KR20160051349A - Method for pressure interpolation technology of aircraft fuel tank, and recording medium storing program for executing the same, and recording medium storing program for executing the same - Google Patents

Abstract

The present invention relates to a method for internal pressure interpolation technology of an aircraft fuel tank, a recording medium storing a program to execute the same, and a computer program stored in the medium to execute the same and, more specifically, provides a method for internal pressure interpolation technology of an aircraft fuel tank, a recording medium storing a program to execute the same, and a computer program stored in the medium to execute the same. A load generated by a fluid in accordance with movement of an aircraft can be applied to various uniform or ununiform surface pressure interpolation problems by applying three-dimensional surface pressure interpolation technology based on a radial basis function, a surface pressure calculation method for a finite element, and an equivalent grid force conversion method.

Description

TECHNICAL FIELD [0001] The present invention relates to an internal pressure mapping method for an aircraft fuel tank, a recording medium storing a program for implementing the method, and a computer program stored in a medium for implementing the same. RECORDING MEDIUM STORING PROGRAM FOR EXECUTING THE SAME}

The present invention relates to an internal pressure mapping method for an aircraft fuel tank, a recording medium storing a program for implementing the method, and a computer program stored in a medium for implementing the method. More particularly, An internal pressure mapping method of an aircraft fuel tank applicable to uniform or non-uniform surface pressure mapping problems by applying three-dimensional surface pressure interpolation technique based on radiator low function, surface pressure calculation method of finite element and pressure equivalent node load conversion method A recording medium storing a program for implementing the same, and a computer program stored in a medium for implementing the same.

The fuel tank mounted on the aircraft is a complicated structure in which the external aerodynamic load due to the aircraft start, the inertial load due to the structure weight, the weight of the fuel in the tank, and the load effect due to the behavior of the fuel.

The behavior of the fuel in the tank generates hydrostatic pressure and acts on the structure in the form of uneven 3-dimensional pressure. Due to the complex tank geometry and the three-dimensional pressure profile, it was difficult to map directly to the finite element model (FEM).

The water pressure generated by the behavior of the fuel has a problem that it is difficult to map directly to the finite element model (FEM) as a nonuniform 3-dimensional pressure pattern.

Also, there is a problem that it is difficult to apply the method of mapping the pressure values directly to the nodes of all the elements of the FEM, as many analysis conditions and FEM shapes are changed.

 In the development process of moving objects such as air or water such as aircraft or ship, it is essential to map the external pressure to the FEM by the start of the object. In most cases, the number of mapping conditions is large and the design of the structure is continuously changed.

However, the use of the mapping function of a CFD program in this mapping process has a problem that a detailed finite element model, precise modeling, and a lot of calculation time are required.

In addition, the fluid-structure interface (FSI) mapping method using the CSD programs such as MSC / Nastran and ZAERO, which are mainly used for vibration mode analysis and aeroelastic analysis, is based on the number of connection points, Since the result of the load mapping depends on the stiffness difference of the structure, it is not suitable for the static displacement of external pressure.

That is, conventionally, a model suitable for each object must be created, and the models can not be used in other fields.

Korean Unexamined Patent Publication [10-2003-0009879] discloses a dynamic load analysis method for modeling an aircraft.

Korean Patent Publication [10-2003-0009879] (Published on February 05, 2003)

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a three-dimensional pressure interpolation method based on a radiator basis function, A method of calculating the surface pressure of a finite element and a method of pressure equalization (Equivalent Grid Force) are applied to develop a general purpose code to develop an internal pressure mapping method of an aircraft fuel tank which can uniformly or nonuniform pressure. .

According to an aspect of the present invention, there is provided an internal pressure mapping method for an aircraft fuel tank, including the steps of: A fluid pressure calculation step (S10) for calculating a fluid pressure, which is a load generated by the fluid at the reference point in the aircraft fuel tank, based on the reference point and the fuel height information from the reference point and using the hydrostatic theory, ); An analysis condition input step (S20) for receiving an analysis condition including a finite element, a control condition, a fluid pressure value of the fluid pressure calculation step (S10), and position information corresponding to the fluid pressure; A pressure interpolation step (S30) of interpolating pressure using a three-dimensional pressure interpolation method based on a radial basis function based on the information input in the analysis condition input step (S20); A surface pressure calculation step (S40) of calculating a surface pressure of the finite element by using a finite element analysis method based on the interpolated pressure in the pressure interpolation step (S30); And a pressure mapping step (S50) of mapping a uniform or non-uniform pressure using a pressure-equivalent node force transformation method based on the surface pressure calculated in the surface pressure calculation step (S40) .

In addition, the analysis condition input step S20 includes an analysis condition storage step S21 for storing the control condition list in the form of a list by receiving the name of the control condition file; An analysis condition calling step (S22) for sequentially calling the stored control condition list in the analysis condition storage step (S21); And an input file calling step (S23) for sequentially calling a control condition file of the control condition list called in the interpretation condition calling step (S22); And a control unit.

In the analysis condition storage step S21, the control condition list includes a finite element file name (FEmodel), an analysis number (LC), a fluid pressure value location information storage file name (CPS_FileName), a fluid pressure value information storage file name (PRE_FileName) Ratio (Scale Factor).

The pressure interpolation step S30 receives the finite element, determines the triangular element CTRIA3, the square element CQUAD4, and the grid GRID, and sequentially stores the information in the matrix variables A A finite element classification step S31; An algorithm for finding a center point and a normal vector according to a triangle element or a square element is applied to the matrix parameters A stored in the finite element classification step S31 and the calculated result is used as matrix variables B) in a step S32. A position information processing step (S33) of calling the fluid pressure value position information and storing the fluid pressure value position information in a matrix variable (C); A pressure value processing step (S34) of calling the fluid pressure value information and storing the information in a matrix variable (D); (A, B, C and D), and based on the fluid pressure value position information and the fluid pressure value information, the fluid pressure value at the center point of all the elements to be interpolated is calculated as the emitter low function Radial Basis Function) to distinguish whether the element is a triangle or a rectangle, and interpolating the element using information corresponding to the triangle element and the square element (S35).

The surface pressure calculation step S40 is characterized in that the fluid pressure value interpolated in the pressure interpolation step S30 is read and stored in a pressure load input type format of Nastran.

In the pressure mapping step S50, the fluid pressure value interpolated in the pressure interpolation step S30 is read and stored in the form of a vertex load input type of NSTRAN, and a fluid pressure value mapped to each element Is applied sequentially by applying the Equivalent Grid Force calculation algorithm, and the interpolation ratio is applied.

If there are various mapping conditions in one control condition file, the internal pressure mapping method of the aircraft fuel tank repeatedly executes the number of mapping conditions from S20 to S50, and the result is accumulated And stores it.

In addition, the internal pressure mapping method of the aircraft fuel tank is characterized in that when there are several cases of the control condition file, the number of control condition files is repeatedly executed from S20 to S50.

According to an embodiment of the present invention, there is provided a computer-readable recording medium on which a program for implementing an internal pressure mapping method of the aircraft fuel tank is stored.

According to an embodiment of the present invention, a program stored in a computer-readable recording medium is provided for implementing the internal pressure mapping method of the aircraft fuel tank.

According to an internal pressure mapping method of an aircraft fuel tank according to an embodiment of the present invention, a fluid pressure, which is a load generated by a fluid in accordance with an aircraft start, is calculated, and four main factors (finite element, fluid pressure value, fluid pressure Value position information, and control condition), it is possible to obtain uniform or non-uniform surface pressure mapping problems by applying three-dimensional surface pressure interpolation technique based on radiator low function, surface pressure calculation method of finite element and pressure equivalent node load conversion method There is an effect that can be applied to.

In addition, there is an effect that it is possible to solve the problem in which the object to which the pressure is to be mapped is a complex three-dimensional shape, which was not possible to directly imagine.

In addition, using the methods provided by commercial tools or using in-house code, it is possible to solve problems that were impossible to imagine.

In addition, it is possible to solve the problem that the number of analysis conditions is large and it is difficult to cope with frequent shape changes.

In addition, there is an effect that it is possible to solve the problem that different procedures, input / output formats and formats can not be commonly used for each type of event. In other words, conventionally, a model suitable for an object has to be created, and the models can not be used in other fields. However, the present invention is applicable to all fields.

1 is a flowchart of an internal pressure mapping method of an aircraft fuel tank according to an embodiment of the present invention;
2 is a flowchart according to an embodiment of the analysis condition input step of FIG.
Figure 3 is a flow diagram according to one embodiment of the pressure interpolation step of Figure 1;
4 is a flow chart showing a loop according to the number of mapping conditions of FIG.
Figure 5 is a flow diagram showing a loop according to the number of control condition files of Figure 1;

Hereinafter, the present invention will be described in more detail with reference to the drawings. The following drawings are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the following drawings, but may be embodied in other forms. In addition, like reference numerals designate like elements throughout the specification. It is to be noted that the same elements among the drawings are denoted by the same reference numerals whenever possible. Further, it is to be understood that, unless otherwise defined, technical terms and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

FIG. 1 is a flowchart of an internal pressure mapping method of an aircraft fuel tank according to an embodiment of the present invention, FIG. 2 is a flow chart according to an embodiment of an analysis condition input step of FIG. 1, FIG. 4 is a flowchart showing a loop according to the number of mapping conditions in FIG. 1, and FIG. 5 is a flowchart showing a loop according to the number of control condition files in FIG.

Prior to the description, the terms used in this specification (and claims) will be briefly described.

The loads applied to the aircraft include external aerodynamic loads due to aircraft start-up, inertial loads due to the weight of the structure, loads due to fluid (fuel) depending on the fuel weight in the tank and aircraft start-up.

The aerodynamic load refers to the external force applied to the aircraft, that is, the force (load) generated by the air, and the aerodynamic load (external aerodynamic load) can be obtained using the commercial code for the aircraft starting condition.

The inertial load can be obtained from the reference weight value of the design data by the inertial load by the structure weight of the nodal form.

Design or analysis can be done using computer software tools (such as finite element analysis) in order to design or analyze using the force calculated by the fluid generated by the aircraft.

'Finite element analysis' (FEA) is a computer simulation technique used in engineering analysis. It is common to use a numerical technique called a finite element method (FEM) and to perform mesh generation.

'Mapping' refers to the transfer of the load created by the mesh generation to the software tool.

As shown in FIG. 1, an internal pressure mapping method for an aircraft fuel tank according to an embodiment of the present invention includes a program type executed by an arithmetic processing means including a computer, A fluid pressure calculation step S10, an analysis condition input step S20, a pressure interpolation step S30, a surface pressure calculation step S40, and a pressure mapping step S50.

The fluid pressure calculation step S10 is a step of calculating a fluid pressure based on the control points or survey points CPS and the fuel height information from the reference point, Lt; RTI ID = 0.0 > pressure). ≪ / RTI >

The input value may be the reference point and the height of the fluid (maximum length) with respect to the reference point. At this time, the height of the fluid may be the maximum internal straight line length in six directions (front, back, left, right, and top and bottom) of the fuel tank.

The reference point CPS is also referred to as a point of action and refers to the position of necessary parts (geometrically changing parts, etc.) in order to calculate the pressure applied to the entire area, and the pressure at the point of action can be known by applying the hydrostatic pressure theory .

The pressure at a specific position (action point) generated by the fuel behavior in the aircraft fuel tank is expressed by the following equation

(Where pc is the pressure at a specific location (point of action), po is the pressure acting on the fuel surface, ρ is the fuel density, aH is the local acceleration, and H is the height of the fluid.

(Which is the same as the fuel pressure) and the hydrostatic pressure.

In general, the shape of the fuel tank is complicated and it is not effective to calculate and apply the pressure at all the positions coinciding with the FEM. Therefore, it is possible to simplify the shape by defining specific positions for calculation of the internal pressure, It is defined as CPS (control points, or survey points).

The local acceleration that affects the fluid pressure value is calculated using the start variables and distance in the aircraft's C.G. (Center of Gravity)

(Where a _C is the acceleration at point C, a _cg is the acceleration in the aircraft CG, ω is the angular velocity of the aircraft rotation, and R _C is the distance from the aircraft CG to the local position).

Can be calculated as follows.

Since the fuel tank is designed to be a FEM model, it is possible to map the internal pressure of the aircraft fuel tank to the FEM model based on the pressure at the point of action.

You need to calculate the fluid pressure across the whole range, because fluid pressure works the same in three-dimensional space, so you can use the hydrostatic theory to calculate the pressure at a specific location in the tank.

The analysis condition input step S20 receives the analysis conditions including the finite element, the control condition, the fluid pressure value of the fluid pressure calculation step S10, and the position information corresponding to the fluid pressure. Here, the control condition refers to a process for automating a situation where various operations are simultaneously performed. That is, when four main factors (finite element, fluid pressure value, fluid pressure value position information, control condition) are inputted, it is possible to solve the complicated pressure mapping problem. In this case, the finite element and the fluid pressure value can be inputted in the source form, the fluid pressure value position information can be inputted in the target form, and the control condition can be inputted as the control form .

At this time, the analysis condition input step S20 may include an analysis condition storage step S21, an analysis condition calling step S22, and an input file calling step S23.

The analysis condition storage step S21 receives the name of the control condition file and stores the control condition list in the form of a list. Here, the control condition file refers to a batch file for automating such operations in the case where various operations occur at the same time.

That is, the name of the control condition file stored in the folder where the control condition file (control file) is stored can be stored as a list type file. This list of stored control conditions (files) can be as many as several thousand.

The control condition list includes a finite element file name (FEmodel), an analysis number (LC), a fluid pressure value location information storage file name (CPS_FileName), a fluid pressure value information storage file name (PRE_FileName), and an interpolation ratio (SF: ScaleFactor) .

The analysis condition calling step S22 sequentially calls the stored control condition list in the analysis condition storage step S21. That is, when a list of control conditions of one of the control condition lists is called and a series of processes for one control condition list is completed, another list of control conditions can be called. In this manner, A loop can be executed to perform a series of processes.

For example, if the object model to be interpolated is composed of one (interpreted as Single), it can be adjusted by the number of rows in the condition file. It is also possible to configure each case input branch execution mode.

The input file calling step (S23) sequentially calls the control condition file of the control condition list called in the interpretation condition calling step (S22). That is, when the first control condition file of the list of called control condition is called and the series of processing of the called control condition file is completed, the next control condition file can be called. In this manner, To execute a series of processing steps.

The pressure interpolation step S30 interpolates the pressure using a three-dimensional pressure interpolation method based on a radial basis function based on the information input in the analysis condition input step S20.

The Radial Basis Function (RBF) is a mathematical theory that performs interpolation using a reference value that knows the value at a specific position within a boundary point on a three-dimensional space. The radial basis function is a radial basis function or a radial basis function Also called.

The pressure interpolation step S30 may include a finite element classification step S31, a center point search step S32, a position information processing step S33, a pressure value processing step S34, and an element interpolation step S35 .

The finite element classification step S31 receives the finite element, identifies the triangular element CTRIA3, the rectangular element CQUAD4, and the grid GRID, and sequentially stores the information in the matrix variables A.

For example, the finite element file FEmodel is received, the finite element file information is sequentially read, the triangular element CTRIA3, the rectangular element CQUAD4, and the grid GRID are discriminated, and each information is stored in the matrix variable CQUAD4 , CTRIA3, GRID).

The center point searching step S32 receives the matrix variables A stored in the finite element classifying step S31 and applies an algorithm for finding a center point and a normal vector according to a triangle element or a square element, And sequentially stores the result in the matrix variables (B).

In other words, using a plane equation, normal vectors can be found for the surface of the finite element model.

For example, the matrix variables (CQUAD4, CTRIA3, and GRID) are received, and the center point and the normal vector according to the triangular element CTRIA3 and the square element CQUAD4 are calculated, and the matrix variables C4NV, C3NV, C4CEN, Can be stored. At this time, it is preferable to sequentially execute from the first row.

In the position information processing step S33, the file storing the fluid pressure value position information is called and stored in the matrix variable C.

Here, the fluid pressure value position information can use known fluid pressure value position information.

The known fluid pressure value may be large or small for the mesh of the object to be raised. At this time, the object to be raised is to be converted to match the object to which the object is to be raised, which is the fluid pressure value of the object to be raised. That is, it is the joint value of the original information.

For example, the fluid pressure value position information file may be input and stored in a matrix variable (CPS). At this time, it is preferable to sequentially execute from the first row.

The pressure value processing step S34 calls the fluid pressure value information storage file and stores it in the matrix variable D. [

For example, a fluid pressure information file can be input and stored in a matrix variable (PRESS). At this time, it is preferable to sequentially execute from the first row.

The element interpolation step S35 receives the values of the generated matrix variables A, B, C, and D, and calculates a fluid pressure value at the center point of all the elements to be interpolated based on the position information and the fluid pressure value information, By applying the Radial Basis Function, we distinguish whether the element is a triangle or a rectangle, and interpolate using information corresponding to the triangle element and the rectangle element.

For example, based on the values stored in the matrix variables (CQUDA4, CTRIA3, C4CEN, C3CEN, CPS, PRESS) and based on the fluid pressure value information and fluid pressure value position information of the input element, Can be stored in the matrix variables (C4PRE, C3PRE) according to the square element (CQUAD4). At this time, it is preferable to sequentially execute from the first row.

If structural nodes X, aerodynamic nodes Y, and displacement values (= fluid pressure values) of structural nodes located in space are defined as u,

The fluid pressure values between given boundary nodes are defined as the interpolation function S, which represents the fluid pressure value at any point in the region, and can be expressed as:

Where X _j is the boundary nodes that know the fluid pressure value, p (X) is the third order polynomial to improve the accuracy of the three-dimensional correction, ∥ is the Euclidean length function.)

In the case of 3D, if the coordinates of the nodal points are expressed as x, y, z, the Euclidean distance can be expressed as the distance between the nodal points as follows.

When using Gaussian function with radiator low function (RBF)

, The polynomial equation is not defined. In order to obtain the coefficient, the additional condition that the order of the polynomial q is equal to or smaller than the polynomial p (Othogonal condition)

Should be used.

Therefore, using the above equations,

As shown in Fig.

Here, A represents an interpolation matrix,

As shown in Fig.

Further, in the case of the three-dimensional case, [P], {u}, {alpha}, and {c}. {0}. The matrix [0]

As shown in Fig.

를 만족하는 보간값 x_j를 구하기 위해

를 적용하여 3차원에서 보정 다항식이 표함된 경우는 다음식Known Constraints

To obtain an interpolation value x _j that satisfies

And the correction polynomial is expressed in three dimensions by applying the following equation

And interpolation function to obtain each interpolation value is defined using the following equation

Respectively.

The surface pressure calculation step S40 calculates the surface pressure of the finite element using the finite element method based on the pressure interpolated in the pressure interpolation step S30.

At this time, the surface pressure calculation step (S40)

The fluid pressure value interpolated in the pressure interpolation step (S30) is read and stored as a pressure load input type format of NASSTRAN. Here, NASTRAN (NASA Structural Analysis Computer System) is a structural analysis computer system developed by National Aeronautics and Space Administration (NASA). It is used to automate numerical analysis and simulation for structural design of aircraft, etc. Computer Aided Engineering (CAE) tool.

For example, the matrix parameters (C4PRE, C3PRE) stored in the pressure interpolation step (S30) may be input. At this time, the analysis number (LC) can be further input. Thereafter, it can be stored as a pressure load input format (**** (LC number) _PLOAD4.nap **** (LC number) _PLOAD.nap) of NASTRAN.

The pressure mapping step (S50) maps the uniform or nonuniform pressure using a pressure-equivalent node force transformation method based on the surface pressure calculated in the surface pressure calculation step (S40).

At this time, the pressure mapping step (S50) reads the fluid pressure value interpolated in the pressure interpolation step (S30) and stores it in a format of a vertex load input type of NSTRAN, And then the interpolation ratio is applied to the calculation result of the equivalent gravity load calculation algorithm.

In other words, the pressure acting on the surface of the finite element model can be distributed by the equivalent load of each material point of the component.

For example, applying the Equivalent Grid Force calculation algorithm based on matrix variables (C4PRE, C3PRE, C4NV, C3NV, analysis number (LC) and interpolation ratio (SF) It can be saved as a load input format (**** (LC number) _FLOAD4.nap).

The information transfer between the aerodynamic lattice model and the structural finite lattice model is mainly performed using the interpolation function G from the structural node points of the grid model to the aerodynamic limiting nodes,

(Where h denotes aerodynamic constraint nodes (known values) and x denotes structural finite element nodes.)

As shown in Fig.

Applying the principle of virtual work to the relationship between the aerodynamic force {F _a } obtained from the aerodynamic lattice and the equivalent load {F _s } acting on the structural lattice,

Can be obtained as follows. In order for the equation about the load acting on the structural grid to always be established for an artificial virtual displacement,

, Which can be used to determine the force (pressure) transmitted from known aerodynamic nodes to structural nodes.

To simplify this process,

Respectively. Therefore,

Can be mapped to the pressure value at any mapped structural node.

As shown in FIG. 4, when there are various mapping conditions in one control condition file, the internal pressure mapping method of an aircraft fuel tank according to an embodiment of the present invention is repeatedly executed from S20 to S50 by the number of mapping conditions , And the results are accumulated in accordance with the analysis condition (LC) number.

That is, when the finite element model is complicated, it is possible to set each model as a zone and apply it.

As shown in FIG. 5, in the method of calculating the internal pressure of the aircraft fuel tank according to the embodiment of the present invention, when there are many cases of the control condition file, the number of control condition files is repeatedly executed from S20 to S50 .

Consequently, the internal pressure mapping method of an aircraft fuel tank according to an embodiment of the present invention relates to a programming technique (matlab) capable of integrating, processing and outputting individual algorithms. In addition, it can be easily applied by applying the working point, the fluid pressure (working pressure) and the finite element model to each zone.

Although the method of calculating the internal pressure of the aircraft fuel tank according to the embodiment of the present invention has been described above, the present invention is not limited to the computer-readable recording medium storing the program for implementing the internal pressure mapping method of the aircraft fuel tank, Of course, a program stored in a computer-readable recording medium for implementing the mapping method may also be implemented.

That is, those skilled in the art will readily understand that the above-described internal pressure mapping method of an aircraft fuel tank can be provided in a recording medium readable by a computer by tangibly embodying a program of instructions for implementing the same . In other words, it can be implemented in the form of a program command that can be executed through various computer means, and can be recorded on a computer-readable recording medium. The computer-readable recording medium may include program commands, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer-readable recording medium may be those specially designed and configured for the present invention or may be those known and available to those skilled in the computer software. Examples of the computer-readable medium include magnetic media such as hard disks, floppy disks and magnetic tape, optical media such as CD-ROMs and DVDs, and optical disks such as floppy disks. Magneto-optical media and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, USB memory, and the like. The computer-readable recording medium may be a transmission medium such as a light or metal line, a wave guide, or the like, including a carrier wave for transmitting a signal designating a program command, a data structure, and 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. The hardware device may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

S10: fluid pressure calculation step
S20: input step of analysis condition
S21: Analysis condition storage step
S22: Interpreting condition call step
S23: input file calling step
S20: Pressure interpolation step
S31: Finite element classification step
S32:
S33: Position information processing step
S34: pressure value processing step
S35: Element interpolation step
S40: Surface pressure calculation step
S50: Pressure mapping phase

Claims (10)

A method of internal pressure mapping of an aircraft fuel tank comprising a program form executed by an arithmetic processing means including a computer,
A fluid pressure calculation step (S10) of calculating a fluid pressure, which is a load generated by the fluid at the reference point in the aircraft fuel tank, based on the reference point and the fuel height information from the reference point, using the hydrostatic pressure theory;
An analysis condition input step (S20) for receiving an analysis condition including a finite element, a control condition, a fluid pressure value of the fluid pressure calculation step (S10), and position information corresponding to the fluid pressure;
A pressure interpolation step (S30) of interpolating pressure using a three-dimensional pressure interpolation method based on a radial basis function based on the information input in the analysis condition input step (S20);
A surface pressure calculation step (S40) of calculating a surface pressure of the finite element by using a finite element analysis method based on the interpolated pressure in the pressure interpolation step (S30); And
A pressure mapping step (S50) of mapping a uniform or nonuniform pressure using a pressure-equivalent node force transformation method based on the surface pressure calculated in the surface pressure calculation step (S40);
Wherein the internal pressure of the fuel tank is greater than the internal pressure of the fuel tank.
The method according to claim 1,
The analysis condition input step (S20)
An interpretation condition storage step (S21) of storing a control condition list in the form of a list by receiving the name of the control condition file;
An analysis condition calling step (S22) for sequentially calling the stored control condition list in the analysis condition storage step (S21); And
An input file calling step (S23) for sequentially calling a control condition file of the control condition list called in the interpretation condition calling step (S22);
Wherein the internal pressure of the fuel tank is greater than the internal pressure of the fuel tank.
3. The method of claim 2,
In the analysis condition storage step (S21), the control condition list
(EN) An aircraft fuel tank comprising a finite element file name (FEmodel), an interpretation number (LC), a fluid pressure value location information storage file name (CPS_FileName), a fluid pressure value information storage file name (PRE_FileName) and an interpolation ratio (ScaleFactor) Internal pressure mapping method.
The method according to claim 1,
The pressure interpolation step (S30)
A finite element classifying step S31 for receiving a finite element and discriminating the triangle element CTRIA3, the rectangular element CQUAD4, and the grid GRID, and sequentially storing the information in the matrix variables A;
An algorithm for finding a center point and a normal vector according to a triangle element or a square element is applied to the matrix parameters A stored in the finite element classification step S31 and the calculated result is used as matrix variables B) in a step S32.
A position information processing step (S33) of calling the fluid pressure value position information and storing the fluid pressure value position information in a matrix variable (C);
A pressure value processing step (S34) of calling the fluid pressure value information and storing the information in a matrix variable (D); And
Based on the fluid pressure value position information and the fluid pressure value information, the fluid pressure value at the center point of all the elements to be interpolated is input to the radiator low function (Radial) (S35) for distinguishing whether the element is a triangle or a rectangle by applying the Basis Function, interpolating the information using the information corresponding to the triangle element and the rectangle element;
Wherein the internal pressure of the fuel tank is greater than the internal pressure of the fuel tank.
The method according to claim 1,
The surface pressure calculation step (S40)
Wherein the interpolated fluid pressure value in the pressure interpolation step (S30) is read and stored in a pressure load input format of Nastran.
The method according to claim 1,
The pressure mapping step (S50)
The interpolated fluid pressure value in the pressure interpolation step S30 is read and stored in a vertex load input type format of Nastran,
Wherein the fluid pressure values mapped to each element are sequentially processed by applying an Equivalent Grid Force calculation algorithm and an interpolation ratio is applied.
The method according to claim 1,
The internal pressure mapping method of the aircraft fuel tank
Wherein when there are various mapping conditions in one control condition file, the number of mapping conditions is repeatedly executed from S20 to S50, and the results are accumulated and stored in accordance with the number of the analysis condition (LC) Pressure mapping method.
The method according to claim 1,
The internal pressure mapping method of the aircraft fuel tank
Wherein the control condition file is repeatedly executed from S20 to S50 as many times as the number of control condition files.
A computer-readable recording medium storing a program for implementing an internal pressure mapping method of an aircraft fuel tank according to any one of claims 1 to 8.
A program stored in a computer-readable medium for implementing an internal pressure mapping method of an aircraft fuel tank as claimed in any one of claims 1 to 8.

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