Modeling on Spray-Wall Interaction for Direct Gasoline Injection Engines

健, 松田; 二郎, 千田

doi:10.1299/kikaib.69.2698

Cited by 5 publications

(2 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This modelling approach has been furthered by a number of researchers including that of Rosa et al 26 and the works of Senda and colleagues. [20][21][22][23][24] The impingement model used in this study is primarily based on the works by Senda et al but also incorporates many of the features of the model by Bai and Gosman and Rosa et al This modelling approach provides a significant reduction in the number of userdefined constants which is beneficial with limited experimental data for model validation.…”

Section: Droplet-wall Interaction Modellingmentioning

confidence: 99%

“…At low Weber numbers, three film break-up subregimes are defined from the experimental works of Al-Roub and colleagues 33,34 as a function of the non-dimensional film thickness (d) and consequently define the child droplet diameter ratio and Weber number: 20 Rim type: break-up or droplet ejection of one of a few droplets at the outer edge of the film; Cluster type: break up into clusters of many small droplets; 16 with addition sub-models for algorithm speed up, 17 automatic coalescence time step adjustment 18 and additional geometric constraints 19 (K rm = 1) Droplet-wall interaction model Senda and colleagues, [20][21][22][23][24] Bai and Gosman 25 and Rosa et al 26 (c f = 0.7) Leidenfrost temperature determination Habchi 27 and Spiegler et al 28…”

Section: Droplet-wall Interaction Modellingmentioning

confidence: 99%

See 1 more Smart Citation

Impingement characteristics of an early injection gasoline direct injection engine: A numerical study

Beavis

Ibrahim

Malalasekera

2016

International Journal of Engine Research

View full text Add to dashboard Cite

This paper describes the use of a Lagrangian discrete droplet model to evaluate the liquid fuel impingement characteristics on the internal surfaces of an early injection gasoline direct injection (GDI) engine. The study focuses on fuel impingement on the intake valve and cylinder liner between start of injection (SOI) and 20° after SOI using both a single-and multi-component fuel. The single-component fuel used was isooctane and the multi-component fuel contained fractions of iso-pentane, iso-octane and n-decane to represent the light, medium and heavy fuel fractions of gasoline, respectively. A detailed description of the impingement and liquid film modelling approach is also provided. 2Fuel properties, wall surface temperature and droplet Weber number and Laplace number were used to quantify the impingement regime for different fuel fractions and correlated well with the predicted onset of liquid film formation. Evidence of film stripping was seen from the liquid film formed on the side of the intake valve head with subsequent ejected droplets being a likely source of unburned hydrocarbons and particulate matter emissions. Differences in impingement location and subsequent location of liquid film formation were also observed between single-and multicomponent fuels. A qualitative comparison with experimental cylinder liner impingement data showed the model to well predict the timing and positioning of the liner fuel impingement.

show abstract

Section: Droplet-wall Interaction Modellingmentioning

confidence: 99%

Section: Droplet-wall Interaction Modellingmentioning

confidence: 99%

Impingement characteristics of an early injection gasoline direct injection engine: A numerical study

Beavis

Ibrahim

Malalasekera

2016

International Journal of Engine Research

View full text Add to dashboard Cite

show abstract

Numerical Evaluation of Combustion Regimes in a GDI Engine

Beavis

Ibrahim

Malalasekera

2018

Flow Turbulence Combust

View full text Add to dashboard Cite

There is significant interest in the gasoline direct-injection engine due to its potential for improvements in fuel consumption but it still remains an area of active research due to a number of challenges including the effect of cycle-by-cycle variations. The current paper presents the use of a 3D-CFD model using both the RANS and LES turbulence modelling approaches, and a Lagrangian DDM to model an early fuel injection event, to evaluate the regimes of combustion in a gasoline direct-injection engine. The velocity fluctuations were investigated as an average value across the cylinder and in the region between the spark plug electrodes. The velocity fluctuations near the spark plug electrodes were seen to be of lower magnitude than the globally averaged fluctuations but exhibited higher levels of cyclic variation due to the influence of the spark plug electrode and the pent-roof geometry on the in-cylinder flow field. Differences in the predicted flame structure due to differences in the predicted velocity fluctuations between RANS and LES modelling approaches were seen as a consequence of the inherently higher dissipation levels present in the RANS methodology. The increased cyclic variation in velocity fluctuations near the spark plug electrodes in the LES predictions suggested significant variation in the relative strength of the incylinder turbulence and that may subsequently result in a thickening of the propagating flame front from cycle-to-cycle in this region. Throughout this paper, the numerical results were validated against published experimental data of the same engine geometry under investigation.

show abstract

Effects of Fuel-Induced Piston-Cooling and Fuel Formulation on the Formation of Fuel Deposits and Mixture Stratification in a GDI Engine

Giovannoni

D'Adamo

Cicalese³

et al. 2015

SAE Technical Paper Series

View full text Add to dashboard Cite

Fuel deposits in DISI engines promote unburnt hydrocarbon and soot formation: due to the increasingly stringent emission regulations (EU6 and forthcoming), it is necessary to deeply analyze and well-understand the complex physical mechanisms promoting fuel deposit formation. The task is not trivial, due to the coexistence of mutually interacting factors, such as complex moving geometries, influencing both impact angle and velocity, and time-dependent wall temperatures. The experimental characterization of actual engine conditions on transparent combustion chambers is limited to highly specialized research laboratories; therefore, 3D-CFD simulations can be a fundamental tool to investigate and understand the complex interplay of all the mentioned factors. The aim is pursued in this study by means of full-cycle simulations accounting for instantaneous fuel/piston thermal interaction and actual fuel characteristics. To overcome the standard practice, based on the adoption of time-independent wall temperatures, solid cell layers are added onto the piston crown. In particular, thermal boundary conditions on the lower face of the piston portion are derived from a complete CHT simulation, thus considering both the actual piston shape and the point-wise cooling effect by the oil jets, the friction contribution and the heat transfer to the cylinder liner and the connecting rod. Furthermore, the use of a simplified fuel model based on a single-component formulation is compared to a more realistic hydrocarbon blend. The methodology is applied to a currently produced turbocharged DISI engine operating at full load peak power and maximum torque regimes; the piston thermal field is completely resolved in space and time during the engine cycle, and its effects on spray guidance, fuel impingement and liquid film formation are carefully analyzed

show abstract

Modeling on Spray-Wall Interaction for Direct Gasoline Injection Engines

Cited by 5 publications

References 2 publications

Impingement characteristics of an early injection gasoline direct injection engine: A numerical study

Impingement characteristics of an early injection gasoline direct injection engine: A numerical study

Numerical Evaluation of Combustion Regimes in a GDI Engine

Effects of Fuel-Induced Piston-Cooling and Fuel Formulation on the Formation of Fuel Deposits and Mixture Stratification in a GDI Engine

Contact Info

Product

Resources

About