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If using the 3TL option, the user must specify the momentum solution option (ISCDMA) of Upwind, Central, and Upwind following the MOM . Upwind Difference is the recommended momentum advection scheme. There are other schemes Central Difference and Experimental Upwind Difference (ISCDMA>2) that are experimental, not fully tested and not currently recommended to be used. The Trapezoidal Correction Scheme is typically set from 3 to 5, and 4 by default.
The 2TL solution is the most robust solution technique and is recommended.
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Figure 1 Numerical Solution Options for 3 Time Level Solution.