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Lecture 13: Advanced Time-Variable Solutions. CE 498/698 and ERS 685 Principles of Water Quality Modeling. Lecture 13. Advanced time-variable solutions Implicit approaches. >1 unknown in ea. eqn. Explicit approaches. only 1 unknown in ea. eqn. derivation of methods not covered in
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Lecture 13: Advanced Time-Variable Solutions CE 498/698 and ERS 685 Principles of Water Quality Modeling Lecture 13
Lecture 13 • Advanced time-variable solutions • Implicit approaches >1 unknown in ea. eqn. • Explicit approaches only 1 unknown in ea. eqn. Lecture 13
derivation of methods not covered in this class know for this class Lecture 13 • Advanced time-variable solutions • Implicit approaches • Explicit approaches • Table 13.1 Lecture 13
Numerical dispersion: Stability: FTCS explicit methods FTBS Recall from Lecture 12 Constraints: Finite difference approaches: Lecture 13
Lecture 13 • Explicit method • MacCormack – CTCS • Implicit methods • BTCS • Crank-Nicholson Lecture 13
Method Numerical dispersion Stability Implemen-tation Ease FTBS Easy FTCS Easy MacCormack CTCS None Conditional (more liberal) Moderate error inbook! BTCS Difficult Crank-Nicholson None Difficult Table 13.1 Lecture 13