Embodiments of the present subject matter generally relate to finite element analysis (FEA), and more particularly, to selection of an equivalent one dimension (1D) element type in a destination FEA tool corresponding to each 1D element in a source FEA tool for performing FEA.
Typically, more than one finite element analysis (FEA) tool is used in performing an analysis of a structure. For example, in structural analysis of aircraft structures, one FEA tool is used for linear analysis and another FEA tool is used for non-linear analysis. Typically, depending on size of the structure and analysis to be performed, it may take several hours to years in building a finite element model (FEM) based on the FEA tool. It may be envisioned that the redundant task of rebuilding the FEM from scratch for other FEA tools may be time consuming and typically, to overcome this, commercially available finite element translators provided by tool providers are used.
These finite element translators may accurately translate two dimension (2D) and 3D elements, loads, constraints, coordinate systems and so on in the structure. However, translating 1D elements using these finite element translators may result in errors. For example, errors include faulty translation of transverse shear stiffness, swapping cross-sectional (C/S) properties like moment of inertia about an elemental axis, failing to convert neutral axis (NA) offset with reference to a shear centre (SC), failing to select correct element type in a destination FEA tool and so on.
In one example, a source FEA tool, such as Nastran™, may define a 1D element with varying C/S area (i.e., a tapered beam) and a destination FEA tool, such as Abaquse, may not define the 1D element with varying C/S area. In such a situation, existing finite element translators may translate the tapered beam as a uniform beam. In another example, for capturing correct stiffness of a FEM, 1D elements may be modeled by considering some C/S properties of the 1D elements as zero or unrealistic. Therefore, such translations may cause non-convergence in the non-linear analysis.
A system and method for selection of an equivalent one dimension (1D) element type in a destination finite element analysis (FEA) tool for 1D elements of a source FEA tool are disclosed. According to one aspect of the present subject matter, 1D elements in a finite element model (FEM) of the source FEA tool are selected based on associated physical behavioral features. Further, shear stiffness factors associated with each selected 1D element in the FEM of the source FEA tool are extracted. Furthermore, the equivalent 1D element type is selected in a FEM of the destination FEA tool corresponding to each selected 1D element in the FEM of the source FEA tool based on the extracted shear stiffness factors. In addition, each selected 1D element in the FEM of the source FEA tool is converted to the FEM of the destination FEA tool using the selected equivalent 1D element type corresponding to each selected 1D element for performing FEA.
According to another aspect of the present subject matter, the system includes a processor and a memory coupled to the processor. Further, the memory includes the source FEA tool, the destination FEA tool, and a selection module. In one embodiment, the selection module selects the equivalent 1D element type in the destination FEA tool corresponding to each 1D element in the FEM of the source FEA tool for performing FEA using the method described above.
According to yet another aspect of the present subject matter, a non-transitory computer-readable storage medium for selection of an equivalent 1D element type in a destination FEA tool for 1D elements of a source FEA tool, having instructions that, when executed by a computing device causes the computing device to perform the method described above.
The system and method disclosed herein may be implemented in any means for achieving various aspects. Other features will be apparent from the accompanying drawings and from the detailed description that follow.
Various embodiments are described herein with reference to the drawings, wherein:
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
A system and method for an equivalent one dimension (1D) element type in a destination finite element analysis (FEA) tool for 1D elements in a source finite element analysis (FEA) tool are disclosed. In the following detailed description of the embodiments of the present subject matter, references are made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the present subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present subject matter, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present subject matter. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present subject matter is defined by the appended claims.
The terms “converting” and “translating” are used interchangeably throughout the document.
Referring now to
Further, 1D elements in the destination FEA tool are classified into various elements types, such as ED1, ED2, ED3, ED4, ED5, ED6, and ED7 based on the physical behavioral features. In the example illustrated in
At step 502, physical behavioral feature data associated with a 1D element (which may be of type ES2 or ES3) in the source FEA tool is read from an input deck of the associated 1D element. For example, the physical behavioral feature data includes data associated with the physical behavioral features of the 1D element. At step 504, values of shear stiffness factors associated with the 1D element are extracted using the physical behavioral feature data. For example, a first shear stiffness factor (K1) associated with the 1D element is extracted corresponding to an XY plane and a second shear stiffness factor (K2) associated with the 1D element is extracted corresponding to an XZ plane. The shear stiffness factors K1 and K2 ranges from zero to infinity. In the example illustrated in
In one embodiment, the values of K1 and K2 determine value of transverse shear stiffness. The transverse shear stiffness can be expressed using an equation:
KS1=K1AG (1)
KS2=K2AG (2)
wherein,
KS1, KS2=transverse shear stiffness,
K1 and K2=shear stiffness factors,
A=C/S area, and
G=shear modulus.
In equation (1), the values of KS1 and KS2 depend on the values of K1 and K2, respectively. For example, the values of KS1 and KS2 are equal to zero or infinity when the values of both K1 and K2 are equal to zero or infinite, respectively, and the values of KS1 and/or KS2 are not equal to zero when the values of K1 and/or K2 are not equal to zero or infinite, respectively, as values of A and G in equations (1) and (2) cannot be zero.
At step 506, a check is made to determine whether the values of K1 and K2 are simultaneously equal to zero or infinite. If the values of both K1 and K2 are simultaneously equal to zero or infinite, a user is allowed to select a type of FEA to be performed in the destination FEA tool at step 508. For example, the type of the FEA to be performed in the destination FEA tool includes a linear FEA or a non-linear FEA. In one embodiment, if the values of both K1 and K2 are simultaneously equal to zero or infinite, it implies that the values of KS1 and KS2 obtained using equations (1) and (2), respectively, are zero or infinite and the 1D element has no transverse shear stiffness, indicating it is based on Euler-Bemoulli bending theory. In this case, a set of 1D element types having no transverse shear stiffness is selected in the destination FEA tool. For example, the 1D element types having no transverse shear stiffness in the destination FEA tool are ED2 and ED3 (as shown in
When the user selects the linear FEA to be performed in the destination FEA tool, an equivalent 1D element type compatible with linear analysis is selected in the destination FEA tool from the set of 1D element types having no transverse shear stiffness at step 510. For example, the equivalent 1D element type in the destination FEA tool is selected as ED2 when the user selects that the type of FEA to be performed in the destination FEA tool is the linear FEA. At step 512, the selected equivalent 1D element type (i.e., ED2) in the destination FEA tool is stored.
When the user selects the non-linear FEA to be performed in the destination FEA tool, an equivalent 1D element type compatible with non-linear analysis is selected from the set of 10D element types having no transverse shear stiffness in the destination FEA tool at step 514. For example, the equivalent 1D element type in the destination FEA tool is selected as ED3 when the user selects that the type of FEA to be performed in the destination FEA tool is the non-linear FEA. At step 516, the selected equivalent 1D element type (i.e., ED3) in the destination FEA tool is stored.
If the values of K1 and/or K2 are greater than or equal to zero (i.e., K1 is greater than zero and K2 is equal to zero or K1 is equal to zero and K2 is greater than zero or K1 and K2 both are greater than zero), the user is allowed to select a preference for the equivalent 1D element type in the destination FEA tool at step 518. For example, the preference for the equivalent 1D element type in the destination FEA tool includes a two-node 10D element type, a three-node 1D element type and the like.
In one embodiment, if K1 and/or K2 are greater than zero, it implies that the values of KS1 and/or KS2 obtained using equations (1) and (2), respectively, are not zero and the 1D element has transverse shear stiffness. In this case, a set of 1D element types having transverse shear stiffness is selected in the destination FEA tool. For example, the 1D element types having transverse shear stiffness in the destination FEA tool are ED4, ED5, ED6 and ED7 (as shown in
When the user selects the preference as the three-node 1D element type, an equivalent 1D element type having three nodes is selected from the set of 1D element types having transverse shear stiffness at step 520. For example, the equivalent 1D element type in the destination FEA tool is selected as ED6 or ED7 when the user selects the preference for the equivalent 1D element type as the three-node 1D element type. Further, the selection of equivalent 1D element type as ED6 or ED7 is based on a user preference for a solver in the destination FEA tool. In one example implementation, the user is allowed to select a preference for the solver in the destination FEA tool. Further, the equivalent 1D element type is selected as ED6 when the selected preference for the solver in the destination FEA tool is Abaqus v6.10 or earlier. Furthermore, the equivalent 1D element type is selected as ED7 when the selected preference for the solver in the destination FEA tool is Abaqus v6.11 or later. At step 522, the selected equivalent 1D element type (e.g., ED6 or ED7) is stored.
When the user selects the preference for the equivalent 1D element type as the two-node 1D element type, an equivalent 1D element type having two nodes is selected from the set of 1D element types having transverse shear stiffness at step 524. For example, the equivalent 1D element type is selected as ED4 or ED5 when the user selects the preference for the equivalent 1D element type as the two-node 1D element type. In this example, the selection of equivalent 1D element type as ED4 or ED5 is based on user preference for the solver in the destination FEA tool. In one example implementation, the equivalent 1D element type is selected as ED4 when the user preference for solver in the destination FEA tool is Abaqus v6.10 or earlier. Further, the equivalent 1D element type is selected as Eoswhen the user preference for solver in the destination FEA tool is Abaqus v6.11 or later. At step 526, the selected equivalent 1D element type (e.g., ED4 or ED5) is stored. Further, the steps 502 to 526 are repeated for next 1D element in the FEM of the source FEA tool until the selection of the equivalent 1D element type in the destination FEA tool corresponding to all 1D elements in the FEM of the source FEA tool is completed.
Referring now to
The computing system 602 includes a processor 604, memory 606, a removable storage 618, and a non-removable storage 620. The computing system 602 additionally includes a bus 614 and a network interface 616. As shown in
Exemplary user input devices 622 include a digitizer screen, a stylus, a trackball, a keyboard, a keypad, a mouse and the like. Exemplary output devices 624 include a display unit of the personal computer, a mobile device, and the like. Exemplary communication connections 626 include a local area network, a wide area network, and/or other network.
The memory 606 further includes volatile memory 608 and non-volatile memory 610. A variety of computer-readable storage media are stored in and accessed from the memory elements of the computing system 602, such as the volatile memory 608 and the non-volatile memory 610, the removable storage 618 and the non-removable storage 620. The memory elements include any suitable memory device(s) for storing data and machine-readable instructions, such as read only memory, random access memory, erasable programmable read only memory, electrically erasable programmable read only memory, hard drive, removable media drive for handling compact disks, digital video disks, diskettes, magnetic tape cartridges, memory cards, Memory Sticks™, and the like.
The processor 604, as used herein, means any type of computational circuit, such as, but not limited to, a microprocessor, a microcontroller, a complex instruction set computing microprocessor, a reduced instruction set computing microprocessor, a very long instruction word microprocessor, an explicitly parallel instruction computing microprocessor, a graphics processor, a digital signal processor, or any other type of processing circuit. The processor 604 also includes embedded controllers, such as generic or programmable logic devices or arrays, application specific integrated circuits, single-chip computers, smart cards, and the like.
Embodiments of the present subject matter may be implemented in conjunction with program modules, including functions, procedures, data structures, and application programs, for performing tasks, or defining abstract data types or low-level hardware contexts. Machine-readable instructions stored on any of the above-mentioned storage media may be executable by the processor 604 of the computing system 602. For example, a computer program 612 includes machine-readable instructions capable for selecting the equivalent 1D element type in a FEM of the destination FEA tool 630 corresponding to each 1D element in a FEM of the source FEA tool 632 in the computing system 602, according to the teachings and herein described embodiments of the present subject matter. In one embodiment, the computer program 612 is included on a compact disk-read only memory (CD-ROM) and loaded from the CD-ROM to a hard drive in the non-volatile memory 610. The machine-readable instructions cause the computing system 602 to encode according to the various embodiments of the present subject matter.
As shown, the computer program 612 includes the selection module 628. For example, the selection module 628 can be in the form of instructions stored on a non-transitory computer-readable storage medium. The non-transitory computer-readable storage medium having the instructions that, when executed by the computing system 602, causes the computing system 602 to perform the one or more methods described in
In one embodiment, the selection module 628 selects 1D elements in the FEM of the source FEA tool 632 are selected based on associated physical behavioral features. Further, the selection module 628 extracts shear stiffness factors associated with each selected 1D element in the FEM of the source FEA tool. Furthermore, the selection module 628 selects the equivalent 1D element type in the FEM of the destination FEA tool 630 for each selected 1D element in the FEM of the source FEA tool 632 based on the extracted shear stiffness factors for performing FEA. This is explained in more detail with reference to
In various embodiments, the systems and methods described in
Although certain methods, systems, apparatus, and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. To the contrary, this patent covers all methods, apparatus, and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.
Number | Date | Country | Kind |
---|---|---|---|
2578/CHE/2014 | May 2014 | IN | national |
Benefit is claimed under 35 U.S.C. 119(a)-(d) to International Patent Application No. PCT/IN2015/000221 filed on May 25, 2015, entitled “SELECTION OF AN EQUIVALENT 1D ELEMENT TYPE IN A DESTINATION FEA TOOL FOR 1D ELEMENTS IN A SOURCE FEA TOOL” and to Indian Application Number 2578/CHE/2014 filed on May 23, 2014, entitled “SELECTION OF AN EQUIVALENT 1D ELEMENT TYPE IN A DESTINATION FEA TOOL FOR 1D ELEMENTS IN A SOURCE FEA TOOL” by AIRBUS GROUP INDIA PRIVATE LIMITED and AIRBUS OPERATIONS S.L. which is herein incorporated in its entirety by reference for all purposes.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/IN2015/000221 | 5/25/2015 | WO | 00 |