Patankar teaches the control-volume method instead of strictly mathematical finite differences. This approach ensures total conservation of mass, momentum, and energy across any grid size. Every term in the discretization equation corresponds to a physical flux. The SIMPLE Algorithm

Patankar heavily emphasizes that the linearized source term must satisfy

A crucial trick for ensuring numerical stability and convergence. Finding the Best Solution Manual

Patankar later introduced SIMPLER (SIMPLE Revised) in 1979 to improve convergence rates and robustness. Key Discretization Schemes

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