Detached eddy simulation of cyclic large scale fluctuations in a simplified engine setup

Hasse, Christian; Sohm, Volker; Durst, Bodo

doi:10.1016/j.ijheatfluidflow.2008.10.001

Cited by 48 publications

(45 citation statements)

References 16 publications

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“…Before 100 • CA, an accurate tumble identification is not possible since the large-scale tumble structure is too weak. As expected, significant CCV of the tumble center occur, which is also known as PVC and was also identified in previous investigations [4,7,8]. Especially close to the symmetry plane, a significant movement of the tumble center can be observed during the entire intake stroke and even in the phase when the piston remains in its lowest position.…”

Section: Tumble Generationsupporting

confidence: 86%

“…Borée et al [7] analyzed the generation of the tumbling motion using particle image velocimetry (PIV). One of the major findings was the existence of a precessing vortex core (PVC), which was also observed in a numerical study by Hasse et al [8]. Wang et al [9] investigated and quantified the variation of the tumble center depending on the valve lift.…”

Section: Introductionmentioning

confidence: 71%

“…To minimize numerical diffusion, a central differencing scheme is used in space and a second-order backward scheme in time. The solver's suitability for SRS in IC engines has been shown in previous works [6,8,11,21,28].…”

Section: Numerical Setupmentioning

confidence: 81%

See 2 more Smart Citations

A Combined Numerical and Experimental Study of the 3D Tumble Structure and Piston Boundary Layer Development During the Intake Stroke of a Gasoline Engine

Buhl

Gleiss

Köhler

et al. 2016

Flow Turbulence Combust

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Due to its positive effect on flame propagation in the case of a well-defined breakdown, the formation of a large-scale tumble motion is an important goal in engine development. Cycle-to-cycle variations (CCV) in the tumble position and strength however lead to a fluctuating tumble breakdown in space and time and therefore to combustion variations, indicated by CCV of the peak pressure. This work aims at a detailed investigation of the large-scale tumble motion and its interaction with the piston boundary layer during the intake stroke in a state-of-the-art gasoline engine. To allow the validation of the flow near the piston surface obtained by simulation, a new measurement technique called "Flying PIV" is applied. A detailed comparison between experimental and simulation results is carried out as well as an analysis of the obtained flow field. The large-scale tumble motion is investigated based on numerical data of multiple highly resolved intake strokes obtained using scale-resolving simulations. A method to detect the tumble center position within a 3D flow field, as an extension of previously developed 2D and 3D algorithms, is presented and applied. It is then used to investigate the phase-averaged tumble structure, its characteristics in terms of angular velocity and the CCV between the individual intake strokes. Finally, an analysis is presented of the piston boundary layer and how it is influenced by the tumble motion during the final phase of the intake stroke.

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Section: Tumble Generationsupporting

confidence: 86%

Section: Introductionmentioning

confidence: 71%

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A Combined Numerical and Experimental Study of the 3D Tumble Structure and Piston Boundary Layer Development During the Intake Stroke of a Gasoline Engine

Buhl

Gleiss

Köhler

et al. 2016

Flow Turbulence Combust

View full text Add to dashboard Cite

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“…Since decades, engine researchers have been trying to understand the basis of these processes from different points of view: theoretical, experimental and computational. Computational tools, such as computational fluid dynamics (CFD) simulations, have proved their great potential [2], [3] and are growing and improving every day as proved by the use of new and models able to provide more detailed data such Deatached Eddy Simulation [4] or Large Eddy Simulation [5]. Still, these models are not completely predictive and experimental data are necessary at least for validation, but also to correctly define the boundary conditions of the problem.…”

Section: Introductionmentioning

confidence: 99%

Experimental characterization of diesel ignition and lift-off length using a single-hole ECN injector

Benajes

Payri

Bardi

et al. 2013

Applied Thermal Engineering

150

126

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“…The use of the one equation SA model, allows to save computational resources when complex three-dimensional domains are considered and also offers the possibility to switch to a Detached Eddy Simulation (DES) scheme. The DES option attempts to combine the best features of RANS and LES (Viswanathan and Tafti, 2006;Hasse et al, 2009;Paik et al, 2009), and represents a future development of this work. Such a hybrid approach reduces to RANS near solid boundaries and to LES away from the wall and is very promising for fully three-dimensional studies of pollutants dispersion modelling in urban areas.…”

Section: Numerical Modelling Of Ufps Distribution Inside Street Canyonsmentioning

confidence: 99%

Numerical Simulation of Ultrafine Particle Dispersion in Urban Street Canyons with the Spalart-Allmaras Turbulence Model

Scungio

Arpino

Stabile

et al. 2013

Aerosol Air Qual. Res.

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The increased traffic emissions and reduced ventilation of urban street canyons lead to the formation of high particle concentrations as a function of the related flow field and geometry. In this context, the use of advanced modelling tools, able to evaluate particle concentration under different traffic and meteorological conditions, may be helpful.In this work, a numerical scheme based on the non-commercial fully explicit AC-CBS algorithm, and the one-equation Spalart-Allmaras turbulence model, was developed to perform numerical simulations of fluid flow and ultrafine particle dispersion in different street canyon configurations and under different wind speed and traffic conditions. The proposed non-commercial numerical tool was validated through a comparison with data drawn from the scientific literature.The results obtained from ultrafine particle concentration simulations show that as the building height increases the dispersion of particles in the canyon becomes weaker, due to the restricted interaction between the flow field in the street canyon and the undisturbed flow. Higher values of approaching wind speed facilitate the dispersion of the particles. The traffic effect has been evaluated by imposing different values of particles emission, depending on the vehicles type, with the lowest concentration values obtained for the Euro 6 vehicles, and the highest for High Duty Vehicles. A parametric analysis was also performed concerning the exposure to particles of pedestrians in different positions at the road level as a function of street canyon geometry, traffic mode, and wind speed. The worst exposure (1.25 × 10 6 part./cm 3 ) was found at the leeward side for an aspect ratio H/W = 1, wind speed of 5 m/s when High Duty Vehicles traffic was considered.

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Detached eddy simulation of cyclic large scale fluctuations in a simplified engine setup

Cited by 48 publications

References 16 publications

A Combined Numerical and Experimental Study of the 3D Tumble Structure and Piston Boundary Layer Development During the Intake Stroke of a Gasoline Engine

A Combined Numerical and Experimental Study of the 3D Tumble Structure and Piston Boundary Layer Development During the Intake Stroke of a Gasoline Engine

Experimental characterization of diesel ignition and lift-off length using a single-hole ECN injector

Numerical Simulation of Ultrafine Particle Dispersion in Urban Street Canyons with the Spalart-Allmaras Turbulence Model

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