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The turbulent channel flow database is produced from a direct numerical simulation (DNS) of wall bounded flow with periodic boundary conditions in the longitudinal and transverse directions, and no-slip conditions at the top and bottom walls. In the simulation, the Navier-Stokes equations are solved using a wall {normal, velocity {vorticity formulation. Solutions to the governing equations are provided using a Fourier-Galerkin pseudo-spectral method for the longitudinal and transverse directions and seventh-order Basis-splines (B-splines) collocation method in the wall normal direction. De-aliasing is performed using the 3/2-rule [3]. Temporal integration is performed using a low-storage, third-order Runge-Kutta method. Initially, the flow is driven using a constant volume flux control (imposing a bulk channel mean velocity of U = 1) until stationary conditions are reached. Then the control is changed to a constant applied mean pressure gradient forcing term equivalent to the shear stress resulting from the prior steps. Additional iterations are then performed to further achieve statistical stationarity before outputting fields.
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Transitional Boundary Layer Data Set
Direct numerical simulation (DNS) of a transitional boundary layer over a plate with an elliptical leading edge. Navier-Stokes was discretized on a curvilinear grid and solved using a finite volume DNS code. A fractional-step algorithm was adopted, and the spatial discretization was a staggered volume-flux formulation. The viscous terms were integrated in time implicitly using the Crank-Nicolson and the advections terms were treated explicitly using the Adams-Bashforth. Pressure was treated using implicit Euler in the δp-form. The pressure equation was Fourier transformed in the span, and the resulting Helmholtz equation was solved for every spanwise wavenumber using two-dimensional multi-grid. After the simulation has reached a statistical stationary state, 4701 frames of data, which includes the 3 components of the velocity vector and the pressure, are generated and written in files that can be accessed directly by the database (FileDB system). Since the grid is staggered, data at the wall are not stored in the database. However, JHTDB provides values in the region between the wall and the first grid point, y∈[0, 0.0036], using 4th-order Lagrange polynomial inter- and extrapolation. The y-locations of the grid points in the vertical direction can be downloaded from this text file.
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- Award ID(s):
- 2103874
- PAR ID:
- 10423316
- Publisher / Repository:
- Johns Hopkins Turbulence Databases
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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