9162020 Correlation of Tipper Frame Failure Resolution by
9/16/2020 Correlation of Tipper Frame & Failure Resolution by Using FEMFAT a Srinivas Kurna Ashutosh Dubey
Objective: Life Evaluation and Design Finalization of Truck Frame • Based on Fatigue Correlation between Virtual Transient Simulation and Accelerated Endurance Test (AET) • To Validate Life of product, reducing physical endurance testing to minimum 2
Challenges: Complete Vehicle Modelling in Virtual Domain - includes Frame, Cabin, Axles with its wheel ends and tyres AET Track Simulation in Virtual Domain - for Fatigue life calculation Sensitivity Analysis – Difference between Designed Vs Manufacturing parameters on Strength/Stiffness of frame Correlation between the Physical and Virtual Testing - in terms of Acceleration, Displacement in Time domain and Frequency domain as well as in Fatigue domain of the Hot spots/failure locations 3
Methodology: Life Evaluation CAE AET RLDA Accelaration/Strain Fatigue Life Correlation Correlated Model Design Iterations Optimized Model Pass AET
AET - Torture Tracks Pave 5
AET - Torture Track Results Crack Observed 6
Virtual Simulation on Tracks 7
Virtual Simulation Results Life Evaluation- FEMFAT Influ. factors As per Design Physical Test. Crack Observed Virtual Simulation. Safe 8
Sensitivity Analysis Investigation- Parameters that may affect Strength/Stiffness of frame Ø Observed Gap in lateral direction between the Subframe & Spring loaded bolt mounting Bracket Ø Spring Loaded Bolt was also fully tightened, leading to lost in flexibility due to spring loaded bolt 35 Ø Bump Stopper Gap 9
Correlations- Physical Vs Virtual Correlations Activity has been performed to increase confidence between Physical and Virtual simulation Very good correlations have been achieved between the Physical vs. Virtual simulation results in Displacement/Acceleration in time & frequency domain Chassis : Vertical Displacement 10
Correlations- Physical Vs Virtual Very good correlations have been achieved between the Physical vs. Virtual simulation results in Displacement/Acceleration in time & frequency domain Axle : Vertical Acceleration 11
Correlations- Physical Vs Virtual Very good correlations have been achieved between the Physical vs. Virtual simulation results in Displacement/Acceleration in time domain Chassis : Rear Portion Vertical Displacement 12
Virtual Simulation Results Life Evaluation- FEMFAT Influ. factors Incorporating Design Gaps Physical Test. Crack Observed Virtual Simulation. Safe 13
Sensitivity Analysis Deep Investigation Poor Surface Finish 14
Virtual Simulation Results Life Evaluation- FEMFAT i ys h P h l wit Surface Roughness ults s e r s e u g i t Fa ysi l a n fe a t gh u o r h F AT EMF g el w s e t rrela co li Physical Test. Crack Observed-1513 Cycles tin s e t cal Incorporating Manufacturing Gaps Virtual Simulation. Very Low Life- 1432 Cycles 15
Conclusions By incorporating Manufacturing tolerances and Surface Roughness parameters through FEMFAT, Virtual results correlates well with AET FEMFAT has helped us to identify the failure with good Correlation. Thereby helped in reducing Design Iterations on AET Helped in avoiding AET testing for all the intermediate iterations resulting in saving of appx. 50 MINR 16
17
- Slides: 17