Method and device for determining power influence correction of pitch moment coefficient of a transport aircraft

Abstract

The application belongs to the technical field of aircraft design, and particularly relates to a method and device for determining a power influence correction amount of a pitching moment coefficient of a transport aircraft, and is applied to a lower surface air-blowing flap power increasing transport aircraft. The method comprises the following steps: S1, determining a pitching moment coefficient increment generated by a flow lift increment of a jet flap; S2, determining a pitching moment coefficient increment generated by a thrust vector effect; and S3, determining that the power influence correction amount of the pitching moment coefficient is the sum of the pitching moment coefficient increment generated by the flow lift increment of the jet flap and the pitching moment coefficient increment generated by the thrust vector effect. The application can quickly and accurately calculate the power influence correction amount of the pitching moment coefficient of a take-off and landing configuration of the lower surface air-blowing flap power increasing transport aircraft.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft design, and in particular relates to a method and device for determining a dynamic influence correction value of a pitch moment coefficient of a transport aircraft. Background Art

[0002] The effect of power on the pitching moment of conventional aircraft is minimal. However, in aircraft with blown flaps for power-enhanced takeoff and landing, the flaps are immersed in the engine jet. The resulting lift increase caused by the flaps interferes with the jet flow, creating a nose-down moment that increases aerodynamic trim losses during takeoff and landing. Accurately calculating the effect of power on pitching moment is essential to improving aerodynamic performance and optimizing the takeoff and landing configuration. Summary of the Invention

[0003] In order to solve the above problems, the present application provides a method and device for determining the dynamic influence correction value of the pitch moment coefficient of a transport aircraft, providing technical support for the calculation and evaluation of the pitch moment characteristics of the take-off and landing configuration of a power-enhanced transport aircraft with lower surface blown flaps.

[0004] In a first aspect, the present application provides a method for determining a dynamic influence correction value of a transport aircraft pitching moment coefficient, which is applied to a power-assisted lift transport aircraft with blown flaps on the lower surface. The method comprises:

[0005] Step S1: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the jet flap. mb ;

[0006] Step S2: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect mp ;

[0007] Step S3: Determine the dynamic influence correction value ΔC of the pitching moment coefficient m for:

[0008] ΔC m =ΔC mb +ΔC mp .

[0009] Preferably, step S1 further comprises:

[0010] Step S11: Obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are deployed. c , the average aerodynamic chord length of the wing c a ;

[0011] Step S12: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb ;

[0012] Step S13: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow.mb for:

[0013]

[0014] Preferably, step S12 further includes:

[0015] Step S121, calculate the wingspan factor φ and the engine tail jet momentum coefficient C of the jet flow μ ;

[0016] Step S122: Based on the wingspan factor φ of the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value of the lift coefficient increment of the jet flap flow △C Lθ ;

[0017] Step S123: Determine the lift coefficient angle of attack increment correction value ΔC based on the wingspan factor φ affected by the jet flow. Lα ;

[0018] Step S124: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb for:

[0019] ΔC Lb =ΔC Lθ +ΔC Lα .

[0020] Preferably, in step S121, the span factor φ affected by the jet flow is determined by the following formula:

[0021] φ=φ o -φ i ;

[0022] Among them, φ o is the spanwise influence factor of the outer engine jet, φ i is the spanwise influence factor of the inboard engine jet.

[0023] Preferably, in step S121, the engine tail jet momentum coefficient C is determined by the following formula: μ :

[0024]

[0025]

[0026] Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis, n e is the number of engines, Sref is the wing reference area, C T is the thrust coefficient of the aircraft;

[0027] When F < 1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H f is the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

[0028] Preferably, step S2 further comprises:

[0029] Step S21: Determine the engine jet efficiency factor η j ;

[0030] Step S22: Determine the downward deflection angle θ of the jet axis relative to the fuselage axis after the engine jet is deflected by the flap interference. j ;

[0031] Step S23: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect according to the following formula: mp :

[0032]

[0033]

[0034]

[0035] q=0.5ρV 2

[0036] Among them, C T is the thrust coefficient of the aircraft, P e is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

[0037] Preferably, in step S21, the engine jet efficiency factor η is determined by the following formula: j :

[0038]

[0039] Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d =0, θ jc =0, when λ1=1 and θ d ≠0, θ jc =θ d ,on the contrary:

[0040]

[0041]

[0042]

[0043] Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

[0044] Preferably, in step S22, the lower deflection angle θ is determined by the following formula: j :

[0045] θ j =θ jw +θ wi ;

[0046] Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

[0047] A second aspect of the present application provides a device for determining a dynamic influence correction value of a pitching moment coefficient of a transport aircraft, which is applied to a power-assisted lift transport aircraft with blown flaps on the lower surface. The device comprises:

[0048] The first pitching moment coefficient increment determination module is used to determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the pitching moment coefficient. mb ;

[0049] The second pitch moment coefficient increment determination module is used to determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect. mp ;

[0050] Dynamic influence correction calculation module, used to determine the dynamic influence correction value ΔC of the pitch moment coefficient m for:

[0051] ΔC m =ΔC mb +ΔC mp .

[0052] Preferably, the first pitching moment coefficient increment determining module includes:

[0053] The wing parameter acquisition unit is used to obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are released. c , the average aerodynamic chord length of the wing c a ;

[0054] The lift coefficient increment determination unit is used to determine the lift coefficient increment ΔC generated by the jet flap flow Lb ;

[0055] The first pitching moment coefficient increment calculation unit is used to determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow mb for:

[0056]

[0057] Preferably, the lift coefficient increment determining unit includes:

[0058] The wingspan factor and momentum coefficient calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ ;

[0059] The reference value calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value ΔC of the lift coefficient increment of the flow around the jet flap Lθ ;

[0060] The correction value calculation subunit is used to determine the angle of attack increment correction value ΔC of the lift coefficient based on the wingspan factor φ affected by the jet Lα ;

[0061] The lift coefficient increment determination subunit is used to determine the lift coefficient increment ΔC generated by the jet flap flow Lb for:

[0062] ΔC Lb =ΔC Lθ +ΔC Lα .

[0063] Preferably, in the wingspan factor and momentum coefficient calculation subunit, the wingspan factor φ affected by the jet flow is determined by the following formula:

[0064] φ=φ o -φ i ;

[0065] Among them, φ o is the spanwise influence factor of the outer engine jet, φ i is the spanwise influence factor of the inboard engine jet.

[0066] Preferably, in the wingspan factor and momentum coefficient calculation subunit, the engine tail jet momentum coefficient C is determined by the following formula: μ :

[0067]

[0068]

[0069] Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis, n e is the number of engines, S ref is the wing reference area, C T is the thrust coefficient of the aircraft;

[0070] When F < 1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H f is the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

[0071] Preferably, the second pitching moment coefficient increment determining module includes:

[0072] The jet efficiency factor determination subunit is used to determine the engine jet efficiency factor η j ;

[0073] The downward deflection angle determination subunit is used to determine the downward deflection angle θ of the axis relative to the fuselage axis after the engine jet is deflected by the flap interference j ;

[0074] The pitch moment coefficient increment determination subunit is used to determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect according to the following formula mp :

[0075]

[0076]

[0077]

[0078] q=0.5ρV 2

[0079] Among them, C T is the thrust coefficient of the aircraft, Pe is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

[0080] Preferably, in the jet efficiency factor determination subunit, the engine jet efficiency factor η is determined by the following formula: j :

[0081]

[0082] Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d =0, θ jc =0, when λ1=1 and θ d ≠0, θ jc =θ d ,on the contrary:

[0083]

[0084]

[0085]

[0086] Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

[0087] Preferably, in the lower deflection angle determination subunit, the lower deflection angle θ is determined by the following formula: j :

[0088] θ j =θ jw +θ wi ;

[0089] Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

[0090] A third aspect of the present application provides a computer device comprising a processor, a memory, and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the method for determining the dynamic influence correction amount of the pitch moment coefficient of a transport aircraft as described above.

[0091] In a fourth aspect, the present application provides a readable storage medium storing a computer program. When the computer program is executed by a processor, it is used to implement the method for determining the dynamic influence correction amount of the pitch moment coefficient of the transport aircraft as described above.

[0092] The present application can quickly and accurately calculate the dynamic influence correction amount of the pitch moment coefficient of the take-off and landing configuration of a powered lift transport aircraft with blown flaps on the lower surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Figure 1 It is a flow chart of a preferred embodiment of the method for determining the dynamic influence correction amount of the pitch moment coefficient of the transport aircraft of the present application.

[0094] Figure 2 It is a structural diagram of a computer device suitable for implementing the embodiments of the present application. DETAILED DESCRIPTION

[0095] 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.

[0096] The first aspect of the present application provides a method for determining a dynamic influence correction value of a transport aircraft pitch moment coefficient, 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:

[0097] Step S1: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the jet flap. mb ;

[0098] Step S2: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect mp ;

[0099] Step S3: Determine the dynamic influence correction value ΔC of the pitching moment coefficient m for:

[0100] ΔC m =ΔC mb +ΔC mp .

[0101] In some optional embodiments, step S1 further includes:

[0102] Step S11: Obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are deployed. c , the average aerodynamic chord length of the wing c a ;

[0103] Step S12: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb ;

[0104] Step S13: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow. mb for:

[0105]

[0106] In this embodiment, L c =0.5c'; c' is the axial projection length of the wing chord length (flaps deployed) at the engine installation position.

[0107] In some optional implementations, step S12 further includes:

[0108] Step S121, calculate the wingspan factor φ and the engine tail jet momentum coefficient C of the jet flow μ ;

[0109] Step S122: Based on the wingspan factor φ of the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value ΔC of the lift coefficient increment of the flow around the jet flap Lθ ;

[0110] Step S123: Determine the lift coefficient angle of attack increment correction value ΔC based on the wingspan factor φ affected by the jet flow. Lα ;

[0111] Step S124: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb for:

[0112] ΔC Lb =ΔC Lθ +ΔC Lα .

[0113] In some optional implementations, in step S121, the span factor φ of the jet flow is determined by the following formula:

[0114] φ=φ o -φ i ;

[0115] Among them, φ o is the spanwise influence factor of the outboard engine jet, φ i is the spanwise influence factor of the inboard engine jet.

[0116] In this embodiment, φ o The spanwise relative position η of the outer boundary line of the outer engine jet at the flap trailing edge o The interpolation calculation is obtained in the first two-dimensional interpolation table composed of ATH. Similarly, φ i The spanwise relative position η of the inner boundary line of the inner engine jet at the flap trailing edge i It is obtained by interpolation calculation in the second two-dimensional interpolation table composed of ATH. Among them:

[0117]

[0118]

[0119]

[0120] ATH=ARtanΛ 1 / 2 -8λ;

[0121] Among them, X eo 、X ei They are the outer and inner engine wing span installation positions respectively. jo 、D ji are the diameters of the outer and inner engine jets at the trailing edge of the flaps, respectively. s is the wing span b w Half of the length, that is, half the length. 1 / 2 is the 1 / 2 chord sweep angle of the wing, and λ is the wing tip-to-root ratio.

[0122] For example, the first two-dimensional interpolation table is shown in Table 1 below.

[0123] Table 1 First two-dimensional interpolation table

[0124]

[0125] In some optional embodiments, in step S121, the engine tail jet momentum coefficient C is determined by the following formula: μ :

[0126]

[0127]

[0128] Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis (flaps extended), n e is the number of engines, S ref is the wing reference area, C T is the thrust coefficient of the aircraft;

[0129] When F < 1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H f is the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

[0130] Then, in step S122, the reference value ΔC of the lift coefficient increment of the jet flap flow is calculated according to the following formula: Lθ :

[0131]

[0132]

[0133]

[0134]

[0135]

[0136] Where K1 is a function of the momentum coefficient, G1 is a function of the wing aspect ratio AR and the parameter K2, K2 is the ratio of the flap extended chord length to the original chord length; θ f is the downward deflection angle of the upper surface of the trailing edge of the second flap relative to the chord, θ faux c is the downward angle of the chord line of the second flap relative to the chord line of the front flap; f is the sum of the chord lengths of the two flaps, c faux is the chord length of the second flap, c' is the chord length of the wing after the flaps are extended, and c is the chord length of the wing before the flaps are extended. K 3aux and K3 are functions of the momentum coefficient and the relative chord length of the flap, obtained by interpolation.

[0137] In step S123, the lift coefficient angle of attack increment correction value ΔC is calculated according to the following formula: Lα :

[0138]

[0139] Among them, θ wi is the installation angle of the engine axis relative to the wing section relative to the fuselage axis, The relative thickness of the wing with flaps extended.

[0140] In some optional embodiments, step S2 further includes:

[0141] Step S21: Determine the engine jet efficiency factor η j ;

[0142] Step S22: Determine the downward deflection angle θ of the jet axis relative to the fuselage axis after the engine jet is deflected by the flap interference. j ;

[0143] Step S23: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect according to the following formula: mp :

[0144]

[0145]

[0146]

[0147] q=0.5ρV 2

[0148] Among them, C T is the thrust coefficient of the aircraft, P e is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

[0149] In some optional embodiments, in step S21, the engine jet efficiency factor η is determined by the following formula: j :

[0150]

[0151] Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d=0, θ jc =0, when λ1=1 and θ d ≠0, θ jc =θ d ,on the contrary:

[0152]

[0153]

[0154]

[0155] Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

[0156] In some optional embodiments, in step S22, the lower deflection angle θ is determined by the following formula: j :

[0157] θ j =θ jw +θ wi ;

[0158] Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

[0159] In this embodiment, θ jw =θ d +θ ew ;

[0160] θ d =asin(sibsinθ m );

[0161] θ m =θ f -θ ew ;

[0162] θ f =δ f +θ fte ;

[0163] θ e =θ ew +θ wi

[0164] Among them, δ f is the flap downward deflection angle, θ fte is the angle between the upper surface of the flap trailing edge and the flap chord, θ ew is the downward angle of the engine axis relative to the wing chord line, θ m is the downward deflection angle of the flap relative to the engine axis, θ dis the deflection angle of the jet disturbed by the flap, and the parameter sib is obtained by interpolation from the given interpolation table.

[0165] In a second aspect, the present application provides a device for determining a dynamic influence correction value of a transport aircraft pitching moment coefficient corresponding to the above method, which is applied to a power-assisted lift transport aircraft with blown flaps on the lower surface. The device comprises:

[0166] The first pitching moment coefficient increment determination module is used to determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the pitching moment coefficient. mb ;

[0167] The second pitch moment coefficient increment determination module is used to determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect. mp ;

[0168] Dynamic influence correction calculation module, used to determine the dynamic influence correction value ΔC of the pitch moment coefficient m for:

[0169] ΔC m =ΔC mb +ΔC mp .

[0170] In some optional implementations, the first pitching moment coefficient increment determination module includes:

[0171] The wing parameter acquisition unit is used to obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are released. c , the average aerodynamic chord length of the wing c a ;

[0172] The lift coefficient increment determination unit is used to determine the lift coefficient increment ΔC generated by the jet flap flow Lb ;

[0173] The first pitching moment coefficient increment calculation unit is used to determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow mb for:

[0174]

[0175] In some optional embodiments, the lift coefficient increment determining unit includes:

[0176] The wingspan factor and momentum coefficient calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ ;

[0177] The reference value calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value ΔC of the lift coefficient increment of the flow around the jet flap Lθ ;

[0178] The correction value calculation subunit is used to determine the angle of attack increment correction value ΔC of the lift coefficient based on the wingspan factor φ affected by the jet Lα ;

[0179] The lift coefficient increment determination subunit is used to determine the lift coefficient increment ΔC generated by the jet flap flow Lb for:

[0180] ΔC Lb =ΔC Lθ +ΔC Lα .

[0181] In some optional embodiments, in the wingspan factor and momentum coefficient calculation subunit, the wingspan factor φ affected by the jet flow is determined by the following formula:

[0182] φ=φ o -φ i ;

[0183] Among them, φ o is the spanwise influence factor of the outer engine jet, φ i is the spanwise influence factor of the inboard engine jet.

[0184] In some optional embodiments, in the wingspan factor and momentum coefficient calculation subunit, the engine tail jet momentum coefficient C is determined by the following formula: μ :

[0185]

[0186]

[0187] Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis, n e is the number of engines, S ref is the wing reference area, C T is the thrust coefficient of the aircraft;

[0188] When F < 1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H fis the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

[0189] In some optional implementations, the second pitching moment coefficient increment determination module includes:

[0190] The jet efficiency factor determination subunit is used to determine the engine jet efficiency factor η j ;

[0191] The downward deflection angle determination subunit is used to determine the downward deflection angle θ of the axis relative to the fuselage axis after the engine jet is deflected by the flap interference j ;

[0192] The pitch moment coefficient increment determination subunit is used to determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect according to the following formula mp :

[0193]

[0194]

[0195]

[0196] q=0.5ρV 2

[0197] Among them, C T is the thrust coefficient of the aircraft, P e is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

[0198] In some optional embodiments, in the jet efficiency factor determination subunit, the engine jet efficiency factor η is determined by the following formula: j :

[0199]

[0200] Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d =0, θ jc =0, when λ1=1 and θ d≠0, θ jc =θ d ,on the contrary:

[0201]

[0202]

[0203]

[0204] Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

[0205] In some optional embodiments, in the lower deflection angle determination subunit, the lower deflection angle θ is determined by the following formula: j :

[0206] θ j =θ jw +θ wi ;

[0207] Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

[0208] 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 a dynamic influence correction value of a pitch moment coefficient of a transport aircraft.

[0209] 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 dynamic influence correction value of the pitching moment coefficient of a transport aircraft 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.

[0210] 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.

[0211] 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.

[0212] 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.

[0213] 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.

[0214] 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.

[0215] 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.

[0216] 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 dynamic influence correction value of the pitch moment coefficient of a transport aircraft, applied to a power-lift transport aircraft with blown flaps on the lower surface, characterized in that: The method includes: Step S1: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the jet flap. mb ; Step S2: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect mp ; Step S3: Determine the dynamic influence correction value ΔC of the pitching moment coefficient m for: △C m =△C mb +△C mp ; Wherein, step S1 further includes: Step S11: Obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are deployed. c , the average aerodynamic chord length of the wing c a ; Step S12: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb ; Step S13: Determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow. mb for: Step S2 further comprises: Step S21: Determine the engine jet efficiency factor η j ; Step S22: Determine the downward deflection angle θ of the jet axis relative to the fuselage axis after the engine jet is deflected by the flap interference. j ; Step S23: Determine the pitch moment coefficient increment ΔC generated by the thrust vectoring effect according to the following formula: mp : Among them, C T is the thrust coefficient of the aircraft, P e is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

2. The method for determining the dynamic influence correction value of the pitching moment coefficient of a transport aircraft according to claim 1, characterized in that: Step S12 further includes: Step S121, calculate the wingspan factor φ and the engine tail jet momentum coefficient C of the jet flow μ ; Step S122: Based on the wingspan factor φ of the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value of the lift coefficient increment of the jet flap flow △C Lθ ; Step S123: Determine the lift coefficient angle of attack increment correction value ΔC based on the wingspan factor φ affected by the jet flow. Lα ; Step S124: Determine the lift coefficient increment ΔC generated by the jet flap flow Lb for: △C Lb =△C Lθ +△C Lα 。 3. The method for determining the dynamic influence correction value of the pitching moment coefficient of a transport aircraft according to claim 2, characterized in that: In step S121, the wingspan factor φ affected by the jet flow is determined by the following formula: f=f o -f i ; Among them, φ o is the spanwise influence factor of the outer engine jet, φ i is the spanwise influence factor of the inboard engine jet.

4. The method for determining the dynamic influence correction value of the pitching moment coefficient of a transport aircraft according to claim 2, characterized in that: In step S121, the engine tail jet momentum coefficient C is determined by the following formula: μ : Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis, n e is the number of engines, S ref is the wing reference area, C T is the thrust coefficient of the aircraft; When F<1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H f is the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

5. The method for determining the dynamic influence correction value of the pitching moment coefficient of a transport aircraft according to claim 1, characterized in that: In step S21, the engine jet efficiency factor η is determined by the following formula: j : Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d =0, θ jc =0, when λ1=1 and θ d ≠0, θ jc =θ d ,on the contrary: Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

6. The method for determining the dynamic influence correction value of the pitching moment coefficient of a transport aircraft according to claim 1, characterized in that: In step S22, the lower deflection angle θ is determined by the following formula: j : i j =θ jw +θ wi ; Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

7. A device for determining the dynamic influence correction value of the pitch moment coefficient of a transport aircraft, applied to a power-lift transport aircraft with blown flaps on the lower surface, characterized in that: The device includes: The first pitching moment coefficient increment determination module is used to determine the pitching moment coefficient increment ΔC generated by the lift increment of the jet flap flow around the mb ; The second pitch moment coefficient increment determination module is used to determine the pitch moment coefficient increment △C generated by the thrust vectoring effect mp ; Dynamic influence correction calculation module, used to determine the dynamic influence correction value △C of the pitch moment coefficient m for: △C m =△C mb +△C mp ; Wherein, the first pitching moment coefficient increment determination module includes: The wing parameter acquisition unit is used to obtain the axial distance L0 between the leading edge of the wing at the engine installation position and the center of gravity, and the axial distance L between the aerodynamic pressure center of the wing and the center of gravity after the flaps are released. c , the average aerodynamic chord length of the wing c a ; The lift coefficient increment determination unit is used to determine the lift coefficient increment △C generated by the jet flap flow Lb ; The first pitching moment coefficient increment calculation unit is used to determine the pitching moment coefficient increment △C generated by the lift increment of the jet flap flow around mb for: The second pitching moment coefficient increment determination module includes: The jet efficiency factor determination subunit is used to determine the engine jet efficiency factor η j ; The downward deflection angle determination subunit is used to determine the downward deflection angle θ of the axis relative to the fuselage axis after the engine jet is deflected by the flap interference j ; The pitch moment coefficient increment determination subunit is used to determine the pitch moment coefficient increment △C generated by the thrust vectoring effect according to the following formula mp : Among them, C T is the thrust coefficient of the aircraft, P e is the engine thrust, ρ is the air density, V is the airspeed, q is the velocity pressure, 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 It is the axial distance of the engine nozzle behind the center of gravity.

8. The transport aircraft pitching moment coefficient dynamic influence correction value determining device according to claim 7, characterized in that: The lift coefficient increment determination unit includes: The wingspan factor and momentum coefficient calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ ; The reference value calculation subunit is used to calculate the wingspan factor φ affected by the jet flow and the engine tail jet momentum coefficient C μ Determine the reference value of the lift coefficient increment of the jet flap flow △C Lθ ; The correction value calculation subunit is used to determine the angle of attack increment correction value △C of the lift coefficient based on the wingspan factor φ affected by the jet Lα ; The lift coefficient increment determination subunit is used to determine the lift coefficient increment △C generated by the jet flap flow Lb for: △C Lb =△C Lθ +△C Lα 。 9. The transport aircraft pitching moment coefficient dynamic influence correction value determining device according to claim 8, characterized in that: In the wingspan factor and momentum coefficient calculation subunit, the wingspan factor φ affected by the jet is determined by the following formula: f=f o -f i ; Among them, φ o is the spanwise influence factor of the outer engine jet, φ i is the spanwise influence factor of the inboard engine jet.

10. The transport aircraft pitching moment coefficient dynamic influence correction value determination device according to claim 8, characterized in that: In the wingspan factor and momentum coefficient calculation subunit, the engine tail jet momentum coefficient C is determined by the following formula: μ : Among them, S j is the sum of the wing areas affected by all engine jets, D j is the diameter of the engine i jet at the trailing edge of the flap, c' i is the chord length of the wing section corresponding to the engine i axis, n e is the number of engines, S ref is the wing reference area, C T is the thrust coefficient of the aircraft; When F<1.0, When F≥1.0, λ1=1; where Y=1-2F, F is the jet immersion factor of the flap, H f is the jet immersion depth of the flap, and λ2 is determined by the downward deflection angle θ of the flap relative to the engine axis. m Obtained by interpolation calculation.

11. The transport aircraft pitching moment coefficient dynamic influence correction value determining device according to claim 7, characterized in that: In the jet efficiency factor determination subunit, the engine jet efficiency factor η is determined by the following formula: j : Among them, θ jc is the theoretical deflection angle of the engine jet caused by flap interference, when λ1=1 and θ d =0, θ jc =0, when λ1=1 and θ d ≠0, θ jc =θ d ,on the contrary: Among them, θ d is the deflection angle of the engine jet disturbed by the flaps.

12. The transport aircraft pitching moment coefficient dynamic influence correction value determining device according to claim 7, characterized in that: In the lower deflection angle determination subunit, the lower deflection angle θ is determined by the following formula: j : i j =θ jw +θ wi ; Among them, θ jw is the downward deflection angle of the engine jet relative to the wing chord line, θ wi The installation angle of the wing section at the engine installation location.

13. 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 dynamic influence correction amount of the pitching moment coefficient of a transport aircraft according to any one of claims 1 to 6.

14. 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 dynamic influence correction amount of the pitching moment coefficient of a transport aircraft according to any one of claims 1 to 6.

Images