$ cd ..
3D Courant Number
Compute directional Courant sum and allowable time step on anisotropic grids.
visual calculatorNumerics & Stability
Read the flow shape before trusting the number.
This page turns a CFD setup into regime, scale, and dominant-effect cues. Adjust the calculator below and compare the moving graphic with the computed result.
01
input scale
02
model
03
check
CourantCFLtime step3D
formula
KaTeX rendered
ASCII source
C = dt (|u_x|/dx + |u_y|/dy + |u_z|/dz)C_x + C_y + C_z
0.5000 stable
dt_max (s)
0.0008
Many finite-volume solvers report max Courant over cells. This local estimate uses a directional sum.