Search results for "Automotive engine"
showing 10 items of 486 documents
Performances improvement of a S.I. CNG bi-fuel engine by means of double-fuel injection
2009
Natural gas represents today a promising alternative to conventional fuels for road vehicles propulsion, since it is characterized by a relatively low cost, better geopolitical distribution than oil, and lower environmental impact. This explains the current spreading of Compressed Natural Gas (CNG) fuelled S. I. engine, above all in the bi-fuel version, i.e. capable to run either with gasoline or with natural gas. This characteristic, on the one hand, permits the vehicle to go even when natural gas is not available, on the other hand requires the engine to be designed to run safely with gasoline, i.e. with compression ratio lower than what natural gas would allow. Moreover the electronic co…
An Experimental Study of In-Cylinder Heat Transfer from a Pressurized Motored Engine with Varying Peak Bulk Gas Temperatures
2022
The variation of in-cylinder heat transfer with parameters such as engine speed, air-to-fuel ratio, coolant temperature and compression ratio were frequently studied in classical research. These experimentally-obtained relationships are important for improving in-cylinder heat transfer models, essential in developing CO2 reducing strategies. In this publication, a 2.0 liter compression ignition engine was tested in the pressurized motored configuration. This developed experimental setup allowed testing of the engine at speeds ranging between 1400 rpm and 3000 rpm, with peak in-cylinder gas pressures from 40 bar to 100 bar. The engine was motored using different gas compositions chosen speci…
Further Experimental Investigation of Motored Engine Friction Using Shunt Pipe Method
2019
Mechanical friction is a significant power dissipater in the internal combustion engine. In the effort of designing more efficient and less pollutant engines, friction reduction is certainly on the agenda to be investigated. Such investigation cannot be possible without an accurate measurement of the same quantity. This publication regards a continued study on the mechanical friction determination in an internal combustion engine using the Pressurised Motoring Method. In this work, the friction mean effective pressure of a four-cylinder compression ignition engine was investigated with varying engine speed and manifold pressurisation, using a dedicated high precision sensor for the correct …
Effect of the thermal storage dimensions on the performances of solar photovoltaic-thermal systems
2020
Abstract PV/T panels are innovative systems increasingly used in the building sector. As a matter of fact, in that context they allow a set of common problems to be addressed and often solved: lack of physical space and economic issues, always existing when PV and thermal panels are to be installed separately. Obviously, the main objective of PV/T panels is to enhance the electrical efficiency by cooling the PV cells, but the side positive effect is also the production of thermal energy, which can be suitably exploited with a proper configuration of the whole system and an appropriate design of its components. Their energy production and overall efficiency depend on several factors and ther…
Dynamic Lighting Strategies with Load Modulation Purposes to Reduce Peak Electrical Demand
2018
This paper proposes a study about the feasibility to modulate the indoor artificial lighting, taking into account both achievable energy savings and comfort conditions, in order to reduce lighting electric loads. In particular, it focuses on the possibility, on one hand, to decrease the luminous flux and, on the other hand, to change the Correlated Colour Temperature (CCT), in order to decrease the absorbed power. Moreover, the impact of daylight-linked control systems was considered. Finally, the possibility to combine the different technical solutions was analysed. The paper proposes the definition of daily scheduling referred to lighting energy management, in order to modulate the maximu…
Energy Saving Optimizing the Ventilation Control in a Big Shopping Center
2018
The paper investigates the potential energy savings in the context of big shopping centers, thanks to the introduction of innovative technologies able to control the ventilation according the real requirement for comfort and health of indoor spaces. The case study analyses a big shopping center, where the ventilation is realized with a centralized air-conditioning plant, working with fixed air flows. Two solutions are proposed to reduce the energy consumption for ventilation. The first considers the installation of heat recovery exchangers, the second the introduction of a control system able to modulate the air exchange, according to the real requirements. An energetic and economic evaluat…
Assessing the lighting systems flexibility for reducing and managing the power peaks in smart grids
2020
Abstract The application of “shiftable” or “modulable” load (i.e. washing machine, dishwasher, etc.) in a Smart Grid, can provide energy saving or modify the power flows in the grid, allowing a reduction of the electrical power peak. This paper explores the possibility to modulate the indoor artificial lighting to support this reduction. The study examines the impact of two different measures of power shaving. On the one hand, the change of Correlated Colour Temperature of the light source, and, on the other hand, the dimming of its luminous flux. The possibility to merge the above-mentioned technical solutions is also analyzed. Based on these strategies, several daily schedules of lighting…
Calculation of Energy Performance Indices of Daylight Linked Control Systems by Monitored Data
2017
The actual performances of Building Automation systems are often lower than the ideal ones. In order to investigate the actual performance of a Building Automation system for lighting control, a large stock of collected data, including indoor illuminance and absorbed electric power, have been presented and analysed in this paper. The measures have been taken during one year, in a laboratory located at the University of Palermo, where different lighting control systems, produced by two different manufacture companies, have been installed. As demonstrated in literature, many factors affecting energy savings’ evaluation in lighting control systems are the position and the typology of the senso…
Analysis of Load Match in Nearly Zero Energy Buildings
2018
The concept of load matching refers to the degree of agreement or disagreement of the on-site generation with the building load profiles: it can be increased and optimised with modifications on both the energy demand and generation. In this context, the paper presents the load match analysis of a case study: a modular housing construction (it has an area of 45 m 2 and S/V ratio equal to 2.75 m −1 ) built in Messina (Italy). Moreover, in order to optimize the design of the next test module to be built, a parametric analysis was performed considering different scenarios on the generation side, to explore the effectiveness of the solutions sets used in current design and plan different solutio…
A Network Tomography Approach for Traffic Monitoring in Smart Cities
2018
Traffic monitoring is a key enabler for several planning and management activities of a Smart City. However, traditional techniques are often not cost efficient, flexible, and scalable. This paper proposes an approach to traffic monitoring that does not rely on probe vehicles, nor requires vehicle localization through GPS. Conversely, it exploits just a limited number of cameras placed at road intersections to measure car end-to-end traveling times. We model the problem within the theoretical framework of network tomography, in order to infer the traveling times of all individual road segments in the road network. We specifically deal with the potential presence of noisy measurements, and t…