CN113772115B - Design method for controlling deflection angle of rear-mounted horizontal tail control surface of helicopter - Google Patents

Design method for controlling deflection angle of rear-mounted horizontal tail control surface of helicopter Download PDF

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CN113772115B
CN113772115B CN202111337930.2A CN202111337930A CN113772115B CN 113772115 B CN113772115 B CN 113772115B CN 202111337930 A CN202111337930 A CN 202111337930A CN 113772115 B CN113772115 B CN 113772115B
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helicopter
horizontal tail
wind speed
steps
rotor
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CN113772115A (en
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王畅
黄明其
徐栋霞
彭先敏
袁红刚
杨永东
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Low Speed Aerodynamics Institute of China Aerodynamics Research and Development Center
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Low Speed Aerodynamics Institute of China Aerodynamics Research and Development Center
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64FGROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
    • B64F5/00Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64FGROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
    • B64F5/00Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
    • B64F5/60Testing or inspecting aircraft components or systems
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M9/00Aerodynamic testing; Arrangements in or on wind tunnels

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Transportation (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)

Abstract

The invention discloses a design method for controlling the deflection angle of a rear-mounted horizontal tail control surface of a helicopter, which comprises the following steps: s1, carrying out a balancing wind tunnel test on the helicopter model without the horizontal tail to obtain the full-helicopter pitching moment and attitude angle under the condition that the horizontal tail is not installed on the helicopter at different wind speeds; and S2, adding a horizontal tail to the helicopter model in the step S1, adjusting the deflection angle of the horizontal tail, and performing a balancing wind tunnel test on the helicopter model added with the horizontal tail. The invention improves the design efficiency, avoids solving the problems in the flight test process after the helicopter is developed, and solves the problems of repeated design, influence on the development progress and the like.

Description

Design method for controlling deflection angle of rear-mounted horizontal tail control surface of helicopter
Technical Field
The invention relates to the field of helicopter flight control, in particular to a design method for controlling a rear-mounted horizontal tail control surface deflection angle of a helicopter.
Background
The rear-mounted wide horizontal tail layout is beneficial to increasing the longitudinal stability of the helicopter, but the interference effect of rotor wake on the horizontal tail changes along with the change of the flying speed. When the helicopter flies at a low speed, the downward rotor wake impacts the horizontal tail, so that the horizontal tail generates a strong downward force, and the helicopter is raised. Along with the increase of the flying speed, the rotor wing wake flow moves upwards, the interference of the rotor wing wake flow to the horizontal tail is gradually reduced, the upward lift force of the horizontal tail is gradually recovered, and the helicopter is raised. The sudden lowering and raising of the head of the helicopter can cause the visual observation difficulty of a pilot, the flight risk is increased, and the comfort level is limited.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides a design method for controlling the deflection angle of a rear-mounted horizontal tail control surface of a helicopter, improves the design efficiency, and avoids the problems of repeated design, influence on the development progress and the like caused by solving the problems in the flight test process after the helicopter is developed.
The purpose of the invention is realized by the following scheme:
a design method for controlling the deflection angle of a rear-mounted horizontal tail control surface of a helicopter comprises the following steps:
s1, carrying out a balancing wind tunnel test on the helicopter model without the horizontal tail to obtain the full-helicopter pitching moment and attitude angle under the condition that the horizontal tail is not installed on the helicopter at different wind speeds;
and S2, adding a horizontal tail to the helicopter model in the step S1, adjusting the deflection angle of the horizontal tail, and performing a balancing wind tunnel test on the helicopter model added with the horizontal tail.
Further, in step S1, the method includes the sub-steps of:
s11, adjusting the wind speed of the wind tunnel to a given wind speed;
s12, measuring the resistance of the fuselage;
s13, adjusting the shaft inclination angle, the total distance and the cyclic displacement of the rotor: the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero, and the forward horizontal force of the rotor wing is equal to the resistance of the helicopter body;
s14, when the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero; if the forward horizontal force of the rotor is not equal to the resistance of the fuselage, the steps S12 and S13 are continued.
Further, S15, repeating the steps S11, S12, S13 and S14 at each wind speed, the trim operation is completed when the lift force of the rotor is equal to the helicopter weight, the pitch moment and roll moment of the rotor are zero, and the forward horizontal force of the rotor is equal to the drag force of the fuselage;
summarizing the pitching moment and the pitching attitude angle of the helicopter model without the horizontal tail under different wind speeds given by the steps of S11-S15.
Further, in step S2, the method includes the sub-steps of:
s21, adjusting the wind speed of the wind tunnel to a given wind speed;
s22, adjusting the shaft inclination angle to make the inclination angle equal to the pitch attitude angle at the corresponding wind speed obtained in the step S1;
s23, adjusting the total pitch and the periodic pitch of the rotor wing to enable the lift force of the rotor wing to be equal to the gravity of the helicopter and the pitching moment and the rolling moment of the rotor wing to be zero;
s24, adjusting the horizontal tail deflection angle within the range of-40 ︒ -40 ︒, and recording the pitching moment of the fuselage under each horizontal tail deflection angle within a set range at intervals;
further, after step S24, the method includes the steps of:
and S25, repeating the steps S21, S22, S23 and S24 at each wind speed, and obtaining a horizontal tail deviation angle of which the pitching moment of the helicopter body is zero at the current wind speed, namely the horizontal tail deviation angle required by balancing the pitching moment of the helicopter at the current wind speed.
Further, in step S24, the set range is 2 °.
The beneficial effects of the invention include:
(1) the rear wide horizontal tail is designed into the deflection angle adjustable control surface, the deflection angle of the horizontal tail is changed along with the change of the flying speed, the problem that the flying attitude changes suddenly along with the change of the flying speed can be solved, and the core for solving the problems is how to provide the deflection angle of the control surface under different wind speeds. In the embodiment of the invention, the method for acquiring the rear-mounted horizontal tail control surface deflection angle of the helicopter at different flight speeds by using the wind tunnel test is provided, the design efficiency can be improved, and the problems that the problems are solved in the flight test process after the development of the helicopter, the development progress is influenced and the like due to repeated design are avoided.
(2) The embodiment of the invention determines the pitching attitude of the helicopter without the horizontal tail in advance, and the pitching attitude of the helicopter at each wind speed is mainly determined by the resistance of the helicopter body. If the resistance of the fuselage is large at high wind speeds, the helicopter needs to be tilted forward so that the forward component force generated by the pulling force of the rotor wing balances the resistance of the fuselage. Therefore, the helicopter trim wind tunnel test without the horizontal tail is firstly carried out, the attitude angle of the helicopter at each wind speed is determined, the simultaneous change of the attitude angle and the horizontal tail deflection angle in the second part is avoided, and the number of test points is reduced.
(3) According to the embodiment of the invention, the proper horizontal tail deflection angle at each speed is determined according to a wind tunnel test, a series of fuselage pitching moment measurements of the horizontal tail deflection angle are carried out on the basis of the obtained attitude angle of the helicopter at each wind speed, and the horizontal tail deflection angle of which the fuselage pitching moment is zero at the current wind speed is obtained, namely the horizontal tail deflection angle required for balancing the pitching moment of the helicopter at the current wind speed.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a flow chart of the method steps of the present invention.
Detailed Description
All features disclosed in all embodiments in this specification, or all methods or process steps implicitly disclosed, may be combined and/or expanded, or substituted, in any way, except for mutually exclusive features and/or steps.
As shown in fig. 1, a design method for controlling the deflection angle of a rear-mounted horizontal tail control surface of a helicopter comprises the following steps:
s1, carrying out a balancing wind tunnel test on the helicopter model without the horizontal tail to obtain the full-helicopter pitching moment and attitude angle under the condition that the horizontal tail is not installed on the helicopter at different wind speeds;
and S2, adding a horizontal tail to the helicopter model in the step S1, adjusting the deflection angle of the horizontal tail, and performing a balancing wind tunnel test on the helicopter model added with the horizontal tail.
In an alternative embodiment, in step S1, the method includes the sub-steps of:
s11, adjusting the wind speed of the wind tunnel to a given wind speed;
s12, measuring the resistance of the fuselage;
s13, adjusting the shaft inclination angle, the total distance and the cyclic displacement of the rotor: the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero, and the forward horizontal force of the rotor wing is equal to the resistance of the helicopter body;
s14, when the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero; if the forward horizontal force of the rotor is not equal to the resistance of the fuselage, the steps S12 and S13 are continued.
In an alternative embodiment, S15, repeating the steps S11, S12, S13 and S14 at each wind speed, the trim operation is completed when the lift force of the rotor is equal to the helicopter weight, the rotor pitch and roll moments are zero, and the forward horizontal force of the rotor is equal to the fuselage drag force;
summarizing the pitching moment and the pitching attitude angle of the helicopter model without the horizontal tail under different wind speeds given by the steps of S11-S15.
In an alternative embodiment, in step S2, the method includes the sub-steps of:
s21, adjusting the wind speed of the wind tunnel to a given wind speed;
s22, adjusting the shaft inclination angle to make the inclination angle equal to the pitch attitude angle at the corresponding wind speed obtained in the step S1;
s23, adjusting the total pitch and the periodic pitch of the rotor wing to enable the lift force of the rotor wing to be equal to the gravity of the helicopter and the pitching moment and the rolling moment of the rotor wing to be zero;
s24, adjusting the horizontal tail deflection angle within the range of-40 ︒ -40 ︒, and recording the pitching moment of the fuselage under each horizontal tail deflection angle within a set range at intervals;
in an alternative embodiment, after step S24, the method includes the steps of:
and S25, repeating the steps S21, S22, S23 and S24 at each wind speed, and obtaining a horizontal tail deviation angle of which the pitching moment of the helicopter body is zero at the current wind speed, namely the horizontal tail deviation angle required by balancing the pitching moment of the helicopter at the current wind speed.
In an alternative embodiment, in step S24, the set range is 2 °.
The parts not involved in the present invention are the same as or can be implemented using the prior art.
The above-described embodiment is only one embodiment of the present invention, and it will be apparent to those skilled in the art that various modifications and variations can be easily made based on the application and principle of the present invention disclosed in the present application, and the present invention is not limited to the method described in the above-described embodiment of the present invention, so that the above-described embodiment is only preferred, and not restrictive.
Other embodiments than the above examples may be devised by those skilled in the art based on the foregoing disclosure, or by adapting and using knowledge or techniques of the relevant art, and features of various embodiments may be interchanged or substituted and such modifications and variations that may be made by those skilled in the art without departing from the spirit and scope of the present invention are intended to be within the scope of the following claims.

Claims (2)

1. A design method for controlling the deflection angle of a rear-mounted horizontal tail control surface of a helicopter is characterized by comprising the following steps:
s1, carrying out a balancing wind tunnel test on the helicopter model without the horizontal tail to obtain the full-helicopter pitching moment and attitude angle under the condition that the horizontal tail is not installed on the helicopter at different wind speeds;
in step S1, the method includes the sub-steps of:
s11, adjusting the wind speed of the wind tunnel to a given wind speed;
s12, measuring the resistance of the fuselage;
s13, adjusting the shaft inclination angle, the total distance and the cyclic displacement of the rotor: the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero, and the forward horizontal force of the rotor wing is equal to the resistance of the helicopter body;
s14, when the lift force of the rotor wing is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor wing are zero; if the forward horizontal force of the rotor is not equal to the resistance of the fuselage, the steps S12 and S13 are continued;
s15, repeating the steps S11, S12, S13 and S14 at each wind speed, and finishing the balancing operation when the lift force of the rotor is equal to the gravity of the helicopter, the pitching moment and the rolling moment of the rotor are zero and the forward horizontal force of the rotor is equal to the resistance of the airframe;
summarizing the pitching moment and the pitching attitude angle of the helicopter model without the horizontal tail under different wind speeds given in the steps of S11-S15;
s2, a horizontal tail is additionally arranged on the helicopter model in the step S1, the deflection angle of the horizontal tail can be adjusted, and a balancing wind tunnel test is carried out on the helicopter model additionally provided with the horizontal tail;
in step S2, the method includes the sub-steps of:
s21, adjusting the wind speed of the wind tunnel to a given wind speed;
s22, adjusting the shaft inclination angle to make the inclination angle equal to the pitch attitude angle at the corresponding wind speed obtained in the step S1;
s23, adjusting the total pitch and the periodic pitch of the rotor wing to enable the lift force of the rotor wing to be equal to the gravity of the helicopter and the pitching moment and the rolling moment of the rotor wing to be zero;
s24, adjusting the horizontal tail deflection angle within the range of-40 ︒ -40 ︒, and recording the pitching moment of the fuselage under each horizontal tail deflection angle within a set range at intervals;
after step S24, the method includes the steps of:
and S25, repeating the steps S21, S22, S23 and S24 at each wind speed, and obtaining a horizontal tail deviation angle of which the pitching moment of the helicopter body is zero at the current wind speed, namely the horizontal tail deviation angle required by balancing the pitching moment of the helicopter at the current wind speed.
2. The method for designing a helicopter post-mounted rudder surface deflection angle control according to claim 1, wherein in step S24, the setting range is 2 °.
CN202111337930.2A 2021-11-12 2021-11-12 Design method for controlling deflection angle of rear-mounted horizontal tail control surface of helicopter Active CN113772115B (en)

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