CAE analysis of an intake valve for bike application. C. Carapellucci, L. Nuti, R. Testi Piaggio & C. SpA Italy (

Transcription

1 CAE analysis of an intake valve for bike application C. Carapellucci, L. Nuti, R. Testi Piaggio & C. SpA Italy ( ME

2 Presentation outline Company profile Object of the study Analysis methodology Results Synopsis

3 Company profile Piaggio Group Business areas 2-wheelers Commercial Vehicles Engines Spare parts and accessories

4 Brands managed Company profile Piaggio Group

5 Company profile Piaggio Group A few figures one of the world s top four manufacturers of two-wheel motor vehicles consolidated leadership position on the European 2-wheeler market approximately 7,000 employees facilities: Pontedera (Pisa-Italy); Scorzè (Venice-Italy); Mandello del Lario (Lecco-Italy); Barcelona (Spain); Baramati (India) R&D centres: Italy, Spain, China and India vehicle sold in 2008: 648,600 net sales in 2008: 1,570 million Euro

6 Presentation outline Company profile Object of the study Analysis methodology Results Synopsis

7 Aprilia Shiver Object of the study New 1200 cc twin engine Intake valve Max power 103 kw Max torque 120 Nm Trouble-shooting activity

8 Failure during bench test Object of the study Possible culprits Incorrect test setup, procedure, Component supply issues Bad design CAE activity Good outcome

9 Presentation outline Company profile Object of the study Analysis methodology Results Synopsis

10 Analysis methodology CAD software Geometry CFD softwares Thermal BCs ANSYS Workbench (thermal) ANSYS Workbench (mechanical) Software for dynamic simulation of timing mechanisms Safety factor (thermal effects) Therma l stresse s Load/stres s transfer functions Durability software Mechanical loads Durability software Safety factor (mechanical effects)

11 Thermal BCs Geometry Analysis methodology ANSYS/Workbench analyses Steady-state thermal Transient thermal Static structural Static structural Initial condition Thermal load Thermal stresses Load/stress transfer functions

12 Analysis methodology - ANSYS/Workbench analyses - Thermal analyses (1/4) Fluid interfaces Convection BCs

13 Analysis methodology - ANSYS/Workbench analyses - Thermal analyses (2/4) mean values steady-state analysis constant

14 Analysis methodology - ANSYS/Workbench analyses - Thermal analyses (3/4) ConstantTemperature BCs Solid interfaces

15 Analysis methodology - ANSYS/Workbench analyses - Thermal analyses (4/4) 60 engine cycles analysed

16 Thermal BCs Geometry Analysis methodology ANSYS/Workbench analyses Steady-state thermal Transient thermal Static structural Static structural Initial condition Thermal load Thermal stresses Load/stress transfer functions

17 Analysis methodology - ANSYS/Workbench analyses - Load/stress TFs Load channels internal spring Unit forces external spring seat cam Resulting stress fields load/stress transfer functions

18 Analysis methodology CAD software Geometry CFD softwares Thermal BCs ANSYS Workbench (thermal) ANSYS Workbench (mechanical) Software for dynamic simulation of timing mechanisms Safety factor (thermal effects) Therma l stresse s Load/stres s transfer functions Durability software Mechanical loads Durability software Safety factor (mechanical effects)

19 Unit forces Durability Analysis input Analysis methodology Durability analyses Engine speed Stress tensor time-history Load/stress TFs Forces on valve Linear combination

20 Analysis methodology Durability analyses Critical plane method for multi-axial stress states Goodman correction for mean stress Relative stress grdient effect

21 Presentation outline Company profile Object of the study Analysis methodology Results Synopsis

22 End time temperature field Results -Transient thermal Hot point temperature vs time (last 10 engine cycles) Transient not over at the end of simulation

23 Transient not over at the end of simulation Results -Transient thermal Extrapolation End-of-transient conditions Material properties evaluation T END

24 Results - From thermal to fatigue UTS Valve temperature T END

25 Results - Durability analyses - Safety factor distribution Thermal stress effect Min value = 10.3 Min value = 1.6 Mechanical stress effect Negligible thermal effect Design soundness proved

26 New engine Synopsis Bench test failure CAE troubleshooting Easy input of complex BCs from different CAE tools Smooth data transfer between FEM models due to WB project structure Trouble-free export of FEM data to durability package Thank you for your patience! Central role of Ansys/WB Safety factor Contribution of diverse stress sources Design soundness proved