Method and device for determining take-off field length for single engine failure of a transport aircraft

Abstract

The application belongs to the technical field of take-off field performance design, and particularly relates to a method and device for determining the length of a take-off field of a transport aircraft with single-engine failure, and is applied to a lower-surface air-blowing flap powered lift transport aircraft. The method comprises the following steps: S1, determining the lift state take-off thrust of the transport aircraft with single-engine failure; S2, determining the acceleration and the path angle of the transport aircraft in the process of constant speed climbing according to the lift state take-off thrust; and S3, calculating the length of the take-off field of the transport aircraft with single-engine failure according to an integral formula. The application accurately describes the changes of the thrust, lift, drag and speed of the air-blowing flap powered lift transport aircraft with single-engine failure in the process of take-off, and can quickly and accurately calculate the length of the take-off field of the lower-surface air-blowing flap powered lift transport aircraft with single-engine failure.

Description

Technical Field

[0001] The present application belongs to the technical field of takeoff field performance design, and in particular relates to a method and device for determining the length of a takeoff field for a transport aircraft with a single engine failure. Background Art

[0002] The aerodynamic forces of a powered lift aircraft with blown flaps during takeoff are significantly affected by the power source, and engine failure also generates rolling and yaw moments. The dynamic models used to calculate takeoff field length for conventional aircraft are not applicable to powered lift aircraft with blown flaps. Summary of the Invention

[0003] In order to solve the above problems, the present application provides a method and device for determining the takeoff field length of a transport aircraft with a single engine failure, providing technical support for determining the takeoff field length of a transport aircraft with a single engine failure using a blown flap power lift system.

[0004] In a first aspect, the present application provides a method for determining the takeoff field length of a transport aircraft with a single engine failure, which is applied to a powered high-lift transport aircraft with blown flaps on the lower surface. The method comprises:

[0005] Step S1: Determine the takeoff thrust P of a transport aircraft in a lift-up state with a single engine failure. xzon ;

[0006] Step S2: Take-off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb;

[0007] Step S3: Calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula:

[0008]

[0009] Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, L R2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

[0010] Preferably, in step S1, the takeoff thrust P in the increased lift state is determined by the following formula: xzon :

[0011]

[0012] Among them, ne is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

[0013] Preferably, step S2 further comprises:

[0014] Step S21: Determine the takeoff lift coefficient C in the increased lift state L ;

[0015] Step S22: Determine the takeoff drag coefficient C in the increased lift state D ;

[0016] Step S23: Determine the acceleration a of the transport aircraft using the following formula:

[0017]

[0018] Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift;

[0019] Step S24: Determine the track angle θ of the constant speed climb using the following formula:

[0020]

[0021] Preferably, in step S21, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L :

[0022]

[0023] Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap, C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

[0024] Preferably, step S22 further includes:

[0025] Step S221: Determine the drag coefficient C generated by the rolling moment trim due to a single engine failure. Da ;

[0026] Step S222: Determine the drag coefficient C generated by the single engine failure pitching moment trim De ;

[0027] Step S223: Determine the drag coefficient C generated by the yaw moment trim due to single engine failure. Dr ;

[0028] Step S224: Calculate the trim resistance coefficient ΔC based on the following formula: D :

[0029]

[0030] Step S225: Calculate the takeoff drag coefficient C based on the following formula: D :

[0031]

[0032] Among them, C Doff is the drag coefficient in the non-powered lift state, C Db It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

[0033] Preferably, in step S221, the drag coefficient C generated by the single engine failure rolling moment trim is determined according to the following formula: Da :

[0034]

[0035] Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, C lδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

[0036] Preferably, step S222 further includes:

[0037] Step S2221: Determine the pitch moment coefficient increment C generated by the jet vector effect mp ;

[0038] Step S2222: Determine the pitching moment coefficient increment C generated by the jet flap flow. mb ;

[0039] Step S2223: Determine the pitch moment coefficient C for the missed approach climb using the following formula: m :

[0040] C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state;

[0041] Step S2224: Determine the drag coefficient C generated by the single engine failure pitching moment trim using the following formula: De :

[0042] C De =C Dδe δ e ;

[0043]

[0044] Among them, δ e Elevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

[0045] Preferably, in step S2221, the pitch moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp :

[0046]

[0047] Among them, C T is the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

[0048] Preferably, in step S2222, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb :

[0049]

[0050] Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

[0051] Preferably, in step S223, the drag coefficient C generated by the yaw moment trim due to single engine failure is determined according to the following formula: Dr :

[0052]

[0053] Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

[0054] A second aspect of the present application provides a device for determining the takeoff field length of a transport aircraft with a single engine failure, which is applied to a powered high-lift transport aircraft with blown flaps on the lower surface. The device comprises:

[0055] The module for determining the takeoff thrust in the increased lift state is used to determine the takeoff thrust P in the increased lift state of a transport aircraft with a single engine failure. xzon ;

[0056] Acceleration and flight path angle determination module, used to take off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb;

[0057] The takeoff field length determination module is used to calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula:

[0058]

[0059] Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, L R2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

[0060] Preferably, in the lift-up state takeoff thrust determination module, the lift-up state takeoff thrust P is determined by the following formula: xzon :

[0061]

[0062] Among them, n e is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

[0063] Preferably, the acceleration and track angle determination module includes:

[0064] Takeoff lift coefficient determination unit, used to determine the takeoff lift coefficient C in the increased lift state L ;

[0065] Takeoff drag coefficient determination unit, used to determine the takeoff drag coefficient C in the increased lift state D ;

[0066] The acceleration determination unit is used to determine the acceleration a of the conveyor by using the following formula:

[0067]

[0068] Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift;

[0069] The track angle determination unit is used to determine the track angle θ of the constant speed climb using the following formula:

[0070]

[0071] Preferably, in the takeoff lift coefficient determination unit, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L :

[0072]

[0073] Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap, C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

[0074] Preferably, the takeoff drag coefficient determination unit further comprises:

[0075] Roll moment trim drag coefficient determination subunit, used to determine the drag coefficient C generated by the roll moment trim when a single engine fails Da ;

[0076] The pitch moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure. De ;

[0077] The yaw moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the yaw moment trim of a single engine failure. Dr ;

[0078] The trim drag coefficient determination subunit is used to calculate the trim drag coefficient ΔC based on the following formula D :

[0079]

[0080] The takeoff drag coefficient determination subunit is used to calculate the takeoff drag coefficient C based on the following formula D :

[0081]

[0082] Among them, C Doff is the drag coefficient in the non-powered lift state, C Db It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

[0083] Preferably, in the roll moment trim drag coefficient determination subunit, the drag coefficient C generated by the roll moment trim due to a single engine failure is determined according to the following formula: Da :

[0084]

[0085] Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, Clδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

[0086] Preferably, the pitching moment trim drag coefficient determination subunit includes:

[0087] The first pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet vector effect. mp ;

[0088] The second pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet flap flow mb ;

[0089] The pitch moment coefficient determination unit is used to determine the pitch moment coefficient C for missed approach climb using the following formula m :

[0090] C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state;

[0091] The pitch moment trim drag coefficient determination unit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure using the following formula De :

[0092] C De =C Dδe δ e ;

[0093]

[0094] Among them, δ e Elevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

[0095] Preferably, in the first pitching moment coefficient increment determining unit, the pitching moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp :

[0096]

[0097] Among them, C Tis the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

[0098] Preferably, in the second pitching moment coefficient increment determining unit, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb :

[0099]

[0100] Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

[0101] Preferably, in the yaw moment trim drag coefficient determination subunit, the drag coefficient C generated by the yaw moment trim due to single engine failure is determined according to the following formula: Dr :

[0102]

[0103] Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

[0104] A third aspect of the present application provides a computer device comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for determining the length of a takeoff field for a transport aircraft with a single engine failure as described above.

[0105] A fourth aspect of the present application provides a readable storage medium storing a computer program, which, when executed by a processor, is used to implement the method for determining the length of a single-engine failure takeoff field for a transport aircraft as described above.

[0106] This application accurately describes the changes in thrust, lift, drag and speed of a blown flap powered lift transport aircraft during single-engine failure takeoff, and can quickly and accurately calculate the length of the lower surface blown flap powered lift transport aircraft's single-engine failure takeoff field. BRIEF DESCRIPTION OF THE DRAWINGS

[0107] Figure 1 It is a flow chart of a preferred embodiment of the method for determining the takeoff field length of a transport aircraft with a single engine failure in the present application.

[0108] Figure 2 It is a structural diagram of a computer device suitable for implementing the embodiments of the present application. DETAILED DESCRIPTION

[0109] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the implementation of this application will be described in more detail below in conjunction with the drawings in the implementation of this application. In the drawings, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and should not be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in conjunction with the drawings.

[0110] The first aspect of the present application provides a method for determining the takeoff field length of a transport aircraft with a single engine failure, which is applied to a power-assisted lift transport aircraft with blown flaps on the lower surface, such as Figure 1 As shown, the method mainly includes:

[0111] Step S1: Determine the takeoff thrust P of a transport aircraft in a lift-up state with a single engine failure. xzon ;

[0112] Step S2: Take-off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb;

[0113] Step S3: Calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula:

[0114]

[0115] Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, LR2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

[0116] This application first calculates the takeoff thrust in the increased lift state in step S1. Based on this, the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb are calculated in step S2. Finally, in step S3, the velocity V is integrated based on the transport aircraft's acceleration a to obtain the distance the transport aircraft has traveled on the ground, i.e., the first runway length. The flight altitude is then integrated based on the flight path angle to determine the second runway length required within the safe altitude range. The two runway lengths are combined to form the minimum required takeoff field length. This length can guide takeoff field design and can also be used to optimize aircraft parameters based on existing takeoff fields.

[0117] In some optional embodiments, in step S1, the takeoff thrust P in the increased lift state is determined by the following formula: xzon :

[0118]

[0119] Among them, n e is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

[0120] In some optional embodiments, step S2 further includes:

[0121] Step S21: Determine the takeoff lift coefficient C in the increased lift state L ;

[0122] Step S22: Determine the takeoff drag coefficient C in the increased lift state D ;

[0123] Step S23: Determine the acceleration a of the transport aircraft using the following formula:

[0124]

[0125] Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift;

[0126] Step S24: Determine the track angle θ of the constant speed climb using the following formula:

[0127]

[0128] In some optional embodiments, in step S21, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L :

[0129]

[0130] Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap (excluding the thrust vector part), C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

[0131] In some optional implementations, step S22 further includes:

[0132] Step S221: Determine the drag coefficient C generated by the rolling moment trim due to a single engine failure. Da ;

[0133] Step S222: Determine the drag coefficient C generated by the single engine failure pitching moment trim De ;

[0134] Step S223: Determine the drag coefficient C generated by the yaw moment trim due to single engine failure. Dr ;

[0135] Step S224: Calculate the trim resistance coefficient ΔC based on the following formula: D :

[0136]

[0137] Step S225: Calculate the takeoff drag coefficient C based on the following formula: D :

[0138]

[0139] Among them, C Doff is the drag coefficient in the non-powered lift state, CDb It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

[0140] In some optional embodiments, in step S221, the drag coefficient C generated by the single engine failure rolling moment trim is determined according to the following formula: Da :

[0141]

[0142] Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, C lδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

[0143] In some optional implementations, step S222 further includes:

[0144] Step S2221: Determine the pitch moment coefficient increment C generated by the jet vector effect mp ;

[0145] Step S2222: Determine the pitching moment coefficient increment C generated by the jet flap flow. mb ;

[0146] Step S2223: Determine the pitch moment coefficient C for the missed approach climb using the following formula: m :

[0147] C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state;

[0148] Step S2224: Determine the drag coefficient C generated by the single engine failure pitching moment trim using the following formula: De :

[0149] C De =C Dδe δ e ;

[0150]

[0151] Among them, δ eElevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

[0152] In some optional embodiments, in step S2221, the pitch moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp :

[0153]

[0154] Among them, C T is the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

[0155] In some optional embodiments, in step S2222, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb :

[0156]

[0157] Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

[0158] In some optional embodiments, in step S223, the drag coefficient C generated by the single engine failure yaw moment trim is determined according to the following formula: Dr :

[0159]

[0160] Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

[0161] For example, the aircraft in the calculation adopts the lower surface blown flap power lift technology, and the aircraft reference wing area is 353m 2 The aircraft has a wingspan of 50.6m, an aspect ratio of 7.25, a quarter-chord sweep angle of 21°, and a tip-to-root ratio of 0.24. Four high-bypass turbofan engines, each with a thrust of 185 kN, are suspended under the wings. The engine thrust axes are angled -5° relative to the local wing chord. The inboard engines are mounted at 29.6% of half-span, resulting in a 3° wing section angle. The outboard engines are mounted at 55% of half-span, resulting in a 2.5° wing section angle.

[0162] The aircraft's takeoff configuration includes leading-edge slats with a 15° deflection angle, double-slotted Fuller-type flaps with a 15° + 10° deflection angle, and an 8° downward inclination on the upper surface of the flap trailing edge. The chord length of the wing after flap extension is 1.2 times its original chord length, with the flap chord length being 32% of the wing chord length, of which the chord length of the second flap section is 7% of the wing chord length. The depth of the inboard flap portion immersed in the engine jet is 2.33 m, the diameter of the jet at the flap's trailing edge is 5.43 m, and the local wing chord length is 8.73 m. The depth of the outboard flap portion immersed in the engine jet is 2.1 m, the diameter of the jet at the flap's trailing edge is 4.89 m, and the local wing chord length is 6.48 m. The engine jet efficiency factor is 0.907, and the jet downward inclination angle is 12.25°.

[0163] Calculation status: takeoff weight 265t, system power extraction factor Ks is 3.6%, speed correction factor calculation model K v =1-0.167V / 80; the engine failure speed is 70m / s, the takeoff nose wheel speed is 77.5m / s, and the liftoff speed and safety altitude speed are 83m / s. The calculation content is as follows:

[0164] (1) Correction calculation of lift-drag characteristics in the increased lift state before engine failure (V = 30 m / s) to determine the takeoff drag coefficient C D is 0.1721;

[0165] (2) The acceleration a before the engine failed was 1.892 m / s 2 ;

[0166] (3) Correction calculation of lift-drag characteristics in the increased lift state after engine failure (V = 90 m / s) to determine the takeoff lift coefficient C in the increased lift state L The takeoff drag coefficient C in the increased lift state is 1.347. D is 0.1649;

[0167] (4) Calculation of the track angle for a constant-speed climb (V = 90 m / s) The track angle θ for a constant-speed climb is determined to be 1.956°.

[0168] In a second aspect, the present application provides a device for determining the takeoff field length of a transport aircraft with a single engine failure corresponding to the above method, which is applied to a power-assisted high-lift transport aircraft with blown flaps on the lower surface. The device comprises:

[0169] The module for determining the takeoff thrust in the increased lift state is used to determine the takeoff thrust P in the increased lift state of a transport aircraft with a single engine failure. xzon ;

[0170] Acceleration and flight path angle determination module, used to take off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb;

[0171] The takeoff field length determination module is used to calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula:

[0172]

[0173] Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, L R2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

[0174] In some optional embodiments, in the lift-up state takeoff thrust determination module, the lift-up state takeoff thrust P is determined by the following formula: xzon :

[0175]

[0176] Among them, n e is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

[0177] In some optional implementations, the acceleration and track angle determination module includes:

[0178] Takeoff lift coefficient determination unit, used to determine the takeoff lift coefficient C in the increased lift state L ;

[0179] Takeoff drag coefficient determination unit, used to determine the takeoff drag coefficient C in the increased lift state D ;

[0180] The acceleration determination unit is used to determine the acceleration a of the conveyor by using the following formula:

[0181]

[0182] Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift;

[0183] The track angle determination unit is used to determine the track angle θ of the constant speed climb using the following formula:

[0184]

[0185] In some optional embodiments, in the takeoff lift coefficient determination unit, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L :

[0186]

[0187] Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap, C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

[0188] In some optional embodiments, the takeoff drag coefficient determination unit further includes:

[0189] Roll moment trim drag coefficient determination subunit, used to determine the drag coefficient C generated by the roll moment trim when a single engine fails Da ;

[0190] The pitch moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure. De ;

[0191] The yaw moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the yaw moment trim of a single engine failure. Dr ;

[0192] The trim drag coefficient determination subunit is used to calculate the trim drag coefficient ΔC based on the following formula D :

[0193]

[0194] The takeoff drag coefficient determination subunit is used to calculate the takeoff drag coefficient C based on the following formula D :

[0195]

[0196] Among them, C Doff is the drag coefficient in the non-powered lift state, C Db It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

[0197] In some optional embodiments, in the roll moment trim drag coefficient determination subunit, the drag coefficient C generated by the roll moment trim due to a single engine failure is determined according to the following formula: Da :

[0198]

[0199] Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, C lδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

[0200] In some optional implementations, the pitching moment trim drag coefficient determination subunit includes:

[0201] The first pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet vector effect. mp ;

[0202] The second pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet flap flow mb ;

[0203] The pitch moment coefficient determination unit is used to determine the pitch moment coefficient C for missed approach climb using the following formula m :

[0204] C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state;

[0205] The pitch moment trim drag coefficient determination unit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure using the following formula De :

[0206] C De =C Dδe δ e ;

[0207]

[0208] Among them, δ e Elevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

[0209] In some optional embodiments, in the first pitching moment coefficient increment determining unit, the pitching moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp :

[0210]

[0211] Among them, C T is the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

[0212] In some optional embodiments, in the second pitching moment coefficient increment determining unit, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb :

[0213]

[0214] Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

[0215] In some optional embodiments, in the yaw moment trim drag coefficient determination subunit, the drag coefficient C generated by the yaw moment trim due to single engine failure is determined according to the following formula: Dr :

[0216]

[0217] Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

[0218] In a third aspect of the present application, a computer device includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement a method for determining the length of a takeoff field in the event of a single-engine failure of a transport aircraft.

[0219] In a fourth aspect, the present application provides a readable storage medium storing a computer program. When executed by a processor, the computer program is used to implement the method for determining the takeoff field length for a transport aircraft with a single engine failure, as described above. The computer-readable storage medium may be included in the apparatus described in the above embodiments, or it may exist independently and not be incorporated into the apparatus. The computer-readable storage medium carries one or more programs. When executed by the apparatus, the one or more programs process data according to the method described above.

[0220] Reference below Figure 2 , which shows a structural diagram of a computer device 400 suitable for implementing the embodiments of the present application. Figure 2 The computer device shown is only an example and should not limit the functions and scope of use of the embodiments of the present application.

[0221] like Figure 2As shown, computer device 400 includes a central processing unit (CPU) 401, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 402 or a program loaded from a storage portion 408 into a random access memory (RAM) 403. Various programs and data required for the operation of device 400 are also stored in RAM 403. CPU 401, ROM 402, and RAM 403 are connected to each other via a bus 404. An input / output (I / O) interface 405 is also connected to bus 404.

[0222] The following components are connected to the I / O interface 405: an input section 406 including a keyboard, a mouse, and the like; an output section 407 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and a speaker; a storage section 408 including a hard disk; and a communication section 409 including a network interface card such as a LAN card or a modem. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as needed. Removable media 411, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, is installed in the drive 410 as needed, so that computer programs read therefrom can be installed into the storage section 408 as needed.

[0223] In particular, according to the embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 409, and / or installed from the removable medium 411. When the computer program is executed by the central processing unit (CPU) 401, the above functions defined in the method of the present application are executed. It should be noted that the computer storage medium of the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, but not limited to, a system, device or component of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection having one or more conductors, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal may take a variety of forms, including, but not limited to, electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transfer a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code embodied on a computer-readable medium may be transmitted using any suitable medium, including, but not limited to, wireless, wire, optical cable, RF, etc., or any suitable combination thereof.

[0224] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, program segment or a part of code, and the module, program segment or a part of code includes one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a sequence different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs the specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0225] The modules or units described in the embodiments of this application may be implemented in software or hardware. The modules or units described may also be provided in a processor, and the names of these modules or units do not, in certain circumstances, limit the modules or units themselves.

[0226] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for determining the takeoff field length of a transport aircraft with a single engine failure, applied to a powered lift transport aircraft with blown flaps on the lower surface, characterized in that: The method includes: Step S1: Determine the takeoff thrust P of a transport aircraft in a lift-up state with a single engine failure. xzon ; Step S2: Take-off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb; Step S3: Calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula: L X =L R1 +L R2 +L L-R +L C Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, L R2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

2. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 1, wherein: In step S1, the takeoff thrust P in the increased lift state is determined by the following formula: xzon : P xzon =n e P xz or j cos(α+θ j ) V<V EF P xzon =(n e -1)P emax (1-K s )K v K h V≥V EF P xz =P emax (1-K s )K v K h q=0.5ρV 2 Among them, n e is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

3. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 1, wherein: Step S2 further comprises: Step S21: Determine the takeoff lift coefficient C in the increased lift state L ; Step S22: Determine the takeoff drag coefficient C in the increased lift state D ; Step S23: Determine the acceleration a of the transport aircraft using the following formula: Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift; Step S24: Determine the track angle θ of the constant speed climb using the following formula:

4. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 3, wherein: In step S21, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L : Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap, C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

5. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 3, wherein: The step S22 further includes: Step S221: Determine the drag coefficient C generated by the rolling moment trim due to a single engine failure. Da ; Step S222: Determine the drag coefficient C generated by the single engine failure pitching moment trim De ; Step S223: Determine the drag coefficient C generated by the yaw moment trim due to single engine failure. Dr ; Step S224: Calculate the trim resistance coefficient ΔC based on the following formula: D : Step S225: Calculate the takeoff drag coefficient C based on the following formula: D : Among them, C Doff is the drag coefficient in the non-powered lift state, C Db It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

6. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 5, wherein: In step S221, the drag coefficient C generated by the single engine failure rolling moment trim is determined according to the following formula: Da : Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, C lδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

7. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 5, wherein: Step S222 further includes: Step S2221: Determine the pitch moment coefficient increment C generated by the jet vector effect mp ; Step S2222: Determine the pitching moment coefficient increment C generated by the jet flap flow. mb ; Step S2223: Determine the pitch moment coefficient C for the missed approach climb using the following formula: m : C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state; Step S2224: Determine the drag coefficient C generated by the single engine failure pitching moment trim using the following formula: De : C De =C Dδe d e ; Among them, δ e Elevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

8. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 7, wherein: In step S2221, the pitch moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp : Among them, C T is the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

9. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 7, wherein: In step S2222, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb : Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

10. The method for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 5, wherein: In step S223, the drag coefficient C generated by the single engine failure yaw moment trim is determined according to the following formula: Dr : Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

11. A device for determining the takeoff field length of a transport aircraft with a single engine failure, applied to a power-lift transport aircraft with blown flaps on the lower surface, characterized in that: The device includes: The module for determining the takeoff thrust in the increased lift state is used to determine the takeoff thrust P in the increased lift state of a transport aircraft with a single engine failure. xzon ; Acceleration and flight path angle determination module, used to take off thrust P according to the lift state xzon Determine the transport aircraft's acceleration a and the flight path angle θ for a constant-speed climb; The takeoff field length determination module is used to calculate the length L of the transport aircraft's single-engine failure takeoff field according to the following integral formula: Among them, V EF is the engine failure speed, V R V is the nose wheel lift speed for takeoff. lof is the takeoff speed, L R1 is the ground rolling distance before engine failure, L R2 L is the ground rolling distance before engine failure and nose wheel rotation for takeoff, L-R L is the rolling distance between the front wheel lift and the departure point, C is the flight distance to climb to a safe altitude, and V is the speed of the transport aircraft.

12. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 11, wherein: In the lift-up state takeoff thrust determination module, the lift-up state takeoff thrust P is determined by the following formula: xzon : Among them, n e is the number of engines, P emax is the maximum thrust of the engine at takeoff, K s is the takeoff system power extraction factor, K v is the speed correction factor for takeoff thrust, K h is the altitude correction factor for takeoff thrust, P xz is the engine thrust corrected for power, speed, and altitude, η j is the engine jet efficiency factor, θ j is the downward deflection angle of the jet flow disturbed by the flap relative to the fuselage axis, α is the fuselage angle of attack, C T is the aircraft takeoff thrust coefficient, S ref is the reference area of ​​the wing, ρ is the air density, and q is the velocity pressure.

13. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 11, wherein: The acceleration and track angle determination module includes: Takeoff lift coefficient determination unit, used to determine the takeoff lift coefficient C in the increased lift state L ; Takeoff drag coefficient determination unit, used to determine the takeoff drag coefficient C in the increased lift state D ; The acceleration determination unit is used to determine the acceleration a of the conveyor by using the following formula: Where W is the takeoff weight of the aircraft, D is the takeoff aerodynamic drag, L is the takeoff aerodynamic lift, F is the friction force of the runway, f is the rolling friction coefficient of the runway, and Z is the takeoff weight of the aircraft. p is the component of thrust in the direction of lift; The track angle determination unit is used to determine the track angle θ of the constant speed climb using the following formula:

14. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 13, wherein: In the takeoff lift coefficient determination unit, the takeoff lift coefficient C in the increased lift state is determined by the following formula: L : Among them, C Loff is the takeoff lift coefficient in the non-powered lift state, C Lb is the lift coefficient increment generated by the full-engine takeoff jet flow around the flap, C Lθ C is the reference value of the lift coefficient increment generated by the jet flap flow, Lα is the correction value for the effect of angle of attack.

15. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 13, wherein: The takeoff drag coefficient determination unit further includes: Roll moment trim drag coefficient determination subunit, used to determine the drag coefficient C generated by the roll moment trim when a single engine fails Da ; The pitch moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure. De ; The yaw moment trim drag coefficient determination subunit is used to determine the drag coefficient C generated by the yaw moment trim of a single engine failure. Dr ; The trim drag coefficient determination subunit is used to calculate the trim drag coefficient ΔC based on the following formula D : The takeoff drag coefficient determination subunit is used to calculate the takeoff drag coefficient C based on the following formula D : Among them, C Doff is the drag coefficient in the non-powered lift state, C Db It is the power impact correction value of the drag coefficient in the full-engine takeoff lift state.

16. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 15, wherein: In the roll moment trim drag coefficient determination subunit, the drag coefficient C generated by the roll moment trim due to single engine failure is determined according to the following formula: Da : Among them, δ a Aileron deflection angle for rolling moment balancing, C Dδa is the increase in drag coefficient caused by aileron unit deflection angle, C l is the rolling moment coefficient caused by single engine failure, C lδa is the aileron control efficiency, ΔC L is the loss of lift coefficient of the wing on the side of the failed engine, L ye is the span length between the axis of the failed engine and the axis of the fuselage, b w The wing span.

17. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 15, wherein: The pitching moment trim drag coefficient determination subunit includes: The first pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet vector effect. mp ; The second pitch moment coefficient increment determination unit is used to determine the pitch moment coefficient increment C generated by the jet flap flow mb ; The pitch moment coefficient determination unit is used to determine the pitch moment coefficient C for missed approach climb using the following formula m : C m =C moff +C mp +C mb Among them, C moff The pitching moment for takeoff climb in non-powered-up state; The pitch moment trim drag coefficient determination unit is used to determine the drag coefficient C generated by the pitch moment trim of a single engine failure using the following formula De : C De =C Dδe d e ; Among them, δ e Elevator deflection angle to balance the pitch moment, C Dδe is the drag coefficient generated by the unit deflection angle of the elevator, C mδe The control efficiency of the elevator.

18. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 17, wherein: In the first pitching moment coefficient increment determination unit, the pitching moment coefficient increment C generated by the jet vector effect is determined by the following formula: mp : Among them, C T is the thrust coefficient for takeoff of an aircraft with one engine failure, θ e is the downward deflection angle of the engine axis relative to the fuselage axis, h cf L is the vertical distance of the flap aerodynamic pressure center below the center of gravity, f The axial distance behind the center of gravity of the flap's aerodynamic pressure center, h e is the vertical distance of the engine nozzle below the center of gravity, L e is the axial distance of the engine nozzle behind the center of gravity, c a is the average aerodynamic chord length of the wing.

19. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 17, wherein: In the second pitching moment coefficient increment determination unit, the pitching moment coefficient increment C generated by the jet flap flow is determined by the following formula: mb : Among them, L0 is the axial distance between the leading edge of the wing and the center of gravity of the fuselage at the engine installation position. It is positive if it is located behind the center of gravity. L c is the axial distance behind the center of gravity of the wing's aerodynamic pressure center after the flaps are placed, and c' is the axial projection length of the wing's chord length at the engine installation position.

20. The device for determining the takeoff field length of a transport aircraft with a single engine failure according to claim 15, wherein: In the yaw moment trim drag coefficient determination subunit, the drag coefficient C generated by the yaw moment trim due to single engine failure is determined according to the following formula: Dr : Among them, δ r The rudder deflection angle to balance the yaw moment, C Dδr is the drag coefficient generated by the rudder unit deflection angle, C n is the yaw moment coefficient caused by single engine failure, C nδr The control efficiency of the rudder.

21. A computer device, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for determining the length of the takeoff field with a single engine failure of a transport aircraft as described in any one of claims 1 to 10.

22. A readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it is used to implement the method for determining the length of the take-off field with a single engine failure of a transport aircraft as described in any one of claims 1 to 10.

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