Towards LES of High Reynolds Number External Flows on Unstructured Grids
نویسندگان
چکیده
Large eddy simulation (LES) using the dynamic Smagorinsky model (DSM) (Germano et al., 1991) and discretely kinetic energy conserving numerical methods (Mahesh et al., 2004) has successfully predicted complex flows such as gas turbine combustors and marine propulsor crashback (e.g. Vyšohlid and Mahesh (2005); Chang et al. (2008); Jang and Mahesh (2010, 2012); Verma et al. (2012)). This paper discusses two developments towards reliably using LES for inhomogeneous and attached flows: (1) a dynamic Lagrangian model where a dynamic procedure is proposed for the Lagangian timescale and (2) a wall model where in addition to the Germano-identity error, external Reynolds stress is also imposed as a constraint on the ensemble-average subgrid-scale stress. Both developments are for unstructured grids.
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