29 documents found, page 1 of 3
Alternative fuels for internal combustion engines
Martins, Jorge; Brito, F. P.The recent transport electrification trend is pushing governments to limit the future use of Internal Combustion Engines (ICEs). However, the rationale for this strong limitation is frequently not sufficiently addressed or justified. The problem does not seem to lie within the engines nor with the combustion by themselves but seemingly, rather with the rise in greenhouse gases (GHG), namely CO<sub>2</sub>, reje...
PLA composites reinforced with flax and jute fibers—A review of recent trends, ...
Sanivada, Usha Kiran; Mármol, Gonzalo; Brito, F. P.; Fangueiro, RaúlMultiple environmental concerns such as garbage generation, accumulation in disposal systems and recyclability are powerful drivers for the use of many biodegradable materials. Due to the new uses and requests of plastic users, the consumption of biopolymers is increasing day by day. Polylactic Acid (PLA) being one of the most promising biopolymers and researched extensively, it is emerging as a substitute for ...
Development and assessment of an over-expanded engine to be used as an efficien...
Brito, F. P.; Martins, Jorge; Lopes, Francisco; Castro, Carlos; Martins, Luís Barreiros; Moreira, A. L. N.A range extender (RE) is a device used in electric vehicles (EVs) to generate electricity on-board, enabling them to significantly reduce the number of required batteries and/or extend the vehicle driving range to allow occasional long trips. In the present work, an efficiency-oriented RE based on a small motorcycle engine modified to the efficient over-expanded cycle, was analyzed, tested and simulated in a dr...
The role of lubricant feeding conditions on the performance improvement and fri...
Brito, F. P.; Miranda, A. S.; Claro, José Carlos Pimenta; Teixeira, J. Carlos; Costa, Lucrécio; Fillon, M.Most conventional hydrodynamic journal bearing performance tools can not suitably assess the effect of lubricant feeding conditions on bearing performance, even though these conditions are known to affect important performance parameters such as eccentricity and powerloss. A thermohydrodynamic analysis suitable to deal with realistic feeding conditions has been proposed. Special attention was given to the treat...
An experimental investigation on the influence of deactivation of a groove on t...
Solghar, A. A.; Brito, F. P.; Claro, José Carlos PimentaLaboratory tests have been carried out in order to assess the influence of groove activation and deactivation on the performance of a twin axial groove steadily loaded hydrodynamic journal bearing. Temperature distribution at the oil–bush interface, oil outlet temperature, total oil flow rate, partial oil flow rate (at each groove), and motor consumption were measured for several journal speeds and loads under ...
Thermohydrodynamic modelling of journal bearings under varying load angle and n...
Brito, F. P.; Miranda, A. S.; Claro, José Carlos Pimenta; Fillon, M.; Teixeira, J. Carlos; Costa, LilianaThe performance of hydrodynamic journal bearings is affected by the conditions under which the lubricant is fed to the bearing gap. Axial grooves are often used and, depending on their location relatively to the load line, they might substantially interfere with the hydrodynamic pressure generation and the thermal behaviour of the bearing. However, many of the existing tools for predicting bearing performance a...
Influence of heat pipe operating temperature on exhaust heat thermoelectric gen...
Brito, F. P.; Martins, Jorge; Gonçalves, L. M.; Antunes, Nuno; Sousa, DiogoIncreasingly stringent targets on energy efficiency and emissions, as well as growing vehicle electrification are making attractive the electric recovery of the energy normally wasted through the tailpipe of Internal Combustion Engines. Recent developments in thermoelectrics (TE) may soon make them a viable solution for such applications. This team has been exploring the potential of using TE modules in combina...
The role of lubricant feeding conditions on the performance improvement and fri...
Brito, F. P.; Miranda, A. S.; Claro, José Carlos Pimenta; Teixeira, J. Carlos; Costa, Lucrécio; Fillon, M.The performance of hydrodynamic journal bearings is significantly affected by the conditions under which the lubricant is fed to the bearing. However, many conventional analyses are not prepared to suitably incorporate these parameters and their effect on bearing performance, due to the over-simplified way they treat them. A thermohydrodynamic analysis suitable for conveniently deal with lubricant feeding condi...
Real-life comparison between diesel and electric car energy consumption
Brito, F. P.; Martins, Jorge; Pedrosa, Delfim Duarte Rolo; Monteiro, Vítor Duarte Fernandes; Afonso, João L.Vehicle electrification is one of the strategies with higher potential for increasing the efficiency of vehicle powertrains, reducing the dependency on dwindling fossil fuel sources and meeting stringent emissions targets set by policy makers. Despite all the theoretical assessments and manufacturer’s claimed efficiency and emissions records of current vehicles, there is a lack of data concerning real life comp...
The work on hydrodynamic journal bearings carried out at Minho University in th...
Claro, José Carlos Pimenta; Miranda, A. S.; Costa, Lucrécio; Brito, F. P.; Fillon, M.The hydrodynamic journal bearing is still one of the most geometrically simple mechanical components, yet highly reliable and efficient and, above all, unique in what concerns to heavy duty – high load, high speed – support of rotating shafts. Analytical studies, not only to understand the physical basis of its performance, but also to develop practical tools for an expedite design, as well as to assure its rel...