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Aging-aware optimal power management control and component sizing of a fuel cell hybrid electric vehicle powertrain

2023-01-01T00:00:00Z

Título: Aging-aware optimal power management control and component sizing of a fuel cell hybrid electric vehicle powertrain Autor(es): Silva, Samuel Filgueira da; Eckert, Jony Javorski; Silva, Fabrício Leonardo; Corrêa, Fernanda Cristina; Silva, Ludmila C. A.; Bueno, André Valente; Dedini, Franco Giuseppe Abstract: The current study presents a comprehensive approach for optimizing the power distribution control and design of a Fuel Cell Hybrid Electric Vehicle (FCHEV) equipped with a Battery-Ultracapacitor Hybrid Energy Storage System (HESS) using a multi-objective evolutionary algorithm called interactive adaptiveweight genetic algorithm (i-AWGA). The method aims to maximize the vehicle’s driving range and the lifetimes of the fuel cell stack and battery while minimizing hydrogen fuel consumption and HESS size. The energy management strategy involves fuzzy logic controllers to distribute the power demand between the fuel cell and HESS and between the battery and ultracapacitor pack. Under the combined standardized cycle in which the optimization was developed, the optimized FCHEV configuration achieved a driving range of 444 km, hydrogen consumption of 0.9009 kg/100 km. Furthermore, the optimal configuration demonstrated robustness in real-world driving conditions, exhibiting improved energy efficiency, driving autonomy, and power sources lifespan. A costbenefit analysis was also carried out, in which the optimized configuration was evaluated in terms of cost of ownership, achieving 31.28 US$/km, which means the substantial reduction of up to 63.59% in the invested cost-to-autonomy ratio as compared against other electrified vehicle powertrain topologies. Overall, this study offers a promising approach for designing efficient, cost-effective, and environmentally friendly FCHEVs with improved performance and durability. Tipo: Artigo de Periódico

Adsorption of thiophene and toluene on NaY zeolites exchanged with Ag(I), Ni(II) and Zn(II)

2009-01-01T00:00:00Z

Título: Adsorption of thiophene and toluene on NaY zeolites exchanged with Ag(I), Ni(II) and Zn(II) Autor(es): Oliveira, Mona Lisa Moura de; Miranda, Antonio Aecivanio Lins; Barbosa, Celmy Maria Bezerra de Menezes; Cavalcante Júnior, Célio Loureiro; Azevedo, Diana Cristina Silva de; Rodríguez-Castellón, Enrique Abstract: The present study evaluates the adsorption capacity of thiophene and toluene and their competitive behaviour on zeolite NaY exchanged with transition metals (5 wt% Ni, Zn and Ag). The headspace chromatography technique was used to obtain monocomponent apparent adsorption isotherms of thiophene and toluene with NaY, NiY, ZnY and AgY using isooctane as an inert solvent at 30 and 60 °C. Selectivity between toluene and thiophene at saturation capacities were also measured at 30 °C. The adsorption capacity for thiophene increased for the studied adsorbents as follows: NaY < ZnY < NiY < AgY at 30 °C and NaY < NiY < ZnY < AgY at 60 °C. Toluene is less adsorbed, but within the same order of magnitude as thiophene and following the same sorbent order. All adsorbents were moderately selectivity for tolu- ene. Nevertheless, the sulfur content was successfully reduced in the presence of aromatics and olefins in immersion tests with a model fuel mixture. These results show the importance of inserting transitions metals in the zeolitic structure to enhance the adsorption of both aromatic and sulfur containing compounds in organic liquid mixtures, which shows promise to meet environmental standards in transportation fuels. Tipo: Artigo de Periódico

Copper, mercury and chromium adsorption on natural and crosslinked chitosan films: an XPS investigation of mechanism

2011-01-01T00:00:00Z

Título: Copper, mercury and chromium adsorption on natural and crosslinked chitosan films: an XPS investigation of mechanism Autor(es): Vieira, Rodrigo Silveira; Oliveira, Mona Lisa Moura de; Guibal, Eric; Rodríguez-Castellón, Enrique; Beppu, Marisa Masumi Abstract: Although biopolymers are focusing the attention of researchers as potential adsorbents for heavy metal removal, little information is given about the properties of the resulting complexes. This information would also bring a better understanding of the mechanisms involved in metal binding to the poly-mer. XPS (X-ray photo-electron spectroscopy) is a powerful technique to investigate how metal ions bind onto these matrices. In this study, copper, chromium and mercury ions were adsorbed on natural and crosslinked (glutaraldehyde and epichlorohydrin) chitosan matrices, which present diverse functional groups and may induce different adsorption mechanisms. X-ray photoelectron spectroscopy (XPS) revealed that these metals bind to glutaraldehyde-crosslinked chitosan, differently from the other two kinds of matrices. Hence, amino group availability and the formation of new structures such as imino bonds are key factors. Copper(II) stabilization was found to be poor in glutaraldehyde-crosslinked chitosan. Conversely, Hg(II) ions present higher adsorption capacity in this kind of matrix. Chromium(VI) was reduced in all three matrices. In this case, chromium(VI) is probably not well stabilized by the functional groups of these polymers and may also undergo the action of their reducing groups. Tipo: Artigo de Periódico

On-board monitoring and simulation of flex fuel vehicles in Brazil

2016-01-01T00:00:00Z

Título: On-board monitoring and simulation of flex fuel vehicles in Brazil Autor(es): Cassiano, Demostenis Ramos; Ribau, João Filipe Pinto; Cavalcante, Francisco Sales Ávila; Oliveira, Mona Lisa Moura de; Silva, Carla Alexandra Monteiro da Abstract: On-road measurement of vehicle tailpipe emissions, analyzing the data and developing a model, is very important to identify and recommend improved design and management approaches for the transport sector. A light-duty vehicle, the flex-fuel Nissan Versa equipped with a 1.6 liter engine and manual transmission was monitored in real operation. The on-board monitoring equipment consisted of a five-gas analyzer for CO, HC(CH 4), NO x, CO 2 and SO 2 in addition to dry systems, with sample lines directly connected to the tailpipe, and an on-board diagnostics (OBD II) connector, GPS, including other additional parameters monitoring (i.e. data logger with embedded microcontrollers). The operating parameters registered in this vehicle were: vehicle speed, engine speed, fuel consumption, angle position of the throttle valve, cooling water, oil and exhaust gas temperatures. The measurements were performed using gasoline with 27%, and 100% ethanol blends (E27 and E100 respectively, where E27 is used in emission certification). The vehicle-experiment (driving pattern) was realized in an urban route in the Fortaleza City, Brazil, under typical traffic conditions. The analysis indicates that the average emission rates (kg/h) for CO are more than a factor of 10 higher to NO idling emissions. AVL CRUISE integrated with AVL BOOST software were used to model the vehicle and the flex-fuel engine engine in both certification driving cycles and real operation ones. Real operation data is used to validate the model. Tipo: Artigo de Periódico