www.femfat.com FEMFAT 4.7b is available! FEMFAT 4.7b is available!
Transcription
www.femfat.com FEMFAT 4.7b is available! FEMFAT 4.7b is available!
Spring Edition 2008 - No. 14 Invitation to the FEMFAT User Meeting Japan, June 19, 2008 FEMFAT 4.7b is available! Post-Congress Party 2006 Content: Invitation to the FEMFAT User Meeting Japan, June 19, 2008 _________ 1 Apple iPod touch to be won ______ 1 64bit Release for Windows available _____________ 1 Summar y of 2 years of FEMFAT Roadshows____________ 2 FEMFAT STRAIN innovations ____ 2 FAQs: • Does the ANSYS RST inter face have any peculiarities? ______ 3 • What settings are required for importing grid point forces? ___ 3 • Can FEMFAT perform an evaluation to the Dang Van criterion _____ 3 Planned elimination of obsolete CAE-inter faces in FEMFAT ______ 3 Training - Dates _______________ 4 MAGNA FEMFAT worldwide _____ 4 Event Calendar ________________ 4 Publisher´s information ________ 4 Visit our website: www.femfat.com We are par ticularly pleased about the invitation from our Japanese distribution par tner for the TOYOTA group, Toyota Technical Development Corporation (TTDC), to hold this years FEMFAT User Meeting in the Nagoya Office, and invite all Japanese FEMFAT users and other interested parties to participate. To the accompaniment of presentations by Japanese FEMFAT users we present the newest methods andapplications on topics such as the assessment of welded structures, thermomechanical fatigue of engine components or on spot welding and self piercing rivets. Beside Toyota numerous other impor tant Japanese vehicle manufacturers, mechanical engineering and supplier companies have registered to participate. A new delegate record of more than 70 experts is anticipated. Use the Japanese FEMFAT user network to discuss applications, methods and practice with colleagues and the FEMFAT team. The event runs from 9 a.m. – 16 p.m.; more information on the FEMFAT User Meeting Japan can be obtained from the Magna Tokyo Office: Mr Kazumasa Kato, Tel: (0)3 3548 0310, Fax: (0)3 3548 0319, Cellular (0)80 3122 5737, Email: [email protected]. Address for FEMFAT User Meeting Japan: TOYOTA Technical Development Corporation, Nagoya Office (http://www.toyota-td.jp/en/), NORE Sakuradori Bldg., 2-28-23 Izumi, Higashi-ku, Nagoya, Aichi, 461-0001 Japan H. Dannbauer Apple iPod touch to be won 64bit Release for Windows available Here at FEMFAT - the software made by engineers for engineers - one of our biggest concerns is regular surveying of customer satisfaction, from the project manager through the software user to the system administrator. We therefore appeal to all our worldwide customers to fill out a small questionnaire on our website at www.femfat.com from midMay onwards. The survey is anonymous; i.e. people and answers are not stored or evaluated together. The names of those who provided feedback will be entered in a prize lottery at the end of June. The first prize is an "Apple iPod touch" (8 GB memory, only 8 mm thick,..., the ideal companion for long business trips or traffic jams); winners 2 to 10 will receive a USB flash memory. We thank you in advance for your participation. After prolonged and tenacious effor ts by our developers it is now (finally) available: the 64-bit Beta Release for Windows XPx64, Vistax64 and Server 2003x64 is available for download on our website. A. Werkhausen C. Gaier This version allows very large FEM models, containing several million elements, to be analyzed, depending on the available RAM. The 2 GB RAM limitation, familiar from 32 bit systems, is eliminated. This version has been exhaustively tested; it is only referred to as a beta version because problems with the Medina interface have not yet been satisfactorily solved. The Win64 version code is identical to that of version 4.7b. We hope that numerous users take advantage of this and look for ward to receiving any kind of feedback. FEMFATNEWSLETTER Spring Edition 2008 - No. 14 Summary of 2 Years of FEMFAT Roadshows We have now been organizing roadshows in Europe for 2 years under the banner of "Closer to the customer". The dual model of a serious informational event for interested parties and as a topical discussion platform for existing customers has proven highly successful and we will expand this model to cover North America. Overall, a total 170 visitors attended 9 events; we believe this is an optimum frequency, both justifying the effor t and allowing individual consultations. We wish the support and distribution staff under Axel Werkhausen continued success! H. Dannbauer FEMFAT STRAIN Innovations It is possible to visualize both stains and stresses (see the following example of stresses from TransMAX). Version 4.7 includes a number of improvements and innovations in the STRAIN module. The strain gages can now be ver y easily defined in the shape of tables, both in the STRAIN sub-module "Calc" for evaluating strain histories regarding damage, as well as in "Comp" for comparing measured strain histories with FEMFAT results: CompSTRAIN has been integrated into BASIC and MAX and can now be utilized either together with a damage/fatigue safety analysis or separately. The label, name, modeling method, strain gage type (linear, 45° rosette, 60° rosette), element and node numbers, input file, column numbers, initial strain, dimensions, multiplication factor and repetition factor are specified for the columns. Particular attention was paid to the simplicity of defining the position, direction and length of the strain gage. It is possible to use folded triangular elements, just as before; however, the onerous labeling of nodes and elements with colors and material IDs is no longer necessary, the element label data in the table suffices. If it is nevertheless necessary to use the old labeling method, this is possible by specifying the element label "0". The CTR (center) option determines the FEM stress at the center node of the triangular element by interpolation using element shape functions and projection in the strain gage direction. Using the ALL option, in contrast, the stress is integrated and averaged over the entire length of the strain gage, providing better comparison data to the test in zones with higher gradients. The N2N ("node to node") option provides a simple option for specifying the position and direction of the strain gage. In this case only two nodes need to be specified, whereby the first node defines the position of the strain gage and the second node the direction. In FEMFAT MAX the histories of measured strains and FEM results can now be visualized superimposed and thus be directly compared to each other. CalcSTRAIN allows measured strain signals to be utilized for strength analyses using the FEMFAT method. This does not even require an FEM model - contrary to our tradition - but only material properties, etc. However, the advantages of a consistent comparison between computations and measurements are obvious. In summar y, we believe that STRAIN now represents a technically considerably more attractive product at an unchanged price. Finally, an important practical note is given here: Because CalcSTRAIN's memory requirement is currently relatively high the settings in the femfat.ini file should be optimized. (No special measures are required for CompSTRAIN!) An excerpt of possible setting for the femfat.ini file is reproduced below: Maximum number of nodes Maximum number of elements Highest allowable node-label Highest allowable element-label Average number of nodes per element FEMFAT MAX: Maximum number of channels FEMFAT MAX: Maximum number of samples per channel FEMFAT MAX: Maximum number of samples over all channels FEMFAT MAX: Maximum number of cutting planes FEMFAT STRAIN: Maximum number of strain gauges 10 10 10 10 12 3 200000 600000 18 30 In addition, the defined repetition factor should not be too large (< 100). K. Hofwimmer 2 FEMFATNEWSLETTER Spring Edition 2008 - No. 14 FAQs A curve with the following mean stress sensitivity M (corresponds to a negative curve slope) has to be specified as the Haigh diagram for tension/compression mean stresses: Does the ANSYS RST interface have any peculiarities? In order to import the results of an ANSYS analysis into FEMFAT in a binary *.rst file, please ensure that the finite element structural data is also included. FEMFAT also requires this data when importing the results. If the ANSYS settings are left on "Default" there will not be any problems. However, if the command "NO_RSTGM=1" is included in the configuration file the necessar y information will be missing and FEMFAT aborts importing the results from *.rst. E. Dutzler What settings are required for importing grid point forces? If the nodal forces are to be impor ted for a FEMFAT SPOT (JSAE method) or FEMFAT WELD (SSZ/MSZ method) analysis, the corresponding check box (see figure) must first be activated. This option prevents excessive memor y use. Note: Node forces can currently be imported from NASTRAN op2 and MEDINA bof. (4) There are now two options available for def. Haigh diagrams in FEMFAT: 1. Standard design using material parameters, which must be appropriately adapted: For the pulsating tensile strength limit (defined in FEMFAT as the upper stress) this results in: (5) For the pulsating compressive strength lower-stress) this further results in: (6) (define in FEMFAT as the And finally, for the fictitious tensile strength Haigh-diagram in FEMFAT: used to close the (7) Disadvantage of standard design: A Dang Van assessment can no longer be carried out for high compressive mean stresses, which are greater than the pulsating compressive strength, see Fig. 1 2. User-defined Haigh diagram: In this case it is sufficient to specify two points in a table to define the curve. GUI for the node forces in BASIC GUI for the node forces in MAX E. Dutzler Can FEMFAT perform an evaluation to the Dang Van criterion? Professor Dang Van, currently engaged at the École Polytechnique, Palaisea Cedex, developed an endurance stress limit criterion during the 1970s, making him world famous in the fatigue community. FEMFAT does not directly offer the Dang Van criterion, but results generally corresponding to the Dang Van criterion can be achieved by using suitable settings for the material and analysis parameters. According to Dang Van's hypothesis material failure does not occur if the following condition is fulfilled for the entire load cycle: (1) is the shear stress amplitude and the hydrostatic stress component, a and b are material parameters that allow the tensile/compressive and alternating shear stress to be computed for FEMFAT: (2) (3) If an endurance safety factor analysis is carried out in FEMFAT MAX using the default "Scaled normal stress in critical cutting plane" method, exactly the same results are achieved for superimposed alternating bending and torsional loads with phase shift as for the Dang Van method. The situation is somewhat more complex for existing mean stresses. A differentiation is made between tensile/compressive (or bending) or torsional mean stresses. Fig. 1: Haigh diagram for evaluation according to Dang Van, blue: standard design, green: user-defined For torsional mean stresses there is no mean stress influence after Dang Van; however more recent research has shown that this is only true for small values. In this case it is possible to deactivate the mean stress influence in FEMFAT. However, in many cases the exact load situation is not known and may var y in location and time. Analysis using the above mean str ess influence for tension/compression is then recommended. This will then produce conservative results. Finally, please note that the Dang Van model does not take the support effect in notches into consideration. The stress gradient influence in FEMFAT can therefore be deactivated for an evaluation after Dang Van. However, because the results may be considerably C. Gaier Planned Elimination of obsolete CAE-Interfaces in FEMFAT It is planned to no longer support the following interfaces from FEMFAT 4.8 onwards: • SDRC I-DEAS VI-i Universal - Import FEM entity, stress, temperature, sec. dendrite arm spacing - Export FEMFAT results • INTERGRAPH Neutral (import FEM entity) • ANSYS GEOWRITE (import FEM entity) • TOSCA ONF 520 (export FEMFAT results), new ONF600+601 • STEYR dataset 205 (import load history into ChannelMAX). If (contrary to expectations) one of these interfaces is still required, please contact us before the end of June 2008 at the latest. C. Gaier 3 FEMFATNEWSLETTER Spring Edition 2008 - No. 14 Training - Dates 2008 Engineering Center Steyr, St. Valentin 3.-4. June 6.-7. August 15.-16. October 3.-4. December Fatigue life/Damage and safety factors for simple loads, comprehensive FE-interfaces and material database Engineering Center Troy, Detroit 29. February 18. June 11. September 18. December Prices (excl. VAT.): per delegate per additional delegate from the same company University/Research group Euro 770,Euro 610,Euro 300,- Including 2 months FEMFAT evaluation license Information: [email protected] 3D-postprocessor and WELD definition Magna Powertrain Engineering Center Steyr GmbH&Co.KG Structural Analysis Department Steyrer Straße 32, 4300 St. Valentin, Austria Phone +43 7435 501 336 Fax +43 7435 501 300 E-Mail: [email protected] Multiaxial fatigue Magna Powertrain Engineering Center Troy 1775 Research Drive, TROY, MI 48083 Phone +1 248-680 4919 Fax +1 248 524 5570 E-mail: [email protected] Magna International Japan Inc. 2-1-6 Chuo-ku, Yaesu k Building 5F 104 0028 TOKYO TEL +81 (0)3 3548 0310 FAX +81 (0)3 3548 0319 Mobile +81 (0)80 3122 5737 E-mail: [email protected] Welded structures Spot-joined structures Magna International China 801-813, Tower A, Eton Place, 69 Dongfang Road, Pudong Shanghai PRC 200120 Tel: +86-21-6165 1500(Master Line) ext.6649 Tel: +86-21-6165 1652, Fax: +86-21-6163 9099 Mobile: +86-15900861655 E-mail: [email protected] Thermo-mechanical fatigue PLAST Local plasticity Magna Steyr India Pvt. Ltd. Survey No. 55, Hissa No. 1 Bavdhan Khurd Dist-Pune- 411021 Phone +91 20 6675 1000 E-mail: [email protected] BREAK Static safety factors STRAIN Virtual strain gage/ Measured strain damage FEDIS Sub-modeling Event Calendar Engine dynamics/Acoustics simulation Analysis & preparation of data Publisher's Information: Engineering Center Steyr GmbH & Co KG Steyrer Strasse 32, 4300 St. Valentin, Austria Tel: +43 7435 501 303, Fax: +43 7435 501 300 [email protected] 4 SF2M Conference “Fatigue and Plasticity” 2. Conference f. Applied Optimization in Virtual Prod. Develop. SCT 2008 Symp. Structural Durability/LBF FEMFAT Roadshow Berlin FEMFAT User Meeting Japan RELMAS St. Petersburg FISITA Munich ISMA Noise and Vibration Engineering Conference 17th Aachen Colloquium Automobile and Engine Technology 35th Conf. of the DVM Working Group on Operat. Strength FEMFAT Roadshow Bologna FEMFAT User Meeting North America SIMVEC - Calculation and Simulation in Vehicle Engineering FEMFAT Roadshow Aachen Paris Karlsruhe Wiesbaden Darmstadt Berlin Nagoya St. Petersburg Munich Leuven Aachen Sindelfingen Bologna Troy Baden-Baden Aachen 20.-22.05.2008 03.-04.06.2008 01.-05.06.2008 05.-06.06.2008 10.06.2008 19.06.2008 24.-26.06.2008 14.-19.09.2008 15.-17.09.2008 6.-8.10.2008 8.-9.10.2008 4.11.2008 6.11.2008 26.-27.11.2008 16.12.2008