The project MATISSE funded by European Commission’s 7th Framework Programme (FP7) aims to make a significant step forward in the capability of the automotive industry to model, predict and optimise the crash behaviour of mass produced fibre reinforced polymers (FRP) with the focus set on components for alternatively powered vehicles (APV). One of the project’s main research goals is the development of a general virtual testing methodology (VTM) for the development of APV driven by compressed natural gas (CNG) equipped with composite FRP tanks of Type IV.

Due to the increasing legislative demands on the emission of future vehicles, the development of APVs that are in this regard superior to conventional internal-combustion engines (ICE) driven by petrol or diesel fuel is currently in the centre of attention of the automotive industry. Here, the usage of ICE with CNG supply offers advantages in comparison to other concepts, since it requires only moderate modifications of the conventional drive train. Because of the high mechanical demands on the required high-pressure storage tanks and the need for lightweight structures, which also contributes to the emission reduction, the usage of material of high specific material properties is required. Especially the full composite tanks of the Type IV show a high potential in this regard. Since these high-pressure storage components form a significant safety hazard, the accurate analysis of the mechanical demands during relevant crash load cases is of great importance. For the proper and optimal integration of the tanks into the vehicle during the APV design and development process at industrial level, moreover the predictability of the material and component behaviour using the finite element method (FEM) is indispensable.

Within the MATISSE project a new overall approach for the crash analysis of CNG tanks is proposed. This paper describes the main aspects of this VTM:​

First, a FRP material modelling approach for wet wound CNG tanks, that makes use of the so-called “reverse FEM” as well as of novel physically based material models that are fed with calculative as well as literature based material values and are validated on three point bending tests of wound tubes was defined.

Then, the derived material models for glass and carbon fibre were subsequently used for the modelling of FEM tank models, whereby different steps of optimisation of on the one hand the accuracy and on the other hand the simulation time were conducted.

In a next step, different relevant load cases on a full vehicle model of a compact car equipped with a CNG tank where simulated and analysed. The detected highest mechanical demands were thereupon transferred to a component test programme on a tank-subsystem that depicts the loads obtained by the tanks. Here again, the FEM model of the tank is used to find the appropriate boundary conditions.

The developed test programme was subsequently conducted on a series of physical tanks and the simulation approach and thus the VTM was validated on the results.