KR101472387B1 - The simulation system of high altitude-low opening skydiving from the helicopter and controlling method for the same - Google Patents

Abstract

The present invention relates to a helicopter rotor modeling module for simulating a rotor blade of a helicopter using a VBM technique based on a feather element method for modeling a rotor of a helicopter; The helicopter / dumbbell interference analysis module analyzes the dropping drag force by the falling posture acting on the helicopter and the falling dropper, calculates the result, and analyzes the drag force modeling of the dropper on the interference of the dropper and the helicopter fuselage and the forward direction of the aircraft A fourth step of interference analysis of the interference signal; In the fourth step, the fall trajectory modeling module analyzes the fall drag coefficient calculated by the helicopter / dropper interference analysis module and the interference analysis result between the body / faller into the fall dynamics model to model the fall trajectory A helicopter high-drop simulation system and a control method thereof.
The present invention as described above performs a helicopter high-drop simulation by performing a helicopter integration analysis tool (HOST), a computational fluid dynamics (CFD) tool, a dropper human body modeling, a VBM model for rotor modeling, , The complex motion of the helicopter, the surrounding flow field, and the fall trajectory analysis can be easily handled. Therefore, the change of various characteristics of the helicopter due to the high-strength drop can be clearly understood and reflected in the production of the helicopter, There is an effect that can be done.

Description

TECHNICAL FIELD [0001] The present invention relates to a helicopter high-drop descent simulation system using a numerical technique, and a control method thereof. [0002]

The present invention relates to a helicopter high-drop simulation system and its control method using a numerical technique, and more particularly to a helicopter integration analysis tool (HOST), a computational fluid dynamics (CFD) tool, a dropper human modeling, a VBM model for rotor modeling, The present invention relates to a helicopter high-drop simulation system and a control method thereof using a numerical method that can easily secure the design stability of a helicopter by performing a dynamics simulation for analysis.

Generally, a helicopter is an aircraft that generates lift and propulsive force generated by rotating a rotating blade called a rotor blade, which generates a lift, and is capable of vertical takeoff and landing and air stopping, , And can make a lurch. The design of the rotor blades of the helicopter as described above can be applied to a variety of design fields such as vibration, dynamic stability, and handling qualities that directly affect the blade, as well as aerodynamic characteristics such as flight performance, aerodynamic load and noise A comprehensive review is needed. Especially, the above-mentioned helicopter performs various missions such as high altitude (HALO) missions, and this high drop is a mission of releasing a parachute to free fall when a falling person leaves the aircraft. The HALO technique reduces the risk of falling to enemies because of the relatively short fall time, and the risk of collision with each other is low even when a large number of people fall due to the rapid fall of the dropper when leaving the aircraft. For such a high-drop mission, the shape of the handle or foot plates is required to allow the dropper to fall, and there should be no problems with the projections of the aircraft when the aircraft leaves the aircraft. In addition, the helicopter where the main landing gear is located at the rear, the landing gear or the strut protrudes from the surface of the fuselage. Therefore, in the development process of the helicopter, it is necessary to perform preliminary evaluation through wind tunnel test or computational analysis in order to test and evaluate the mission such as the above-mentioned high-drop.

Referring to FIG. 1, a helicopter design method considering the above-described conventional high-level drop will be described. Referring to FIG. 1, a first step S100 of confirming a trajectory through a ground free fall test of a human body model;

A second step (S101) of confirming a trajectory through the free-flying collision test of the human body model after the first step (S100);

A third step (S102) of testing the high drop of the dropper during the second flight (S101);

And a fourth step (S103) of setting the maximum advancing speed through the high drop test during the forward flight of the dropper after the third step (S102) and ending the process.

 In order to design the helicopter considering the high drop, it is necessary to determine the shape of the helicopter to facilitate the high drop (such as application of a front wheel landing gear or skid type type landing gear) or in the presence of an external overhang or landing gear behind the helicopter, a number of tests and flight tests are carried out due to the risk of collision of the dropper. Therefore, in order to perform the above-mentioned conventional design method, first, a first step (S100) of confirming a locus through a ground free fall test of a human body model is performed. At this time, The drop test is performed to obtain the motion characteristics of the human body when the human body falls, so that it is possible to reduce the number of times of the human body model free fall impact test using the trajectory results. After the first step S100, a second step S101 of checking the trajectory through the free-flying collision test of the human body model is performed. In this second step S101, a human dummy model is utilized To perform a free fall impact test during flight and to reduce the number of tests during the actual dropper flight test. In addition, after the second step S101, a third step S102 of testing the high drop when the drop falls is performed. In the third step S102, the high drop of the actual drop is started from the first drop Gradually increases the forward flight speed and confirms the maximum speed at which safe high-drop is possible. After the third step (S102), a fourth step (S103) is performed in which the maximum advancing speed through the high-drop test is set during the forward flight of the dropper and then the end is terminated.

However, in the helicopter design method considering the above-described conventional high-drop, the helicopter shape for performing the high-low-drop operation is the main landing gear as shown in FIG. 2 (a) Type skid type landing gear so that when the main landing gear or the external overhangs are located behind the drop point because of the very low risk of collision with the dropper during high dropping, Since there is a need to test the possibility of high-drop-down tasks through progressive testing, there has been a problem in that a lot of test costs and risks are incurred.

Accordingly, it is an object of the present invention to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a helicopter which can cope with a motion of a complex helicopter, a peripheral flow field, The present invention provides a helicopter high-drop simulation system and a control method thereof using a numerical technique that can easily grasp a design stability of a helicopter because it can be clearly reflected on characteristics changes and reflected in the production of a helicopter.

It is another object of the present invention to provide a helicopter high-drop simulation system and its control using a numerical technique that maximizes the design quality of the helicopter because the helicopter high-drop simulation can be easily processed using numerical techniques without inputting actual personnel and equipment Method.

According to an aspect of the present invention, there is provided a helicopter forward flight condition analysis module for analyzing and outputting information on a body posture and a rotor of a helicopter using an analysis tool set under a helicopter forward flight condition for performing a high-level drop mission;

A helicopter rotor modeling module for modeling the rotor of the helicopter based on a Blade Element Theory;

A falling human body modeling module that adopts and models a human body model set for collision with a helicopter external protrusion at a moment when a falling person falls from the helicopter;

A helicopter / dropper that interprets the dropping drag force acting on the helicopter and the dropper falling down by the dropping posture, calculates the result, calculates the result of interference analysis between the dropper and the helicopter's body, An interference analysis module;

A helicopter using a numerical technique including a fall trajectory modeling module for modeling a fall trajectory by interpreting the drag force coefficient calculated by the helicopter / dropper interference analysis module and the interference analysis result between the body / A high-drop simulation system is provided.

According to another aspect of the present invention, there is provided a helicopter forward flight condition analysis module comprising: a first process of analyzing and outputting information on a posture of a helicopter and a rotor using an analysis tool set under a helicopter forward flight condition for performing a high-altitude mission;

A second process of simulating a rotor blade using a VBM (Virtual Blade Modeling) technique based on a Blade Element Theory to model a helicopter rotor during the first process;

A third step of modeling the human body modeling module by adopting a human body model set for collision with a helicopter external protrusion at a moment when a falling person falling from the helicopter falls down during the second process;

During the third process, the helicopter / dribbler interference analysis module interprets the falling drag force acting on the helicopter and the falling dribbler falling down by the falling posture, calculates the result, calculates the interference between the dribbler and the helicopter fuselage, A fourth step of interference analysis of the result of the drag analysis modeling;

In the fourth step, the fall trajectory modeling module analyzes the fall drag coefficient calculated by the helicopter / dropper interference analysis module and the interference analysis result between the body / faller into the fall dynamics model to model the fall trajectory To provide a control method of a helicopter high-drop simulation system using a numerical technique including a numerical method.

According to the present invention, a helicopter integration analysis tool (HOST), a computational fluid dynamics (CFD) tool, a dropper human body modeling, a VBM model for rotor modeling, and a kinematic modeling for trajectory analysis are performed, , It is possible to easily handle the motion of the complex helicopter, the surrounding flow field, and the fall trajectory analysis, so that it is possible to clearly understand the change of the characteristics of the helicopter according to the high-strength drop and to reflect it in the production of the helicopter. It is possible to secure the effect.

The present invention as described above can easily process the helicopter high-drop simulation work using a numerical technique without inputting actual personnel and equipment, thereby maximizing the design quality of the helicopter.

FIG. 1 is an explanatory view illustrating a helicopter design method considering a conventional high-drop. FIG.
Fig. 2 (ab) is an explanatory view for explaining an example of a helicopter shape taking into consideration a conventional high-level drop;
FIG. 3 is an explanatory view illustrating a helicopter high-drop simulation system using a numerical technique according to the present invention. FIG.
FIG. 4 is an explanatory view for explaining surface pressure and wire results on the dropper calculated by the helicopter / dropper interference analysis module according to the present invention; FIG.
FIG. 5 is a graph showing the results of computational fluid dynamics analysis of an aerodynamic force acting on a falling person, a falling drag to be received upon falling, and a descending flow of a rotor, which are calculated by the falling trajectory modeling module according to the present invention, and a force acting on the z-axis direction.
6 is a graph for predicting the trajectory by solving the equations of motion of force and air force acting on the dropper implemented by the apparatus of the present invention.
7 is a flowchart of the present invention.
8 is an explanatory view for explaining a result of modeling the trajectory prediction result implemented by the apparatus of the present invention using CATIA for checking interference between a helicopter body and a dropper.
FIG. 9 is an explanatory view for explaining the results of the 5th and 95th weight models implemented by the apparatus of the present invention; FIG.

Hereinafter, a preferred embodiment of a helicopter high-drop simulation system using a numerical technique according to the present invention will be described with reference to the accompanying drawings.

However, the present invention may be embodied in other forms without being limited to the embodiments of the helicopter high-drop simulation system using the numerical technique according to the present invention described herein. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals designate like elements throughout the specification. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. The term " comprises " And / or "comprising" does not exclude the presence or addition of one or more other elements, steps, operations, and / or elements.

Example

FIG. 3 is an explanatory view schematically illustrating an embodiment of a helicopter high-drop-down simulation system using a numerical technique according to the present invention. FIG. 4 is a graph showing a simulation result of a helicopter drop- FIG. 5 is a graph for explaining the effect of the air force on the forward direction acting on the dropper calculated by the falling trajectory modeling module according to the present invention, the drop drag to be received upon dropping, FIG. 6 is a graph showing the force acting on the dropper realized by the apparatus of the present invention and the equation of motion of the aerodynamic force FIG. 7 is a flowchart of the present invention, and FIG. 8 is a graph for predicting a trajectory of a helicopter, FIG. 9 is an explanatory view for explaining the results of the 5th and 95th weight models implemented by the apparatus of the present invention. FIG.

Referring to FIG. 3, a helicopter high-drop simulation system using a numerical technique according to an embodiment of the present invention includes:

A helicopter forward flight condition analysis module (2) for analyzing and outputting information on a body posture and a rotor of the helicopter (1) using an analysis tool set under a helicopter forward flight condition for performing a high - lowdown mission;

A helicopter rotor modeling module 3 for modeling a rotor of the helicopter 1 using a VBM (Virtual Blade Modeling) technique based on a Blade Element Theory;

A falling human body modeling module 5 for modeling a human body model 4 set for collision with a helicopter external protrusion at a moment when a falling person falls from the helicopter 1;

A helicopter (1) and a helicopter (1) for analyzing the dropping drag force acting on the dropper falling down by the falling position and calculating the result and calculating interference and interference analysis results of modeling the drag drop of the dropper with respect to the interference of the dropper and the helicopter / Collider interference analysis module (6);

A falling trajectory modeling module 7 for modeling a falling trajectory by interpreting the drag force coefficient calculated by the helicopter / dumbbell interference analysis module 6 and interference analysis results between the body and the dropper into a dropping dynamics model .

The helicopter forward flight condition analysis module 2 interprets the body posture of the helicopter and the rotor information using, for example, a HOST of Eurocopter, which is an integrated helicopter analysis tool. At this time, it is assumed that the helicopter forward flight speed for carrying out the high-altitude duties of the helicopter is about 80 kts. Forward flight speed: 80kts, Pitch attitude: 2.4deg, Rotor TPP: -3.9deg are set for the information of the posture of the helicopter and the rotor tip path plane (TPP) predicted through the HOST, for example, during forward flight of the helicopter do. Here, the actuator disk method based on the momentum theory for the downward analysis of the rotor uses a velocity profile corresponding to the induction velocity Vi, and in order to use the feather element method for accurate simulation, Use cyclic and flapping information. In this case, the expression for the cyclic motion and the flapping motion of the rotor blade can be expressed by Equation (1).

(1)

The coefficients and descriptions for the cyclic and flapping of the rotor thus calculated are as follows.

- Θ ₀ = -0.40771 deg: Collective Pitch

- Θ ₁ = about 12 deg: Blade Twist

-? _1c = 1.1623 deg: Long. Cyclic

-? _1s = -4.0955 deg: Lateral Cyclic

- β ₀ = -3.7286 deg: Coning Angle

-? _1c = -1.2634 deg: Long. Flapping

- β _1s = 0.69767 deg: Lateral Flapping

On the other hand, the helicopter rotor modeling module 3 assumes that a helicopter rotor blade has a diameter of more than 10 m and has a high aspect ratio in order to model the helicopter rotor blades. Therefore, in the analysis using computational fluid dynamics (CFD) for the above-described rotor modeling, many gratings are required, and for accuracy, ten millimeters of gratings per blade are required for generation of y + <1 level gratings. Also, the method using CFD has a disadvantage in that it requires a lot of human resources, cost, and time in performing shape modeling and analysis although it has few implementation constraints and high accuracy. In addition, in analyzing the above helicopter rotor, besides the accuracy of the analysis, the analysis time, the calculation equipment, and the convenience of modeling are also important parameters to consider. Furthermore, the Actuator Disk, which simulates a lifting surface by simply modeling a rotating object such as a rotor, a duct fan, or a propeller of the above helicopter, is called an Actuator Disk. Based on Momentum Theory, , And non-uniform modeling is performed by using a feather element method. The pressure or velocity profile is used as an input value, and a boundary condition is applied to perform aerodynamic analysis. Here, the helicopter rotor modeling module 3 described above simulates the rotor blades using, for example, Fluent's Virtual Blade Modeling (VBM) technique based on Blade Element Theory, which is one step ahead of the Actuator Disk. For example, the lattice information and analysis technique for the modeling of the helicopter uses a large density condition of -40 ° C for the conservative analysis and assumes the following.

(1) lattice information

- Rotor Disk: Structure Mesh (1 Cell HEXA Grid for VBM)

- Fuselage, Human Body: Unstructured Mesh (Tetra Grid)

- Total Mesh Size: Elements 2.4M, Node 0.43M

- Mesh Generation Tool: ICEM-CFD

(2) Analysis condition

- CFD Analysis Tool: Fluent

- Used Method: Virtual Blade Modeling (VBM), Trimmed Condition (ct = 0.005)

- Solver Setting: Compressible N-S, S-A Turb. Model, P-Base Coupled Solver

- Environmental Condition: 80kts @ 1200ft, -40 ℃

On the other hand, the dropping human body modeling module 5 sets the dropper for the high-dropping task to have a backpack of about 20 kg including the main parachute, and wear the assistant parachute and the helmet. Since the simulator of the present invention simulates the collision between the dropper and the external protrusion of the helicopter at the moment of dropping, the dropping human body modeling module 5 calculates the weight Lightweight (5th Weight Model) Human body model is adopted and modeled. Here, the dropping human body modeling module 5 can not simulate the movements of the arms and legs of the dropper during the computerized analysis, and performs modeling in such a manner as to spread the arms and hold the legs, which is a general attitude at the time of dropping.

Furthermore, the helicopter / dumbbell interference analysis module 6 analyzes the dropping drag force of the dropper (or fallen object) as shown in Figs. 4 and 5. At this time, when the free fall falls, the falling speed increases gradually due to the influence of gravity. However, when the terminal speed is reached, the falling drag that no longer increases in speed acts as a reaction force.

Further, the helicopter rotor interpreted by the helicopter / dumbbell interference analysis module 6 generates and analyzes a thin disk type grid to simulate the blades using the VBM technique, and the cavitation of the helicopter cabin ) Model of the body in the form of an open door considering the effect.

5, the falling trajectory modeling module 7 calculates the falling trajectory. In this process, the falling person has a potential energy due to the forward speed of the helicopter, has gravity upon falling, The reactive force acts on the side of the dropper when dragging forward, and the falling flow of the rotor blade acts in the direction of gravity when falling.

Next, the control method of the present invention having the above-described configuration will be described.

7, in the initial state S1, the helicopter forward flight condition analysis module analyzes the helicopter's body posture and the rotor information using an analysis tool set under the helicopter forward flight condition for high- (S2) of interpolating and outputting the signal;

During the first step S2, the helicopter rotor modeling module performs a second process of modeling the rotor of the helicopter using a VBM (Virtual Blade Modeling) technique based on Blade Element Theory S3);

A third step (S4) of adopting and modeling a human body model set for collision with a helicopter external protrusion at the moment when a falling person falling down from the helicopter falls down during the second process (S3);

During the third process (S4), the helicopter / dribbler interference analysis module analyzes the falling drag force acting on the helicopter and the falling dribbler falling down by the falling posture, calculates the result, and calculates the interference between the dribbler and the helicopter, A fourth step (S5) of interference analysis of the drag analysis modeling result of the dropper;

During the fourth process (S5), the fall trajectory modeling module interprets the drag force coefficient calculated by the helicopter / dropper interference analysis module 6 and the interference analysis result between the body / faller into the fall dynamics model, And a fifth step S6 of modeling the image.

In the second step S3, the use of the blade element method information using the cyclic and flapping information of the blades is utilized for the use of the feather element method. In this case, the expression for the cyclic motion and the flapping motion of the rotor blade can be expressed by Equation (1).

In other words, when simulating a helicopter for high-altitude descent by using the system of the present invention, the helicopter forward flight condition analysis module (2) analyzes the helicopter using the analysis tool set under the helicopter forward flight condition for high- Analyzes and outputs the body posture and rotor information. During the first process, the helicopter rotor modeling module 3 simulates the rotor blades using a VBM (Virtual Blade Modeling) technique based on the Blade Element Theory to model the rotor of the helicopter. After the rotor blade is modeled by the above method, the falling human body modeling module 5 adopts and models the human body model set for collision with the external protrusion of the helicopter at the moment when the falling person falls from the helicopter. Further, after adopting the human body model as described above, the helicopter / dribbler interference analysis module 6 analyzes the drop drag by the falling posture acting on the helicopter and the dropper falling down, calculates the result, Interference analysis of the modeling result of the drag force of the dropper in relation to the interference of the helicopter fuselage and the advance direction of the aircraft is analyzed. After the above process, the drop trajectory modeling module 7 analyzes the drag force coefficient and the interference analysis result between the body and the dropper calculated by the helicopter / dropper interference analysis module 6 into the dropping dynamics model, To simulate a helicopter for high-altitude descent.

Meanwhile, as shown in FIG. 5, the helicopter high-drop simulation system 8 using the numerical method according to the present invention calculates the aerodynamic force acting on the forward direction acting on the dropper, the drop drag to be received upon dropping, The flow can be obtained through computational fluid dynamics analysis and the force acting on the x and z axis directions can be determined. Here, in the x-axis direction, the dropper has the same speed as the forward flight speed of the airplane when moving from the passenger compartment to the airplane. This force is equivalent to the dynamic pressure acting on the dropper, Due to the air resistance acting, the advancing speed of the dropper is gradually reduced. In addition, the dropper has the aerodynamic force due to the gravity and rotor descending flow in the z-axis direction, and the initial drop rate is 0 m / s. As the time passes, the drop rate increases and the drop resistance increases accordingly have. As shown in FIG. 6, the helicopter high-speed drop simulation system 8 using the numerical technique of the present invention can estimate the helicopter's high speed drop rate (50kts, 60kts, 70kts, 80kts) trajectory was obtained. When the forward flight speed was 80kts, Meanwhile, as shown in FIG. 8, the helicopter high-drop simulation system 8 using the numerical technique of the present invention obtained a result of modeling the trajectory prediction results using CATIA for checking the interference between the helicopter fuselage and the dropper . In addition, the helicopter high-drop simulation system 8 using the numerical technique of the present invention has obtained results for a 5th and 95th weight model as shown in FIG. 9, It can be seen that a light dropper is in great danger of collision.

In order to solve the problem of complex helicopter motion, peripheral flow field and drop trajectory analysis, a helicopter integrated analysis tool (HOST), a computational fluid dynamics (CFD) tool, a dropper human modeling, a VBM model for rotor modeling, Simulation of helicopter high drop is performed by performing kinetic modeling for trajectory analysis. At this time, for the simulation, there is no movement of the arms, legs, etc. of the dropper, and the jump does not jump (customer opinion). The inertia moment of the dropper is ignored because it is smaller than the drag and gravity value by the aircraft speed. Not considered. For conservative analysis, the atmospheric condition was carried out at a high density of -40 ° C, and the human body model also had a large elongation, but a light model was used. As a result, there is no risk of collision during forward flight of 60kts, It was confirmed that the gap between the landing gear and the dropper was narrow in the city, and it was confirmed that it was necessary to establish a mission procedure considering the margins by gradually starting the test from the safe 60kts in the flight test of the high- have. Furthermore, in the present invention as described above, the trajectory of the dropping person can be obtained by analyzing the static force of the dropper with respect to the high-drop duties, the external force by the air force, and the aerodynamic force coefficient. For more accurate analysis, it is necessary to consider the external force, moment and initial moment of inertia according to each position. However, before the flight test, it is necessary to identify the risk factors through computer simulation, End first).

1: Helicopter 2: Helicopter forward flight condition analysis module
3: Helicopter rotor modeling Module 4: Human body model
5: Human body modeling module 6: Helicopter / dropper interference analysis module
7: Falling trajectory modeling module 8: Helicopter high-drop simulation system

Claims (6)

A helicopter forward flight condition analysis module for analyzing and outputting the information about the body posture and the rotor of the helicopter by using an analysis tool set under the forward flight condition of the helicopter for performing the high-level drop mission;
A helicopter rotor modeling module for modeling the rotor of the helicopter based on a Blade Element Theory;
A falling human body modeling module that adopts and models a human body model set for collision with a helicopter external protrusion at a moment when a falling person falls from the helicopter;
A helicopter / dropper that interprets the dropping drag force acting on the helicopter and the dropper falling down by the dropping posture, calculates the result, calculates the result of interference analysis between the dropper and the helicopter's body, An interference analysis module;
A helicopter using a numerical technique including a fall trajectory modeling module for modeling a fall trajectory by interpreting the drag force coefficient calculated by the helicopter / dropper interference analysis module and the interference analysis result between the body / High Density Simulation System. The method according to claim 1,
Wherein the helicopter rotor modeling module simulates a rotor blade using a VBM (Virtual Blade Modeling) technique. The method according to claim 1,
The falling human body modeling module simulates a collision of a dropper in a computer analysis, and modeling the human body model in a shape in which the human body model spreads its arms and the legs assume a posture. The method according to claim 1,
The helicopter rotor interpreted by the helicopter / dropper interference analysis module generates and analyzes a thin disk type grid to simulate the blade using the VBM technique, and considering the cavitation effect of the helicopter cabin A helicopter high - drop simulation system using a numerical method characterized by modeling the fuselage in the form of an open door. A first step of analyzing and outputting the information on the body posture and the rotor of the helicopter by using an analysis tool set under the helicopter forward flight condition for performing the helicopter forward flight condition analysis module;
A second process of simulating a rotor blade using a VBM (Virtual Blade Modeling) technique based on a Blade Element Theory to model a helicopter rotor during the first process;
And a second step of selecting a model to be modeled from the human body model set in the dropping human body modeling module as to whether or not the dropper falling from the helicopter collides with the external protrusion of the helicopter during the second step, A third step of modeling whether or not the module collides with the collider and the outside protrusion of the helicopter;
During the third process, the helicopter / dribbler interference analysis module interprets the falling drag force acting on the helicopter and the falling dribbler falling down by the falling posture, calculates the result, calculates the interference between the dribbler and the helicopter fuselage, A fourth step of interference analysis of the result of the drag analysis modeling;
In the fourth step, the fall trajectory modeling module analyzes the fall drag coefficient calculated by the helicopter / dropper interference analysis module and the interference analysis result between the body / faller into the fall dynamics model to model the fall trajectory A method for controlling a helicopter high - drop simulation system using a numerical technique including. 6. The method of claim 5,
Wherein the second step further comprises a step of using a peak element method information using cyclic and flapping information of a blade for use of a feather element method.

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