Finite element modeling of fuel emission for thermoplastic multilayer fuel tanks with optimization of barrier properties

A numerical simulation model for the prediction of fuel hydrocarbon permeation is presented in this work. The barrier layer thickness optimization for thermoplastic multilayer fuel tanks is also considered. The diffusion model is based on the continuum approach with steady-state permeation regime across the multilayer polymeric wall. The hydrocarbon flux through the multilayer wall is determined by assuming continuity in vapor pressure at the polymer-polymer interface. Since the pinch-off zone is known to be the major source of emission per unit area, a method has been developed to automatically detect this zone at the end of extrusion blow molding process. After then, an improvement to the diffusion model has been proposed in order to evaluate adequately the hydrocarbon permeation through this specific area. Finally, a gradient-based algorithm is applied to optimize the barrier layer thickness to satisfy the total hydrocarbon fuel emission constraint for a plastic fuel tank (PFT).Peer reviewed: YesNRC publication: Ye

Experimental study and numerical simulation of preform or sheet exposed to infrared radiative heating

International conference on Advances in Materials and Processing Technology, DUBLIN, IRELAND, AUG 03-06, 1999International audienceThermoplastic processing like the injection stretch blow moulding and thermoforming processes provide the heating stage with infrared oven. This is a critical stage of the process, as the final part thickness is strongly dependent on the preform or sheet temperature distribution prior to forming. Optimisation of the infrared oven is therefore necessary. Experiments have been conducted in order to characterise the heat source of the infrared emitter and the interaction between the heaters and a semi-transparent PET sheet. An 880 LW AGEMA infrared camera has been used to determine the surface distribution of the transmitted heat flux by measuring the temperature distribution on the surface of the thermoplastic sheet. In addition, numerical simulations of the temperature distribution using control-volume method have been carried out and compared with experimental data

Preform Shape and Operating Condition Optimization for the Stretch Blow Molding Process

Peer reviewed: YesNRC publication: Ye

Modelling of Non-Linear Arterial Deformation and Friction Work during PTCA

Peer reviewed: NoNRC publication: Ye

Neuroevolutionary multiobjective methodology for the optimization of the injection blow molding process

Injection blow molding process is widely used in the industry to produce plastic parts. One of the main challenges in optimizing this process is to find the best manufacturing thickness profiles which provides the desirable mechanical properties to the final part with minimal material usage. This paper proposes a methodology based on a neuroevolutionary approach to optimize this process. This approach focuses on finding the optimal thickness distribution for a given blow molded product as a function of its geometry. Neural networks are used to represent thickness distributions and an evolutionary multiobjective optimization algorithm is applied to evolve neural networks in order to find the best solutions, i.e., to obtain the best trade-off between material usage and mechanical properties. Each solution is evaluated through finite element analysis simulation considering the design of an industrial bottle. The results showed that the proposed technique was able to find good solutions where the material was distributed along the most critical regions to maintain adequate mechanical properties. This approach is general and can also be applied to different geometries.FCT - Fundação para a Ciência e Tecnologia in the scope of the project: PEst-OE/EEI/UI0319/2014 and the European project MSCA-RISE-2015, NEWEX, with reference 73420

Mechanical effect of friction and stretching on endothelium denudation

Peer reviewed: NoNRC publication: Ye

Optimization and Performance Modeling of Osteochondral Scaffolds for Tissue Engineering

Peer reviewed: NoNRC publication: Ye

Modelling of Parison Formation and Process Optimization for Blow Moulded Parts

Peer reviewed: NoNRC publication: Ye

Towards Tissue-Mimicking Gel Phantoms for Neurosurgical Simulation

Peer reviewed: YesNRC publication: Ye

Agent Based Control for the Thermoforming Process

Peer reviewed: NoNRC publication: Ye