KR20160016233A - System and Method for Modeling Aerodynamic Data - Google Patents

Abstract

The present invention relates to an aerodynamic modeling system and a method. According to the present invention, the system comprises an aerodynamic modeling part which receives a flight condition and a control horn displacement and then calculates force and the moment applied to a flight vehicle based on the received flight condition and the control horn displacement. According to the present invention, by obtaining aerodynamic data of the flight vehicle in real time with respect to the given flight condition and the control horn displacement, it is possible to calculate force and the moment applied to the flight vehicle more efficiently.

Description

Technical Field [0001] The present invention relates to an aerodynamic modeling system,

The present invention relates to an aerodynamic modeling system and method, and more particularly, to an aerodynamic modeling system and method that can calculate aerodynamic data according to a given flying condition and a steering surface displacement to obtain force and moment acting on a flying body in real time.

Generally, accurate aerodynamic data is needed for aircraft flight simulation, flight control logic design and automatic flight. For example, when a flight simulation of an aircraft is performed, given the flight variables or control variables as inputs, the aerodynamic database (DB) can provide forces and moments corresponding to the inputs as outputs , Force and moment can be input to the six degrees of freedom equations of motion, and the state values such as position, speed, and attitude of the vehicle can be presented as a result.

Conventionally, since the aerodynamic data corresponding to each of the variables is stored in the form of a table in the aerodynamic database (DB), the aerodynamic data table becomes large when the number of variables is large.

If the control input value is given, the corresponding aerodynamic data can be calculated by interpolating the table look-up method. If the shape of the airplane changes, new aerodynamic data is required. .

In addition, the level of the aerodynamic data table is related to the cost. If the accuracy of the aerodynamic data table is low, the cost is low. However, the aerodynamic data table must be tuned during actual flight, So that it is costly and time consuming.

Korean Patent Publication No. 1999-0086322 (published December 15, 1999)

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an aerodynamic model system and method capable of more efficiently obtaining force and moment acting on a flying body by calculating aerodynamic data of a flying object with respect to a given flying condition and a control surface displacement in real time .

Further, the present invention includes other objects that can be achieved from the construction of the present invention described later, in addition to the objects explicitly mentioned.

According to an aspect of the present invention, there is provided an aerodynamic modeling system for receiving an input of a flight condition and a steering surface displacement, And a modeling unit.

The aerodynamic modeling unit may calculate the force and moment acting on the airplane based on the shape data of the airplane and the viscous flow analysis data of the airfoil of the airplane together with the flight condition and the steering surface displacement.

The aerodynamic modeling unit applies the viscous flow analysis data of the flight condition, the control surface displacement, the shape data of the air vehicle, and the wing airfoil of the air vehicle to a predetermined aerodynamic function to determine forces and moments acting on the air vehicle Can be calculated.

The predetermined aerodynamic function may be obtained based on a lifting-line method.

The flight condition may include at least one of a speed, an angle of attack, and a side slip angle of the air vehicle.

The steering surface displacement may include at least one of an aileron displacement, an elevator displacement, and a rudder displacement.

According to an aspect of the present invention, there is provided a method of modeling an aerodynamic force, the method comprising: receiving a flight condition and a steering surface displacement; calculating a force and a moment acting on the aircraft using the received flight condition and the steering surface displacement; .

A computer-readable medium according to another embodiment of the present invention records a program for causing a computer to execute any one of the above methods.

As described above, according to the aerodynamic modeling system and method according to the embodiment of the present invention, it is possible to calculate force and moment acting on the air vehicle more efficiently by calculating the aerodynamic data of the air vehicle with respect to a given flight condition and the steering surface displacement in real time have. That is, there is an advantage that the aerodynamic data having high accuracy can be provided as compared with the conventional aerodynamic database using the table format.

Further, there is an advantage that the aerodynamic data can be calculated considering the coupling effect between the input variables.

In addition, even if the shape of the airplane changes, it is advantageous to save time and money because only the input value to the shape of the airplane needs to be changed.

On the other hand, the effects of the present invention are not limited to those described above, and other effects that can be derived from the constitution of the present invention described below are also included in the effects of the present invention.

1 is a block diagram of an aerodynamic modeling system according to an embodiment of the present invention.
2 is a flowchart illustrating an operation of an aerodynamic modeling system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

1 is a block diagram of an aerodynamic modeling system according to an embodiment of the present invention.

As shown in FIG. 1, the aerodynamic modeling system 100 may include an aerodynamic modeling unit 120 and a flight state calculating unit 140.

The aerodynamic modeling unit 120 receives the flight condition and the control surface displacement, and calculates the forces and moments acting on the aircraft using the received flight condition and the control surface displacement. Here, the flight condition includes at least one of a speed, an angle of attack, and a sideslip angle of a flying body, and the angle of attack is set such that the wing of the aircraft (wings extending to the right and left of the aircraft body) The angle is called the angle. The steering surface displacement may include at least one of an aileron displacement, an elevator displacement, and a rudder displacement.

The aerodynamic modeling unit 120 may calculate the force and moment acting on the flying body by receiving the shape data of the flying body and the viscous flow analysis data of the flying wing airfoil of the flying body together with the flight condition and the steering surface displacement.

Here, the shape data of the flying body is data representing the physical shape of the flying body. On the other hand, Wing Airfoil means a two-dimensional shape of a section of a three-dimensional wing of an air vehicle. That is, one wing can be composed of several wings having different sectional shapes in the span direction. The viscous flow analysis data of the flight wing airfoil is the viscous flow analysis data of the two-dimensional airfoil constituting the wing. If the wing uses three cross-section airfoils, it should have three viscoelastic flow analysis data. The shape data of the flying body and the wing airfoil viscous flow analysis data of the flying body can be generated in advance and stored in a storage unit (not shown).

More specifically, the aerodynamic modeling unit 120 applies the viscous flow analysis data of the flight condition, the steering surface displacement, the shape data of the flying body, and the wing airfoil of the airplane to a predetermined aerodynamic function, And can be implemented by an aerodynamic calculation program.

A predetermined aerodynamic function can be expressed as [Equation 1] below.

[Equation 1]

Here, Fx, Fy and Fz are forces in the x direction, forces in the y direction, forces in the z direction, and L, M and N are the x axis moments, y axis moments and z axis moments, respectively.

And, a predetermined aerodynamic function can be obtained based on a lifting-line method. Here, the lift line method is a suitable method to be applied in the conceptual design of a wing, assuming that the cross-sectional airfoil of the wing is thin, the Weissinger method which gives the velocity boundary condition at the control point of the 3/4 prototype, And a Phillips method using the same.

In other words, the nonlinear analysis considering the viscous effect becomes possible by using the lift and viscous drag data for the cross - sectional airfoil of the flight wing with the three - dimensional flow analysis by the lift line method. The viscous flow analysis for the airfoil can be made using XFOIL or JAVAFOIL with published code or wind tunnel test data.

The aerodynamic calculation program can be implemented as an executable file created in Fortran language. The shape data of the flight body and the viscous flow analysis data of the flight wing airfoil of the air vehicle can be implemented so as to be included in the aerodynamic calculation program in advance.

Therefore, the aerodynamic calculation program can calculate and output the force and moment in the three-axis direction acting on the air vehicle by receiving the flight condition or the steering displacement.

On the other hand, if the shape of the air vehicle is changed, the shape data of the air vehicle stored in advance in the source program of the aerodynamic calculation program can be modified, and the execution file can be re-created and applied to the aerodynamic model. Thus, even if the shape of the airplane changes, it is not necessary to newly create an aerodynamic data table, so that a new shape of the airplane can be applied more easily.

The aircraft state calculating unit 140 receives the forces and moments acting on the flying object obtained from the aerodynamic modeling unit 120, and substitutes the forces and moments of the flying body into the six-degree-of-freedom motion equation of the flying object to calculate the state The value can be calculated.

As such, the aerodynamic modeling system is suitable for low-speed unmanned aerial vehicles, because low-cost unmanned aerial vehicles can not afford to spend a lot of money to build aerodynamic data databases. However, the aerodynamic modeling system according to the embodiment of the present invention makes a scheme capable of calculating aerodynamic data in a very short period of time, and a GPU (Graphic Processor Unit) And can exchange data with the central processing unit (CPU) mounted on the aircraft, and can provide aerodynamic data with much higher accuracy than DATCOM.

Hereinafter, a process of modeling aerodynamic data according to an embodiment of the present invention will be described.

2 is a flowchart illustrating an operation of an aerodynamic modeling system according to an embodiment of the present invention.

As shown in FIG. 2, the aerodynamic modeling unit 120 can receive the flight condition and the steering surface displacement (S300). Here, the flight condition includes at least one of a speed, an angle of attack, and a sideslip angle of a flying body, and the angle of attack is set such that the wing of the aircraft (wings extending to the right and left of the aircraft body) The angle is called the angle. The steering surface displacement may include at least one of an aileron displacement, an elevator displacement, and a rudder displacement.

At this time, the shape data of the air vehicle and the viscous flow analysis data of the wing airfoil can be input together with the flight condition and the steering surface displacement.

Then, the aerodynamic modeling unit 120 may calculate the forces and moments acting on the air vehicle using the inputted flight condition and the steering surface displacement (S310).

The aerodynamic modeling unit 120 may calculate the force and moment acting on the air vehicle by applying the flight condition, the control surface displacement, the shape data of the air vehicle, and the viscous flow analysis data of the flying wing airfoil of the air vehicle to a predetermined aerodynamic function. , And can be implemented by the aerodynamic force calculation program expressed by Equation (1).

Next, the force and moment acting on the flying body are input, and the state values such as the position, speed, posture, and posture differential value of the flying body can be calculated by substituting it into the six degrees of freedom motion equation of the flying body.

Embodiments of the present invention include a computer-readable medium having program instructions for performing various computer-implemented operations. The medium records a program for executing the aerodynamic modeling method described above. The medium may include program instructions, data files, data structures, etc., alone or in combination. Examples of such media include magnetic media such as hard disks, floppy disks and magnetic tape, optical recording media such as CD and DVD, programmed instructions such as floptical disk and magneto-optical media, ROM, RAM, And a hardware device configured to store and execute the program. Or such medium may be a transmission medium, such as optical or metal lines, waveguides, etc., including a carrier wave that transmits a signal specifying a program command, data structure, or the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

100: Aerodynamic modeling system
120: aerodynamic modeling unit
140: flight status calculation unit

Claims (13)

An aerodynamic modeling unit for inputting the flight condition and the steering surface displacement and calculating a force and a moment acting on the air vehicle using the inputted flying condition and the steering surface displacement,
The aerodynamic modeling system comprising: The method of claim 1,
The aerodynamic modeling unit,
Wherein the shape data of the air vehicle and the viscous flow analysis data of a wing airfoil of the air vehicle are input together with the flight condition and the steering surface displacement to calculate forces and moments acting on the air vehicle. 3. The method of claim 2,
The aerodynamic modeling unit,
An aerodynamic modeling system for calculating force and moment acting on the air vehicle by applying the flight condition, the steering surface displacement, the shape data of the air vehicle, and the viscous flow analysis data of the air vehicle wing airfoil to a predetermined aerodynamic function, . 4. The method of claim 3,
Wherein the predetermined aerodynamic function is obtained on the basis of a lifting-line method. The method of claim 1,
The flight condition may include:
An aerodynamic modeling system comprising at least one of a speed, an angle of attack and a side slip angle of the air vehicle. The method of claim 1,
The steering surface displacement,
An aerodynamic modeling system comprising at least one of an aileron displacement, an elevator displacement, and a rudder displacement. Receiving the flight condition and the steering surface displacement, and
Calculating a force and a moment acting on the air vehicle using the inputted flight condition and the steering surface displacement,
Gt; a < / RTI > aerodynamic modeling method. 8. The method of claim 7,
Wherein the step of calculating force and moment acting on the flying object using the input flying condition and the steering surface displacement includes:
The aerodynamic modeling method is performed by calculating shape data of the air vehicle and viscous flow analysis data of a wing airfoil of the air vehicle along with the flight condition and the steering surface displacement and calculating force and moment acting on the air vehicle . 9. The method of claim 8,
Wherein the force and moment acting on the air vehicle are calculated by applying the flight condition, the control surface displacement, the shape data of the air vehicle, and the viscous flow analysis data of the airfoil to a predetermined air force function. The method of claim 9,
Wherein the predetermined aerodynamic function is obtained on the basis of a lifting-line method. The method of claim 1,
The flight condition may include:
And at least one of a speed, an angle of attack, and a side slip angle of the air vehicle. 8. The method of claim 7,
The steering surface displacement,
An aileron displacement, an elevator displacement, and a rudder displacement. A computer-readable recording medium storing a program for causing a computer to execute the method according to any one of claims 7 to 12.

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