Sensitivity Analysis on the Sizing Parameters of a Series-Parallel HEV

AAC 2019, 9th IFAC Symposium on Advances in Automotive Control, ORLEANS, FRANCE, 23-/06/2019 - 27/06/2019As an alternative to power-split hybrid architectures, a simple series-parallel architecture named SPHEV 2 can be realized. In this paper, the sizing process of this architecture is briefly presented and a deeper analysis is made. Mathematical sensitivity analysis studies are conducted on the sizing parameters of the architecture in order to bring more understanding to the optimization results. Local and global sensitivities are performed to understand the influence of the sizing variables on the fuel consumption. An analysis of the sensitivities is also made

Brayton cycles as waste heat recovery systems on series hybrid electric vehicles

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Fuel Consumption Saving Potential of Stirling Machine on Series Parallel Hybrid Electric Vehicle: Case of the Toyota Prius

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Operating Limits for Ammonia Fuel Spark-Ignition Engine

The objective of this paper is to provide new data about the possibility of using ammonia as a carbon-free fuel in a spark-ignition engine. A current GDI PSA engine (Compression Ratio 10.5:1) was chosen in order to update the results available in the literature mainly obtained in the CFR engine. Particular attention was paid to determine the lowest possible load limit when the engine is supplied with pure ammonia or a small amount of H2, depending on engine speed, in order to highlight the limitation during cold start conditions. It can be concluded that this engine can run stably in most of these operating conditions with less than 10% H2 (of the total fuel volume) added to NH3. Measurements of exhaust pollutants, and in particular NOx, have made it possible to evaluate the possibility of diluting the intake gases and its limitation during combustion with pure H2 under slightly supercharged conditions. In conclusion, the 10% dilution limit allows a reduction of up to 40% in NOx while guaranteeing stable operation

Experimental investigation and 1D analytical approach on convective heat transfers in engine exhaust-type turbulent pulsating flows

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Utilisation de la combustion solide dans les machines thermiques

International audienceLes problèmes tels que le changement climatique et le réchauffement planétaire sont liées à la consommation des carburants fossiles. Malgré des systèmes de conversion d'énergie propre déjà existants, notre incapacité actuelle à stocker massivement cette énergie est le principal obstacle au développement de ces solutions alternatives aux combustibles fossiles. Pour répondre à ce défi, une solution consiste à développer un nouveau vecteur énergétique basé sur des poudres métalliques. En effet, la combustion métallique est fortement exothermique et les oxydes formés par cette réaction peuvent être recyclés par des procédés alimentés avec de l'énergie renouvelable. Ce vecteur énergétique fonctionnerait ainsi en boucle fermée et sans générer de gaz à effet de serre sur l'ensemble de son cycle. En revanche, les propriétés fondamentales et les structures de ces flammes hétérogènes métalliques sont encore méconnues, avec des écarts constatés dans la littérature. Dans ce contexte, un brûleur de type Bunsen capable de stabiliser une flamme Aluminium/Air a été développé et permet ainsi la caractérisation de ces flammes à l'aide de différents diagnostiques optiques. Les estimations de la vitesse et de la température de flamme obtenues démontrent la possibilité d'exploiter le potentiel énergétique des poudres d'aluminium, constituant ainsi une alternative crédible aux combustibles fossiles grâce à ses propriétés de combustion et sa grande disponibilité sur terre

Dynamic Modeling and Fuel Consumption Potential of an Intercooled Regenerative Reheat Gas Turbine Auxiliary Power Unit on Series Hybrid Electric Vehicle

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Investigation of Heat Energy Storage Systems for Internal Combustion Engine Applications

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Waste heat recovery from engine coolant on mild hybrid vehicle using organic Rankine cycle

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Efficiency Improvement of a Series-Parallel Hybrid Electric Powertrain by Topology Modification

Among Series-Parallel Hybrid Electric Vehicle (SPHEV) powertrains, the Power-Split architecture with a planetary gear has an exemplary energetic efficiency in mixed driving conditions. Nevertheless, a simple SPHEV architecture can be realized without a planetary gear. It consists of 2 Electric Machines (EM) mounted on the engine shaft and separated by a clutch. With no power-split operation, this architecture allows the vehicle to operate in pure electric, or series hybrid, or parallel hybrid mode. It was proven to be less efficient than a reference Power-Split SPHEV: the Toyota Hybrid System (THS). The aim of this paper is to investigate the potential of efficiency improvement of the simple SPHEV powertrain by topology modification: the addition of gears for the components or a gearbox with few number of ratios. Two new variants of SPHEVs are proposed. The versions of SPHEVs and the reference THS are optimized by a bi-level optimization technique using Genetic Algorithm and Dynamic Programming. Compared to the simple SPHEV, results show an efficiency worsening in one variant and an efficiency improvement in another variant with a fuel consumption comparable to the one of THS. A global sensitivity study is then performed on the worsened variant. The sensitivities of the added gears are determined and an elimination of some is suggested. A new variant with fewer gears is therefore proposed and optimized. The efficiency is improved but remains less than the one of THS