Direct Numerical Simulation of Oxygen Transfer at the Air-Water Interface in a Convective Flow Environment and Comparison to Experiments

Two-dimensional Direct Numerical Simulation (DNS) of high Schmidt number mass transfer in a convective flow environment (Rayleigh-B'enard) is carried out and results are compared to experimental data. A fourth-order accurate WENO-scheme has been used for scalar transport in order to aim for a high accuracy in areas of high concentration gradients. It was found that the typical spatial distance between downward plumes of cold high concentration water and the eddy size are in good agreement with experiments using a combined PIV-LIF technique for simultaneous and spatially synoptic measurements of 2D velocity and concentration fields.

Authors:

• B. Kubrak J. Wissink H. Herlina

Keywords:

• Air-Water Interface
• DNS
• Gas Transfer
• LIF.

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