Bedform dynamics from coupled bed-flow direct numerical simulations

¹ School of Engineering, Lebanese American University, Byblos, Lebanon
² Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, USA
³ ExxonMobil Upstream Research Company, Houston, TX, USA

^* Corresponding author: nadim.zgheib@lau.edu.lb

Abstract

We present results of time-evolving coupled direct numerical simulations between an erodible bed and an overlying pressure-driven, turbulent flow field. A total of 6 simulations are considered, the details of which are shown in Table 1. The numerical setup consists of a horizontally periodic open channel, and the simulations are run at a shear Reynolds number of Re_τ = 180. The coupling between the spatially and temporally evolving sediment bed and the flow field is enforced through the explicit immersed boundary method (IBM) of Uhlmann [1]. The flow field is fully resolved and is obtained by integrating the conservation of mass and momentum equations using a pseudo spectral code [2]. On the other hand, the sediment bed is modelled via the Exner equation [3]. Details about the numerical approach are available in [4-5].