanism model in the n+1th iteration; />Representing aerodynamic forces or moments calculated by the CFD model in the nth iteration; />Representing aerodynamic forces or moments calculated by the mechanism model in the nth iteration;

5) Obtained by judgmentWhether the convergence condition is satisfied; if yes, finishing balancing to obtain balancing gesture and operation; if not, returning to the step 2) for re-calculation until the convergence condition is met.

Compared with the prior art, the invention has the advantages that:

1. compared with the method for directly calculating the balancing Jacobi matrix or directly searching the balancing result in the CFD model, the method has the advantages of less calculation times and shorter calculation time. According to the invention, the trimming result can be obtained by only 2-3 times of interaction of the data between the CFD model and the mechanism model, and the method has engineering practical value.

2. The invention can obtain trimming data with higher confidence, considers the influence of interference along with speed and operation change, and compared with a wind tunnel test, the trimming result obtained by the invention is closer to the operation amount in the wind tunnel test than the trimming result obtained by calculation of a mechanism model. Therefore, the method can provide interference factor reference data for high-confidence modeling of the double-screw propulsion compound high-speed helicopter, and provides a basis for accurately researching the flight quality and the flight performance of the helicopter.

3. The interference calculation method is also suitable for other rotor craft in theory, especially for rotor craft with complex aerodynamic interference, limited wind tunnel test data and test flight data, which makes it difficult to build high confidence mechanism model, and the difference is only that the interference between different components is selected when calculating the aerodynamic interference.

Drawings

FIG. 1 is a flow chart of a rotor aerodynamic model calculation in accordance with an embodiment of the present invention;

FIG. 2 is a diagram of a dual-rotor propulsion compound high-speed helicopter face grid and a momentum source according to an embodiment of the invention; wherein 1 is a machine body surface grid, 2 is a rotor wing momentum source, 3 is a right propeller momentum source, and 4 is a left propeller momentum source.

FIG. 3 is a flow chart of a balancing method according to an embodiment of the present invention;

FIG. 4 is a diagram of a double-propeller propulsion composite high-speed helicopter wind tunnel test apparatus according to an embodiment of the invention; wherein 5 is a wind tunnel, 6 is a six-component balance, and 7 is a double-propeller propulsion compound high-speed helicopter.

FIG. 5 is a comparative chart of trim amounts for an embodiment of the present invention; (a) rotor collective pitch, (b) longitudinal cyclic pitch, (c) transverse cyclic pitch, (d) differential pitch, (e) average pitch;

FIG. 6 is a schematic view of a rotor/propeller combination according to an embodiment of the present invention; wherein 8 is the rotor, 9 right screw, 10 is left screw.

FIG. 7 is a graph showing rotor tension as a function of speed for an embodiment of the present invention;

FIG. 8 is a graph showing the variation of propeller tension with speed according to an embodiment of the present invention; wherein (a) is a left propeller and (b) is a right propeller.

FIG. 9 is a graph of rotor/propeller disturbance speed clouds at different speeds in accordance with an embodiment of the present invention; wherein (a) is 5m/s and (b) is 20m/s.

FIG. 10 is a cross-sectional velocity cloud of a right propeller of example 5m/s of the present invention; wherein (a) is an isolated right propeller and (b) is a rotor-right propeller.

FIG. 11 is a graph showing rotor tension as a function of speed for an embodiment of the present invention;

FIG. 12 is a graph showing the variation of propeller tension with speed according to an embodiment of the present invention; wherein (a) is a left propeller and (b) is a right propeller;

FIG. 13 is a longitudinal section flow diagram of the fuselage in the state of a full machine of 20m/s in accordance with an embodiment of the present invention;

FIG. 14 is a graph showing a cloud of speed around a right propeller in a full-engine state according to example 5m/s of the present invention.

Detailed Description

The invention will be described in further detail below with reference to the accompanying drawings and by way of examples in order to make the objects, technical solutions and advantages of the invention more apparent.

The first step, calculating aerodynamic force and aerodynamic moment of a rotor wing, a propeller by using a phyllin theory and a uniform inflow model, forming a low-precision high-efficiency calculation model, calculating aerodynamic force and aerodynamic moment of a machine body by using an empirical formula method, and establishing a flight mechanics mechanism model of the double-propeller propulsion compound high-speed helicopter.

And secondly, calculating aerodynamic force and aerodynamic moment of the rotor wing, the propeller on the basis of a CFD momentum source model, wherein the momentum source model uses flow field speed in the CFD model to calculate aerodynamic force of the blade micro-segment, and simultaneously uses a low-precision high-efficiency calculation model in the first step to calculate Jacobi matrix and descent gradient of rotor wing and propeller balancing. On the basis, a double-screw propulsion composite high-speed helicopter full-plane state aerodynamic force and aerodynamic moment CFD calculation model is established.

And thirdly, calculating the manipulation quantity and attitude angle of a certain stable flight state of the mechanism model in the first step by using a Newton iteration method.

And fourthly, inputting the calculated trim state operation and gesture into a CFD full-machine state aerodynamic force and aerodynamic moment calculation model. Because the rotor and the propeller are subject to complex aerodynamic disturbances, the rotor and the propeller components in the CFD model may have rotor, propeller un-trims for the steering and aerodynamic forces given by the mechanism model. In order to balance the rotor and the propeller, the aerodynamic force and the aerodynamic force moment of the rotor and the propeller in the momentum source model are used for correcting the aerodynamic force and the aerodynamic force moment of the rotor and the propeller in the low-precision efficient calculation model, the descending gradient of the balance of the rotor and the propeller in the momentum source model is calculated, and the operation is continuously corrected until the rotor and the propeller reach the target aerodynamic force moment and the target aerodynamic force moment.

And fifthly, calculating aerodynamic force and aerodynamic moment of the whole machine under the body axis in the CFD model, judging whether the difference between the aerodynamic force and aerodynamic moment and the trimming target value meets a convergence condition, if so, obtaining a trimming result with high confidence, otherwise, performing a sixth step.

And sixthly, taking the difference between aerodynamic force and aerodynamic moment obtained by the CFD model in the fifth step and the target value as aerodynamic force of the aerodynamic force increment correction mechanism model caused by aerodynamic interference of each component, and completing new trim calculation to obtain new trim state operation and posture. Repeating the fourth step and the fifth step until the difference between the aerodynamic force and aerodynamic moment of the helicopter and the trimming target value meets the convergence condition in the fifth step, and obtaining a trimming result with high confidence.

And seventhly, respectively calculating aerodynamic forces of the isolated rotor, the isolated propeller and the rotor/propeller combination under the trim state obtained in the step to obtain the aerodynamic disturbance quantity between the rotor/propellers along with the speed change.

1. Combined high-speed helicopter mechanism modeling

In the mechanism modeling process of the double-propeller propulsion composite high-speed helicopter, rotor modeling is the most complex and key, and the core is to establish interaction among a two-dimensional airfoil aerodynamic model, a blade motion model and an inflow model, as shown in fig. 1. The rotor blade motion comprises rotation, first-order waving and forward-flying motion along with a helicopter, and blade micro-end aerodynamic force is obtained through a phyllin theory:

Wherein dF _A The aerodynamic force born by the blade micro-segment is ρ is air density, Ω is rotor rotation angular velocity, R is rotor radius, and α _∞ For the slope of the airfoil lift line, c is the chord length of the blade, μ _T For tangential velocity of blade profile, mu _P The normal speed of the blade profile is theta, the attack angle of the blade micro-segment and dr, the length element of the blade micro-segment.

The rotor inflow model is an even inflow model, the model is simple to realize, and the calculation formula is as follows:

wherein,uniform inflow speed of rotor, C _T The drag coefficient of the rotor, the dimensionless coefficient of the drag provided by the rotor, mu, the rotor forward ratio, the ratio of the tangential speed of the rotor profile to the speed of the rotor tip, lambda ₁ The inflow ratio of the rotor represents the ratio of the rotor profile normal speed to the rotor tip speed.

The propeller also uses the model, but because the radius of the propeller on the left side and the right side is smaller and the flapping is not considered, some assumptions made during rotor modeling are not applicable any more, and the aerodynamic formula of the propeller cannot be obtained in an analytic mode, the force and the moment are calculated in a numerical integration mode. The propeller disc is segmented in the circumferential direction and the radial direction respectively, aerodynamic force on the circumferential segments is obtained by summing in the radial direction, aerodynamic force and aerodynamic moment of the propeller disc are obtained by summing in the circumferential direction, and the number of segments does not affect the calculation result of the aerodynamic force of the propeller. The rotor wing model and the propeller model are low-precision and high-efficiency calculation models.

Other parts such as the machine body are non-rotating parts, and aerodynamic force and aerodynamic moment of the machine body are obtained by using an empirical formula method.

2. CFD aerodynamic model of composite high-speed helicopter

The invention uses a Starcm+ solver to calculate and solve N-S equation of a conservation format by a finite volume method, and the control equation is that

Wherein W is a flow field conservation variable, F _c To convection flux, F _v Is viscous flux, Q is the source term, t is time, Ω is the volume of the control volume,for the area of the control body, dS is the infinitesimal area of the control body.

The turbulence model uses a k-omega SST model with higher near wall surface precision in a Reynolds average stress model, and the model has larger calculation amount, but the accuracy degree of the model is verified for a plurality of times. To reduce the effect of the calculated field wall, the distance from the flow field wall to the fuselage is ten times the length of the fuselage features.

The main part of the aerodynamic force simulation of the helicopter is the simulation of the aerodynamic force of a rotor wing and a propeller, and the common CFD rotor wing and propeller aerodynamic force simulation method comprises a body-attached grid method, a momentum source method and the like. Although the body-attached grid method has higher accuracy, the required grid number is larger, and the calculation time cost is too high. The main idea of the steady momentum source method is to convert the periodic unsteady action of the blade on the air into a quasi-steady flow through a time-averaged integral method, and neglect the surface details of the blade disc, so that steady calculation can be used, and the calculation resources are saved. The momentum source is selected to replace the paddle disc, so that the calculation aerodynamic force is guaranteed to have higher fidelity, and the calculation efficiency is improved. The momentum source model calculates the aerodynamic force of the blade micro-segment by calculating the attack angle by utilizing the CFD flow field speed and using the phyllin theory.

The momentum source model calculates the attack angle of the blade micro-segment through the method (4)

Wherein alpha is the attack angle of the micro-segment of the blade, theta is the pitch of the blade root, and theta _tw V is the negative torque of the blade _n 、v _φ 、v _s The difference between the air flow speed at the blade micro-segment and the micro-segment rotation speed in the cylindrical coordinate system is respectively the axial speed, the circumferential speed and the radial speed,the speed of the blade micro-segment is the waving speed. The corresponding two-dimensional airfoil rise resistance coefficient under the attack angle is obtained by a table lookup method through

Wherein L is the lift force of the blade micro-segment, D is the resistance of the blade micro-segment, ρ is the grid point fluid density, v is the grid fluid velocity of the blade micro-segment relative to the blade micro-segment, C _l For lift coefficient, C _d And c is the blade chord length, dr is the blade micro-segment length. And obtaining aerodynamic force on the blade micro-segment, converting the aerodynamic force into a hub coordinate system through coordinates, and adding the aerodynamic force in unit time serving as a source term into an N-S equation. And (3) calculating moment of the aerodynamic forces of all the micro sections on the center of the hub, and summing to obtain aerodynamic forces and aerodynamic moments of the rotor wing and the propeller.

The invention uses a low-precision high-efficiency calculation model to calculate the descending gradient of rotor and propeller balancing in a momentum source model, and calculates the increment of the operation amount of rotor and propeller balancing through a step (6), wherein, the propeller does not flap and has a transverse and longitudinal period variable pitch, so that only the descending gradient of the rotor and the propeller balancing is calculatedAn item.

In θ ₀ For the total distance A ₁ For transverse period change of distance, B ₁ For longitudinal period variation, TFor rotor tension, M _x 、M _y For rotor aerodynamic roll moment and aerodynamic pitch moment, subscript a represents target aerodynamic and aerodynamic moment and subscript i represents aerodynamic and aerodynamic moment calculated the ith time. The rotor and the propeller in the momentum source model are continuously modified through the increment of the manipulation amount until the aerodynamic moment and the aerodynamic moment of the rotor and the propeller reach the target values, and the rotor and the propeller are considered to be in a trimming state.

To reduce the computational burden and ensure computational accuracy, the grid is encrypted near the fuselage and at the momentum source of the rotor propulsion propeller. The computational model has been validated for grid independence, details of which are shown in FIG. 2.

3. Trimming method

During stable flight of the double-propeller propulsion compound high-speed helicopter, the dynamic equation is that

Wherein x= [ u v w p q r ]] ^T Because the double-propeller propulsion compound high-speed helicopter has five steering amounts, steering redundancy exists, and the problem is solved by determining the pitch angle in trim calculation. Balancing based on the model is the main stream method for balancing of the helicopter at present ^[10] . However, the aerodynamic interference of each component of the double-propeller propulsion compound high-speed helicopter is serious, and a large amount of wind tunnel test data and test flight data are lacked, so that the aerodynamic force calculation confidence coefficient of each component is limited in mechanism modeling, and the confidence coefficient of the trimming result is difficult to further improve.

The balancing method provided by the invention organically combines a double-propeller propulsion compound high-speed helicopter mechanism model with a traditional CFD method. The method comprises the core thought of firstly coupling a rotor wing and a propeller in a low-precision high-efficiency rapid calculation model balancing CFD model, and then using the CFD model with higher fidelity to calculate aerodynamic force and aerodynamic moment of a mechanism model with lower fidelity to correct the aerodynamic force and aerodynamic moment.

Because the rotor/propeller aerodynamic interference of the double-propeller propulsion composite high-speed helicopter is complex, the rotor and the propeller are in an untrimmed state when calculated by using the trimming method, so that the data are needed to be interacted for a plurality of times, the total calculation time is long, the rotor and the propeller trimming in a full-aircraft state is performed before the aerodynamic force and the aerodynamic moment of the helicopter are calculated in a CFD model, the formula (14) is a rotor trimming constraint equation, and the propeller only considers the first term.

In θ ₀ Representing the collective pitch, A ₁ Represents the transverse cyclic variation of the rotor wing, B ₁ Represents the longitudinal cyclic variation of the rotor, T (theta ₀ ,A ₁ ,B ₁ ) Representing the tension generated by the rotor, T being dependent on the collective, transverse cyclic and longitudinal cyclic factors _a Represents the target pneumatic tension, M (θ) ₀ ,A ₁ ,B ₁ ) Representing the moment of roll aerodynamic produced by the rotor, M _a Represents the target rolling pneumatic tension, L (theta) ₀ ,A ₁ ,B ₁ ) Representing pitch aerodynamic moment produced by rotor, L _a Indicating the target pitch aerodynamic drag.

Correcting the low-precision high-efficiency calculation model rotor wing and propeller aerodynamic force through the momentum source model to obtain the rotor wing and propeller aerodynamic force of the coupling momentum source model, wherein the rotor wing trimming formula is as follows

Wherein T is ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Represents the pulling force of a rotor wing in a low-precision high-efficiency calculation model in the n+1th iteration, M ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the rolling aerodynamic moment of a rotor wing in a low-precision high-efficiency calculation model in n+1th iteration, L ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the pitching aerodynamic moment of the rotor wing in the low-precision high-efficiency calculation model in the n+1th iteration,representing the aerodynamic tension calculated by the momentum source model in the nth iteration, < >>Representing the roll aerodynamic moment of the rotor calculated by the momentum source model in the nth iteration,/->The pitch aerodynamic moment of the rotor wing calculated by the momentum source model in the nth iteration is represented, ta represents the target aerodynamic tension, ma represents the target roll aerodynamic moment, and La represents the target pitch aerodynamic moment. Solving the equation to obtain the descending gradient of rotor and propeller balancing in the momentum source, and correcting the operation of the rotor and the propeller, so that the rotor and the propeller in the state of the full-aircraft are firstly balanced in the CFD model, and then the full-aircraft balancing is carried out.

The aerodynamic and aerodynamic moments in the modified mechanism model are the sum of the aerodynamic and aerodynamic moments in the original mechanism model and the difference between the CFD model and the mechanism model aerodynamic and aerodynamic moments in the previous iteration step, and then the helicopter trim constraint equation is

/>

Wherein, in the formula, the chemical formula,representing resultant force components in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing forces along the x, y and z axis directions of the machine body; / >Representing resultant force components in the machine body coordinate system in the ith iteration obtained by CFD simulation, and representing forces along the x, y and z axis directions of the machine body; />Representing resultant force components in the machine body coordinate system in the ith iteration of the mechanism model, and representing forces along the x, y and z axes of the machine body; />Representing a resultant moment component in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing moment around the x, y and z axis directions of the machine body;representing the resultant moment components in the coordinate system of the machine body in the ith iteration obtained by CFD simulation, and representing the moment about the x, y and z axes of the machine body, < + >>And (3) representing the resultant moment components in the machine body coordinate system in the ith iteration of the mechanism model, and representing the moment around the x, y and z axes of the machine body. Solving the equation by Newton iteration to obtain the trimming state in the mechanism model, and changing the attitude angle and operation of the CFD model until the aerodynamic and aerodynamic moments and the target valueThe difference is smaller than the residual error, so that a trimming result with higher confidence is obtained.

The method can effectively reduce the data interaction times between the CFD model and the mechanism model when the double-propeller propulsion compound high-speed helicopter is configured, thereby reducing the calculation time and ensuring the engineering practicability. The specific steps of trimming are as follows:

1. Solving a balancing result through a mechanism model by using a Newton iteration method, wherein the value is an initial value of CFD model balancing calculation;

2. inputting parameters such as the gesture, the manipulation, the waving angle and the forward flying speed obtained by balancing into a CFD model, and calculating aerodynamic force and aerodynamic moment with high confidence coefficient by using the model;

3. the aerodynamic force and the aerodynamic moment in the aerodynamic model are calculated efficiently with low precision by using the rotor aerodynamic force and the aerodynamic moment of the CFD momentum source model and the aerodynamic force and the aerodynamic moment of the propeller are corrected, the increment of the operation amount is obtained by using the low precision efficient calculation model, the operation in the momentum source model is corrected until the rotor and the propeller are balanced, and the aerodynamic force and the aerodynamic moment are corrected according to the following formula;

in the method, in the process of the invention,representing the aerodynamic forces or moments of the model rotor or propeller corrected in the n+1th iteration with low precision and high efficiency, +.>Representing aerodynamic force or moment of rotor or propeller calculated by low-precision high-efficiency calculation model in n+1th iteration, < ->Representing the aerodynamic force or moment of the rotor or propeller calculated by the momentum source model in the nth iteration, F/M _a Indicating the purpose of the rotor or propellerA aerodynamic force or moment.

4. After the rotor wing and the propeller are trimmed, calculating the aerodynamic resultant force and aerodynamic resultant moment of the whole machine in the CFD model, correcting the aerodynamic resultant force and aerodynamic resultant moment in the flight mechanics model by using the aerodynamic resultant force and the aerodynamic resultant moment, and calculating to obtain a new manipulation quantity and attitude angle by the flight mechanics model, wherein a aerodynamic force and aerodynamic moment correction formula is as follows;

In the method, in the process of the invention,representing the modified mechanism model aerodynamic forces or moments in the n+1 iteration. />Representing the aerodynamic force or moment calculated by the mechanism model in the n+1 iteration. />Representing the aerodynamic forces or moments calculated by the CFD model in the nth iteration. />Representing the aerodynamic force or moment calculated by the mechanism model in the nth iteration.

5. The result of judgment 4Whether the convergence condition is satisfied. If yes, finishing balancing to obtain balancing gesture and operation; if not, returning to the step 2 to perform calculation again until the convergence condition is met.

The specific balancing flow is shown in fig. 3.

4. Wind tunnel test verification of balancing method

In order to verify that the balancing calculation method has certain accuracy, the balancing result, the mechanism model balancing result and the wind tunnel test result are used for comparison. The wind tunnel test is completed in a national-level key laboratory of rotor dynamics of the university of aviation aerospace in Nanjing, the test purpose is to find the balancing control amount of the double-propeller propulsion compound high-speed helicopter in the wind tunnel at the speed of 0-20m/s, and the test bed device is shown in fig. 4.

And solving a balancing equation in the mechanism model and the balancing calculation method, and respectively obtaining a set of mechanism model balancing values and balancing method calculation values. The test results, the mechanism model trim values, and the trim method calculations are compared as shown in fig. 5. For clarity, the figures are labeled with calculated values for the balancing method based on CFD model balancing values.

As can be seen from FIG. 5, the trim result obtained by the trim calculation method is closer to the test value than the trim result of the mechanism model, indicating that the method has higher accuracy.

5. Rotor/propeller aerodynamic disturbance analysis

The rotor and the propeller are rotating parts of the helicopter, the aerodynamic characteristics of the rotor and the propeller are complex, the flow mechanism is more variable when the rotor and the propeller are disturbed, and the type of disturbance is divided into hovering and forward flying.

5.1 hover aerodynamic disturbance analysis

And (3) calculating and comparing the rotor/propeller combination under the balancing operation when hovering, and comparing the rotor tension of the isolated rotor with the rotor tension of the isolated propeller. The rotor/propeller combination is shown in fig. 6, and the tension pair ratio is shown in table 1

Table 1 rotor/propeller drag comparison

As can be seen from table 1, the rotor aerodynamic changes are small in the hover state, indicating that the rotor is not substantially disturbed by the propeller in hover.

Under the interference of the rotor downwash, the efficiency of the left and right propellers is increased, because the propellers are directly positioned in the rotor downwash, and the dynamic pressure near the propeller disc is increased, so that the efficiency of the propellers is increased.

5.2 front flight aerodynamic disturbance analysis

The rotor/propeller combination, the isolated rotor and the rotor of the isolated propeller under the trim state manipulation at different forward speeds are calculated and compared, and the propeller tension changes are shown in fig. 7 and 8.

As can be seen from fig. 8, the effect of the propeller on the rotor is small at each speed, indicating that the propeller is not the main cause of aerodynamic changes in the rotor.

The effect of rotor downwash on the propeller is greater in this speed segment and the propeller drag of the left propeller under rotor disturbances increases. While the right propeller is disturbed to present different results, except that the forward flight speed is about 5 m/s. Before 15m/s, the pitch of the right propeller is positive and smaller, the influence of the circumferential airflow of the left-handed rotor is larger, the inflow ratio of the right propeller is reduced, and the pulling force is reduced; after 15m/s, the right propeller pitch is larger and the circumferential airflow effect is smaller, and the interference at this time has the same trend as that of the left propeller. Except that the forward flight speed of the right propeller is 5m/s, the absolute value of aerodynamic force change caused by the interference does not obviously change along with the increase of speed in the speed section. As shown in fig. 9, the rotor interference with the propeller is always present in this speed segment.

Notably, a significant reduction in the pull of the isolated right propeller occurs at a forward speed of 5m/s, with substantially no pull. By looking at the speed cloud chart 10 (a), the induced speed of the propeller at the speed is basically 0, and the edge of the propeller disc is free from the tip vortex caused by the pressure difference between the upper surface and the lower surface, so that the right propeller can be considered to enter the vortex ring state. As shown in speed cloud 10 (b), in the combined rotor/propeller state, the rotor downwash at this speed still severely interferes with the right propeller, which disturbances make the right propeller somewhat free of the vortex ring effect, increasing the efficiency of the right propeller.

6. Analysis of the influence of the body on the aerodynamic disturbance of a rotor/propeller

In order to consider the influence of other components on the interference characteristics of the rotor/propeller, the aerodynamic force of the engine body-rotor/propeller combination and the aerodynamic force of the rotor/propeller combination under the trim operation are calculated and compared, the engine body in the invention particularly refers to an engine body, wings and a flat-drooping tail piece, and the engine body-rotor/propeller combination is in a full-engine state, so that the type of interference is divided into two types of hovering and forward flying.

6.1 hover aerodynamic disturbance analysis

Calculating and comparing the state of the whole machine under the balancing operation and the tension of the rotor and the propeller of the rotor/propeller combination when hovering, as shown in Table 2

Table 2 rotor/propeller drag comparison

As can be seen from Table 2, the tension of the rotor in the full-aircraft state is obviously increased, which means that the rotor in hovering is acted by the ground effect generated by the engine body parts ^[11] The action improves the tension efficiency of the rotor wing by about 5%.

Under the interference of the rotor downwash, the efficiency of the left and right propellers is increased, but the increase amplitude is smaller than that of the rotor/propeller combination in the whole machine state. The change value of the attack angle caused by the downward washing air flow is smaller under the state of the whole machine due to the blocking effect of the nacelle and the wing on the downward washing air flow of the rotor wing no matter the left propeller or the right propeller.

6.2 front flight aerodynamic disturbance analysis

The rotor, propeller pull changes for the full machine state and rotor/propeller combination under the trim state maneuver described above are calculated versus at different speeds, as shown in fig. 11 and 12.

As can be seen from fig. 11, the rotor tension in the full-aircraft state shows a tendency to increase and decrease in comparison to the rotor/propeller combination, indicating that the body components have an effect on the rotor during forward flight.

At small speeds, the ground effect produced by the body has not completely disappeared, resulting in a slight increase in rotor aerodynamic forces; with increasing speed, the above-mentioned ground effect disappears, and the air flow is affected by the machine body, resulting in interference of the aerodynamic force of the rotor. As can be seen from fig. 13, the air flow is caused to flow upwards when flowing through the handpiece, reducing the axial air flow at the paddle; when the air flows through the upper surface of the machine body, the air flows downwards, and the axial air flow at the paddle disc is increased. The asymmetry in rotor front and rear axial velocity is significantly enhanced, resulting in reduced rotor aerodynamic performance.

In this speed range, the propeller aerodynamic force of the propeller in the all-plane state and the rotor/propeller combination is very small except that the forward flight speed of the right propeller is about 5m/s, and the main factor that the propeller is disturbed when the downwash of the rotor is still in this speed range is considered. At 5m/s, however, aerodynamic forces are relatively reduced due to the limited ability of the nacelle's choke to attenuate right rotor vortex phenomena.

The above-described method according to the present invention may be implemented in hardware, firmware, or as software or computer code storable in a recording medium such as a CD ROM, RAM, floppy disk, hard disk, or magneto-optical disk, or as computer code originally stored in a remote recording medium or a non-transitory machine-readable medium and to be stored in a local recording medium downloaded through a network, so that the method described herein may be stored on such software process on a recording medium using a general purpose computer, special purpose processor, or programmable or special purpose hardware such as an ASIC or FPGA. It is understood that a computer, processor, microprocessor controller, or programmable hardware includes a memory component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code that, when accessed and executed by the computer, processor, or hardware, implements one rotor/propeller aerodynamic disturbance calculation method described herein. Further, when the general-purpose computer accesses code for implementing the processes shown herein, execution of the code converts the general-purpose computer into a special-purpose computer for executing the processes shown herein.

Those of ordinary skill in the art will appreciate that the embodiments described herein are intended to aid the reader in understanding the practice of the invention and that the scope of the invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific modifications and combinations from the teachings of the present disclosure without departing from the spirit thereof, and such modifications and combinations remain within the scope of the present disclosure.

Claims

1. A rotor/propeller aerodynamic disturbance calculation method, comprising the steps of:

2. A rotor/propeller aerodynamic disturbance calculation method according to claim 1, characterized in that: blade micro-end aerodynamic force is obtained through a phyllin theory, and the formula is as follows:

3. A rotor/propeller aerodynamic disturbance calculation method according to claim 1, characterized in that: the CFD momentum source model obtains the attack angle of the blade micro-segment through the following calculation

4. A rotor/propeller aerodynamic disturbance calculation method according to claim 2, characterized in that: calculating the descending gradient of rotor and propeller balancing in a momentum source model by using a low-precision high-efficiency calculation model based on a phyllin theory and a uniform inflow model, and calculating the increment of the manipulation amount of the rotor and propeller balancing by the following formula:

5. A rotor/propeller aerodynamic disturbance calculation method according to claim 1, characterized in that: rotor wing and propeller balancing under the full-aircraft state are carried out before aerodynamic force and aerodynamic moment of the helicopter are calculated in the CFD model, the following formula is a rotor wing balancing constraint equation, and only the first term is considered by the propeller;

T(θ ₀ ，A ₁ ，B ₁ )-T _a ＝0

M(θ ₀ ，A ₁ ，B ₁ )-M _a ＝0

L(θ ₀ ，A ₁ ，B ₁ )-L _a ＝0

in θ ₀ Representing the collective pitch, A ₁ Represents the transverse cyclic variation of the rotor wing, B ₁ Represents the longitudinal cyclic variation of the rotor, T (theta ₀ ,A ₁ ,B ₁ ) Representing the tension produced by the rotor, depending on collective, cyclic variation in transverse direction and circumferential in longitudinal directionPeriod variable pitch and other factors, T _a Represents the target pneumatic tension, M (θ) ₀ ,A ₁ ,B ₁ ) Representing the moment of roll aerodynamic produced by the rotor, M _a Represents the target roll aerodynamic moment, L (θ) ₀ ,A ₁ ,B ₁ ) Representing pitch aerodynamic moment produced by rotor, L _a Representing a target pitch aerodynamic moment;

Wherein T is ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Represents the pulling force of a rotor wing in a low-precision high-efficiency calculation model in the n+1th iteration, M ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the rolling aerodynamic moment of a rotor wing in a low-precision high-efficiency calculation model in n+1th iteration, L ⁿ⁺¹ (θ ₀ ,A ₁ ,B ₁ ) Representing the pitching aerodynamic moment of the rotor wing in the low-precision high-efficiency calculation model in the n+1th iteration,representing the aerodynamic drag of the rotor calculated by the momentum source model in the nth iteration, +.>Representing the passage of momentum source model in the nth iterationCalculated roll aerodynamic moment of the rotor,/->Representing the pitch aerodynamic moment of the rotor calculated by the momentum source model in the nth iteration, T _a Representing the target pneumatic tension, M _a Representing target roll aerodynamic moment, L _a Representing a target pitch aerodynamic moment;

6. A rotor/propeller aerodynamic disturbance calculation method according to claim 1, characterized in that: the trimming constraint equation of the double-propeller propulsion compound type high-speed helicopter used in the invention is as follows:

in the method, in the process of the invention,representing resultant force components in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing forces along the x, y and z axis directions of the machine body; / >Representing resultant force components in the machine body coordinate system in the ith iteration obtained by the CFD model, and representing forces along the x, y and z axis directions of the machine body; />Representing resultant force components in the machine body coordinate system in the ith iteration of the mechanism model, and representing forces along the x, y and z axes of the machine body; />Representing a resultant moment component in the machine body coordinate system in the i+1 step iteration of the mechanism model, and representing moment around the x, y and z axis directions of the machine body;representing a resultant moment component in an engine body coordinate system in the ith iteration obtained by the CFD model, and representing moment around the x, y and z axis directions of the engine body; />And (3) representing the resultant moment components in the machine body coordinate system in the ith iteration of the mechanism model, and representing the moment around the x, y and z axes of the machine body.

7. A rotor/propeller aerodynamic disturbance calculation method according to claim 1, characterized in that: the trimming method comprises the following specific steps:

In the method, in the process of the invention,representing the aerodynamic forces or moments of the model rotor or propeller corrected in the n+1th iteration with low precision and high efficiency, +.>Representing aerodynamic force or moment of rotor or propeller calculated by low-precision high-efficiency calculation model in n+1th iteration, < ->Representing the aerodynamic force or moment of the rotor or propeller calculated by the momentum source model in the nth iteration, F/M _a Representing a target aerodynamic force or moment of the rotor or propeller;