ΥΠΟΛΟΓΙΣΤΙΚΕΣ ΜΕΘΟΔΟΙ ΣΤΙΣ ΚΑΤΑΣΚΕΥΕΣ 3o/B Mάθημα: Δικτύωμα / 2D-Truss in Batch Λεωνίδας Αλεξόπουλος, Επ. Καθηγητής Τομέας ΜΚ&ΑΕ leo@mail.ntua.gr, τηλ: 772-1666 Βοηθοί διδασκαλίας: Κανακάρης Γιώργος, Διδακτορικός φοιτητής, Τομέας ΜΚ&ΑΕ τηλ: 772-1516 Καβαλόπουλος Νίκος, Τομέας ΜΚ&ΑΕ τηλ: 772-1516
1 η Εφαρμογή: Δικτύωμα-13 Truss Εμβαδόν διατομής ράβδου: 3x10-4 m Μέτρο ελαστικότητας (ατσάλι): 2.07x 10 11 Ν/m 2 L12 6 7 8 L1 L2 L3 L4 Υπολογίστε αντιδράσεις στην βάση και την εντατική κατάσταση L13 L5 L6 L7 L8 L9 L10 L11 1 2 3 4 5
2 η Εφαρμογή: Truss in Batch Εμβαδόν διατομής ράβδου: 3x10-4 m Μέτρο ελαστικότητας (ατσάλι): 2.07x 10 11 Ν/m 2 3m 4 5 L1 L7 L3 L4 L5 L6 Υπολογίστε αντιδράσεις στην βάση και την εντατική κατάσταση L2 1 2 3 F=250N
APDL 3 MODULES: /PREP7 -------------> Preprocessor /SOLU -------------> Solver /POST1 --------------> PostProcessing MAIN COMMANDS. Try: Help, ET (Defines an element type) Help, MP (Defines Material Property) Help, n (Defines a node) Help, d (Defines DOF at nodes) Help, f (Defines Force at nodes) Help, /SOLU Help, /POST1
Preprocessing 1. START ANSYS Working Directory: C:\Users\Leonidas\2014BATCH Job Name: TRUSS-BATCH-v01 2. ENTER PREPROCESSOR APDL: /prep7 3. Define element type: LINK180 Preprocessor -> Element Type -> Add/Edit/Delete APDL: ET,1, LINK180 4. CHECK HELP FOR LINK180 5. Define the real constants: for Link1 Preprocessor -> Real Constants -> Add/Edit/Delete Cross-sectional area: 3.0E-4 APDL: r,1,3.0e-4 & APDL: r,2,4.0e-4
Type HELP, LINK180
Input Data
OUTPUT DATA: Stress, Strain
ΤΙ ΑΠΟΤΕΛΕΣΜΑΤΑ ΜΠΟΡΟΥΜΕ ΝΑ ΕΞΑΓΟΥΜΕ? element values for further processing. Element data to be stored to the results file
Επιλογή Πεπερασμένου Στοιχείου ΕΞΑΓΩΓΗ ΑΠΟΤΕΛΕΣΜΑΤΩΝ ΜΕΣΩ ETABLE e.g. LS, 1 Axial stress in element E Element Node Node
Επιλογή Πεπερασμένου Στοιχείου ΕΞΑΓΩΓΗ ΑΠΟΤΕΛΕΣΜΑΤΩΝ ΜΕΣΩ ETABLE 1 2 3 4
Material Properties 6. Define Material Properties: ADPL: mp,ex,1,2.07e11 APDL: mp,prxy,1,.3 Preprocessor -> Material Properties -> Material Models Structural -> Linear -> Elastic -> Isotropic EX= 2.07E11, PRXY= 0.30 List File Log File
7. Create nodes at truss joints: n,1,0,0,0 n,2,3,0,0 Create Nodes Preprocessor -> Modeling -> Create -> Nodes -> In Active CS 3m 4 5 L3 L4 L5 L6 L1 L7 L2 1 2 3 F=250N
Create Elements 10. Create link elements between nodes: Preprocessor -> Modeling -> Create -> Elements ->Auto Numbered->Thru Nodes 3m 4 5 E1 E7 E3 E4 E5 E6 E2 1 2 3 APDL: e,1,2 e,2,3 F=250N
Enter Solution, Apply BC/LOADS 11. Enter Solution APDL: /solu 12. Apply constraints on the model: Solution -> Define Loads-> Apply -> Structural-> Displacement -> On Nodes 3m 4 5 E1 E7 E3 E4 E5 E6 E2 1 2 3 Choose UY=0 APDL: d,1,uy,0 F=250N Choose ALL DOF Set to 0 APDL: d,3,all,0
Apply Forces 13. Apply forces on the model: Solution -> Define Loads-> Apply -> Structural-> Force/Moment -> On Nodes 3m 4 5 E1 E7 E3 E4 E5 E6 E2 1 2 3 APDL: f,2,fy,-250 14. Solve the problem: Solution -> Solve-> Current LS APDL: solve
-> Quite & Save everything -> Explore Folder and Log file -> Create new folder with log file -> Run in batch SAVE DB -> Delete and re-create new folder -> Run from ANSYS (Read Input From) -> Quit -> Parametric ANSYS (i.e. TRUSSAREA and Read From input) -> Delete and re-create new folder -> Run from MATLAB in batch!"c:\program Files\ANSYS Inc\v140\ANSYS\bin\winx64\ansys140.exe" -p ansys -dir "C:\Users\Leonidas\2014BATCHC" -j "TRUSS-BATCH-v03" -s read -l en-us -b -i "C:\Users\Leonidas\2014BATCHC\TRUSS-BATCH-v02.log" -o "C:\Users\Leonidas\2014BATCHC\file.txt"
Post Processing 15. Enter postprocessor, APDL: /post1 16. Plot the deformed shape: General Postproc -> Plot Results -> Deformed Shape APDL: pldi,1
Post Processing 17. Write out a copy of this plot to a bitmap file: Utility Menu -> PltCtrls -> Hard Copy -> To File 18. List reaction forces: General Postproc -> List Results -> Reaction Solution-> OK APDL: prrf 19. List a summary: axial force and stress in each element: General Postproc -> List Results -> Element Solution -> Highlight LineElem results 20. List the x and y direction deflections for each node: General Postproc -> List Results -> Nodal Solution -> DOF Solution -> Displacement Vector SUM
Post Processing Help,LINK1 21. Choose your output from ETABLE
Post Processing Help,LINK1 21. Choose your output from ETABLE Element Node Node LS, 1 LEPEL, 1
Post Processing 21. Choose your output from ETABLE 1 2 3 4
Όριο διαρροής ατσαλιού = 250 MPa Post Processing 21. Plot Elem Table: Axial Stress (SAXL : LS,1)
Post Processing 21. Plot Elem Table: Axial Strain (EPELAXL : LEPEL,1) Είναι η παραδοχή του small strains σωστή?
Explore APDL file
Run in Batch
Run in Batch from Matlab See also: http://www.structures.ethz.ch/education/master/optimization/fs2014pdfs/computerex/opt_comexercise_1.pdf