Impact of intake valve strategies on fuel consumption and knock tendency of a spark ignition engine

Teodosio, Luigi; Pirrello, Dino; Berni, Fabio; Bellis, Vincenzo De; Lanzafame, R.; D'Adamo, Alessandro

doi:10.1016/j.apenergy.2018.02.032

Cited by 64 publications

(27 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Constant temperatures have been assigned at each wall surface; temperature levels have been differentiated for innerliner, rim and side-wall surfaces, basing on the available experimental data for the examined tyre. More details about the 3D CFD model meshing and setup can be found in previous authors' works [27,28,41,42]. In Table 2 the case studies at different angular velocities are reported, while in Table 3 the temperatures at the walls are shown representing the typical average wall temperatures of a passenger tyre.…”

Section: Cfd Modelmentioning

confidence: 99%

“…In the present paper a hierarchical integrated numerical procedure is adopted for the first time for the tyre thermal study. The integration of different numerical procedures has been already employed in the fluid-dynamic field, especially for turbulent flows [27][28][29] which play a significant role in thermal studies. In this work, the relevant thermal parameters computed by a full 3D CFD model of tyre internal chamber are used in the fully described 3D wheel thermal model with the specific purpose of describing the tyre thermodynamic convective behaviour in realtime.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A numerical methodology for thermo-fluid dynamic modelling of tyre inner chamber: towards real time applications

et al. 2021

Self Cite

View full text Add to dashboard Cite

The characterization and reproduction of tyre behaviour for vehicle modelling is a topic of particular interest both for real-time driver in the loop simulations and for offline performance optimization algorithms. Since the accuracy of the tyre forces and moments can be achieved by the accurate physical modelling of all the phenomena concerning the tyre-road interaction, the link between the tyre thermal state and the tyre frictional performance turns into a crucial factor. An integrated numerical methodology, allowing to couple the full 3D CFD (Computational Fluid Dynamics) flux within the internal chamber of the tyre with an equivalent discrete 3D structure model, is proposed with the aim to completely represent the tyre thermodynamic convective behaviour in the steady-state operating conditions. 3D CFD model enables the evaluation of the internal distribution of the gas temperature and of the thermal powers exchanged at each sub-wall in detail. This allows to increase the reliability of the tyre thermodynamic modelling with a particular reference to the proper managing of the aero-thermal flow of the brake disc impact on the rim temperature and therefore on the internal gas dynamics in terms of temperature and pressure, being able to optimize the tyre overall dynamic performance in both warm-up and stabilized thermal conditions. The steady RANS (Reynolds Averaged Navier–Stokes) simulations have been performed employing the 3D CFD model in a wide range of angular velocities with the aim to calculate the convective thermal flux distributions upon rim and inner liner surfaces. The simulation results have been then exploited to derive the convective heat transfer coefficients per each sub domain to be employed within the real-time tyre physical thermal model, with the peculiar advantage of an enhanced model reliability for thermal characteristics. To validate the proposed methodology, the tyre thermal model outputs, in terms of temperatures of internal and external layers, have been validated towards the acquired ones within the specific routine performed on tyre force and moment test bench, confirming an excellent agreement with the experimental data in the entire range of operating conditions explored.

show abstract

Section: Cfd Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

A numerical methodology for thermo-fluid dynamic modelling of tyre inner chamber: towards real time applications

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…As expected, strategy #1 favored a higher boosting by On a general viewpoint at both low and high loads, IVC is selected near to the most advanced timing setting. This option, as said, is preferred for minimizing the pumping losses at low loads and mitigating the knock occurrence at high loads [37]. In the medium BMEP range, especially for strategy #2, IVC is slightly delayed, allowing for higher air flow rates and resulting in a better agreement with the Opt outcomes.…”

Section: Bmep Barmentioning

confidence: 99%

Optimal Calibration Strategy of a Hybrid Electric Vehicle Equipped with an Ultra-Lean Pre-Chamber SI Engine for the Minimization of CO2 and Pollutant Emissions

et al. 2020

Self Cite

View full text Add to dashboard Cite

The complexity of modern hybrid powertrains poses new challenges for the optimal control concerning, on one hand, the thermal engine to maximize its efficiency, and, on the other hand, the vehicle to minimize the noxious emissions and CO2. In this context, the engine calibration has to be conducted by considering simultaneously the powertrain management, the vehicle characteristics, and the driving mission. In this work, a calibration methodology for a two-stage boosted ultra-lean pre-chamber spark ignition (SI) engine is proposed, aiming at minimizing its CO2 and pollutant emissions. The engine features a flexible variable valve timing (VVT) control of the valves and an E-compressor, coupled in series to a turbocharger, to guarantee an adequate boost level needed for ultra-lean operation. The engine is simulated in a refined 1D model. A simplified methodology, based on a network of proportional integral derivative (PID) controllers, is presented for the calibration over the whole operating domain. Two calibration variants are proposed and compared, characterized by different fuel and electric consumptions: the first one aims to exclusively maximize the brake thermal efficiency, and the second one additionally considers the electric energy absorbed by the E-compressor and drained from the battery. After a verification against the outcomes of an automatic optimizer, the calibration strategies are assessed based on pollutant and CO2 emissions along representative driving cycles by vehicle simulations. The results highlight slightly lower CO2 emissions with the calibration approach that minimizes the E-compressor consumption, thus revealing the importance of considering the engine calibration phase, the powertrain management, the vehicle characteristics, and its mission.

show abstract

“…The latter represents a K-k-T model, which solves three balance equations to furnish the engine cycle evolution of mean flow kinetic energy (K), turbulent kinetic energy (k) and tumble vortex momentum (T) [27]. In previous authors' works [27,28], the adopted turbulence model was proved to adequately estimate the in-cylinder turbulence parameters at varying the engine speeds and the valve strategies, without a model tuning variation. A kinetically-derived LFS correlation, included within the fractal burning rate, is adopted because of its better prediction capabilities with respect to the experimentally-derived LFS formulations [29].…”

Section: Engine Modelingmentioning

confidence: 99%

Individual Cylinder Combustion Optimization to Improve Performance and Fuel Consumption of a Small Turbocharged SI Engine

Marchitto¹,

Tornatore²,

Teodosio³

2020

Energies

Self Cite

View full text Add to dashboard Cite

Stringent exhaust emission and fuel consumption regulations impose the need for new solutions for further development of internal combustion engines. With this in mind, a refined control of the combustion process in each cylinder can represent a useful and affordable way to limit cycle-to-cycle and cylinder-to-cylinder variation reducing CO2 emission. In this paper, a twin-cylinder turbocharged Port Fuel Injection–Spark Ignition engine is experimentally and numerically characterized under different operating conditions in order to investigate the influence of cycle-to-cycle variation and cylinder-to-cylinder variability on the combustion and performance. Significant differences in the combustion behavior between cylinders were found, mainly due to a non-uniform effective in-cylinder air/fuel (A/F) ratio. For each cylinder, the coefficients of variation (CoVs) of selected combustion parameters are used to quantify the cyclic dispersion. Experimental-derived CoV correlations representative of the engine behavior are developed, validated against the measurements in various speed/load points and then coupled to an advanced 1D model of the whole engine. The latter is employed to reproduce the experimental findings, taking into account the effects of cycle-to-cycle variation. Once validated, the whole model is applied to optimize single cylinder operation, mainly acting on the spark timing and fuel injection, with the aim to reduce the specific fuel consumption and cyclic dispersion.

show abstract

Impact of intake valve strategies on fuel consumption and knock tendency of a spark ignition engine

Cited by 64 publications

References 46 publications

A numerical methodology for thermo-fluid dynamic modelling of tyre inner chamber: towards real time applications

A numerical methodology for thermo-fluid dynamic modelling of tyre inner chamber: towards real time applications

Optimal Calibration Strategy of a Hybrid Electric Vehicle Equipped with an Ultra-Lean Pre-Chamber SI Engine for the Minimization of CO2 and Pollutant Emissions

Individual Cylinder Combustion Optimization to Improve Performance and Fuel Consumption of a Small Turbocharged SI Engine

Contact Info

Product

Resources

About