Validation of the LES approach in Kiva‐3V on a square duct geometry

Abstract

SUMMARYThe LES approach implemented in the Kiva-3V code is evaluated on the fully developed flow through a rectangular duct of square cross section. The Reynolds number based on the bulk velocity and duct width is 8000. The number of grid nodes is 96000. Three subgrid scale models are compared: the Smagorinsky, the WALE and the Vreman model. The results differ mainly in the predicted shear stress levels. The Smagorinsky model shows a large overprediction of the shear at the walls, whereas both the WALE and Vreman models perform better due to a reduced contribution of the subgriddissipation. In this study the WALE model gives the best results on simulating the secondary flows and turbulence statistics.

Supersonic Corner Flow Predictions using the Quadratic Constitutive Relation

“…Xu and Pollard 16 investigated a square annular duct using LES and reported that the secondary flow counter rotating vortex pair was predicted symmetrically around the convex 90 degree corner along with a weaker counter rotating vortex pair symmetrically located in the concave 90 degree corner. Huijnen et al 17 investigated the effect of subgrid scale models in LES calculations of a square duct. They concluded that the Smagorinsky model significantly over-predicted shear at wall, which negatively influenced the prediction of secondary flow.…”

“…[12][13][14][15][16][17][18] While DNS captures all motions contained in the flow, and is thus recognized as the most precise simulation method available for turbulent flows, it is extremely computationally expensive. As such, it is only used for very low Reynolds numbers and makes some assumptions about the state of the turbulent flow.…”

Large Eddy Simulation of Premixed Combustion in Spark Ignited Engines Using a Dynamic Flame Surface Density Model

“…In particular, studies devoted to internal combustion (IC) engine simulations using LES is very limited. Studies [1][2][3][4][5] may be identified as some of the promising cold flow simulations which reveal the potential of LES predictions. Remarkably, compared to RANS, overall predictions of these simulations have found to be much better in agreement with experimental results.…”

Assessment of large-eddy simulation feasibility in modelling the unsteady diesel fuel injection and mixing in a highspeed direct-injection engine

“…In the community of engine flow and combustion, the KIVA-3V code [10] represents the state-of-the-art CFD tool for numerical simulations of flows of industrial relevance. In an effort towards LES of engine flow and combustion of practical importance, a LES code based on the wellestablished KIVA-3V package was developed and transient gas jets and liquid sprays were simulated with promising results for flows in a constantvolume chamber [11], among other similar efforts by Huijnen et al [12], Smith et al [13], and Sone et al [1]. However, the LES solver needs to be further assessed in an engine flow environment.…”