ece r66 simulation accreditation study with radioss
DESCRIPTION
A rollover incident is one of the most fatal case among the accident scenarios for coach type vehicles. The hazard of it makes the rollover resistance an important parameter for the design of the superstructure of the bus. In order to decrease the fatality, ECE R 66 regulations is in operation at Europe. The regulation describes certain test conditions and checks the intrusions to the residual space for the approval. By the development of the technology at computing systems, computational mechanics had became quite practical and trustworthy. The type approval for the ECE R66 can be obtained by computer simulation without testing. At this work, the simulation method of the rollover will be derived with Nonlinear Explicit Method using HyperWorks software package. The aim of the work is to describe the realistic model preparation having regard to practicality and decrease the computational expenses for the RADIOSS solver.TRANSCRIPT
ECE R66 Simulation Accreditation Study with RADIOSS
Caner Kara (A. Isuzu)
Caner Kara Ahmet Salih Yılmaz
Celal Ayaz
AIOS & ITU, Geleceğin Toplu Ulaşım Otobüsü
TOTAL AREA 230,000 m2
FOUNDATION YEAR
1965
TOTAL EMPLOYEES
630
R&D 80
1965 Çelik Assembly, Producing Skoda Pick-Ups
1984 Start of the Production of Isuzu Trucks
1985 Start of N series
1987 First Midibus Production
1994 First Bus Export
1999 Moved to Şekerpınar Factory
2003 First Export to Europe
2004 First D-MAX sold to Turkey
2007 Best European Distrubitor, HOSOI SAN
100.000th vehicle produced
Selling Record «11.535 units»
2008 IMM (Isuzu Manufacturing Management) Bronze Award
2009 Government Approved R&D Center
2011 9,5 m Mass Transportation Bus «Citibus»
2013 9,5 m Intercity Coach «Visigo»
2014
12 m Mass Transportation Bus «Citiport»
HUMAN
ENVIRONMENT
TECHNOLOGHY
SAFETY
COMFORT
DESIGN PRINCIPLES
FUTURE
Validation of the virtual analysis in order to obtain the accreditation of ECE R66 approval.
GOAL
ISUZU VISIGO
- 9.5 Meters - 39 Passengers - ISUZU 4HK1E5S Engine
- Intercity Coach Model
- Launched at 2013
- Already has the approval for R66
TARGETS
Obtaining the optimum safety with virtual analysis tools
Decreasing the costs for testing and speed up the design process
Direct approval for ECE R-66 with accreditation
Rollover
- The ratio of involving fatal accidents has the highest number at coach types (% 29, TÜİK)
- Rollover crashes constitute about one-fifth of all fatal crashes
- Rollover fatality occurs above 55 km/h speed level
Photo: Andrea Booher, Georgia, 1998
- It is the most crucial scenario for fatality
• A concern of the whole superstructure of a bus • Safety • ECE R66 • Accreditation • Nonlinear Explicit • Validation of the Simulation • RADIOSS
• HyperMesh, HyperCrash
Rollover as a Design Attribute
Finite Element Model
Validation with tests
and previous validated models
New designs via validated
FE model
Old Method (Outsource) New Method (In-House)
- CAD model design - Outsourcing the
design for Rollover FE model
- Editing the design with only Rollover attribute
- Application for system approval
- First design inspired from safety studies
- The analysis made in-house
- The optimization study goes on with all attributes including Rollover
- Application for system approval
Test Procedures
- The structure need to be tilted from 800 mm altitude to a rigid plane
- Kerb weight and half of the passenger weight should be applied to the system
- Residual space defined with certain conditions
- During the test there should not
be any intrusions through the space
Photo: chinabuses.com
Model Criterias
- Element quality is standardized - 2 different welding types defined (Seamweld, Spotweld). - Mass distirubition with ADMAS
- Contact Properties (TYPE 7)
- Material Model
Material Model
Material model is a parameter that directly effects the behaviour of the simulation.
Johnson-Cook Model Thus several material tests applied to
the system.
The material values found from the internet databases does not match with the specimen produced by the manufacturer
3 Point Bending Test Welded joints could cause an error on simulation. It is importantant to see the behaviour of them.
A side joint of the Visigo bus taken as the example. The force applied to the zone is holded by weldings. 3 specimens used.
Bending Test Validation
0
2
4
6
8
10
12
14
0 10 20 30
Force [kN]
Displacement [mm]
Test and Simulation Results
SP1
SP2
SP3
SIMULATION
The elastic behaviour and matches with the simulation
Plastic behaviour is different because of the welding effects
Baysection Validation
- A baysection of the vehicle gathered and tested
- Mass added to the system for having a observable deformation
- Simulation also made with the same conditions
- The method applied here is the core of the rollover procedure
Baysection Validation
Rollover Analysis
RESULTS
- Validation of the FE model provided
- Cost reduction for tests
- Time reduction for the approval process - Engineering design opportunity
SCOPE OF FUTURE WORK
- Crash Simulations
- Computational Cost Reduction - Alternative Materials - Multi-Purpose Optimization
Thank you! Vielen Dank! Teşekkürler!
ありがとうございます!