Durability Evaluation of Tipper Cabin

Durability Evaluation of Tipper Cabin through Virtual Multi-Axis Cab Shake Test


Ashutosh Dubey Srinivas Kurna


Objective

Life Evaluation and Underbody Design finalization of Truck Cabin for Tipper

applications

Based on Fatigue Correlation between Virtual Transient Simulation and 5-Axis Rig

Test.

To validate Life of Cab BIW & Suspensions, reducing physical endurance testing

to minimum.


Test Rig setup has been simulated along with Cabin and Truncated portion of

Chassis for calculating the Life Using FEMFAT.

Multiple design iterations life calculations using FEMFAT to reduce the cost for

several physical validations.

Challenges:


Methodology: Life Evaluation

CAE

Fatigue Life Fatigue Life

Life Correlation

Design Iterations

Correlated FE Model

Pass

Optimized Design

FEMFAT

Rig Test


Methodology: Duty Cycles generated from Tipper SLDA is used for 5-Axis Cab shake rig and Virtual Simulation

have been applied in CAE model, similar to test rig setup.

Four vertical excitations have been applied on chassis through 4 posters of test rig. One

longitudinal excitation is also applied to simulate longitudinal loads.

Test rig setup has been simulated and correlated in CAE model

Design Iterations are done Virtually and Life Target achieved through FEMFAT evaluation

Design Finalized virtually is validated by Rig Test & Vehicle Endurance No Failures observed


FEMFAT

Trans Max

Transient Stresses

Channel Max

Modal Stresses

Participation Factors

Fatigue Life Calculations Using FEMFAT:

Trans Max Vs Channel Max

Fatigue Life Fatigue Life


Trans Max Vs Channel Max


Rig Test vs. Virtual Test - Animation:


Correlation: CAE to Rig

Very good correlations have been achieved between the Test Rig vs. Virtual simulation results in Displacement/Strain time domain.


Measured Strain Damage vs. CAE Damage Values Graph over all Strain Gages

It can be observed from the above relative damage graph that damages in the CAE

results are similar to those in rig. However, they are on slightly higher side.

Therefore, CAE will have conservative results for the cabin life calculation.

0

1

2

3

4

5

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

CAE Relative Damage

Strain Gauge No.

Rel

ativ

e d

amag

e


Conclusions:

Fatigue life analysis results through FEMFAT correlates well with rig testing

results. This has improved confidence on virtual analysis, thereby helped in

reducing rig testing and vehicle endurance testing.

Virtual analysis helped in avoiding rig testing for intermediate iterations

resulting in saving of appx.17.5MINR.

This methodology has become standard practice in VECV. We are now using

same methodology for new vehicle chassis validation also.

Since Fatigue life correlation is very good, we have significantly reduced the

number of physical rig tests as well as vehicle endurance test.

Durability Evaluation of Tipper Cabin

Documents

Transcript of Durability Evaluation of Tipper Cabin