Flat-Plate Skin-Friction Drag

Compute flat-plate Reynolds number, laminar/turbulent/mixed Cf, and skin-friction drag with a boundary-layer sketch.

visual calculatorAerodynamics & External Flow

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.

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skin frictionflat plateboundary layerdrag

formula

KaTeX rendered

\begin{aligned}\text{C\_f,lam = 1.328/sqrt(Re\_L)}\\[0.35em]\text{C\_f,mixed \~{}= 0.074/Re\_L\^{}(1/5) - 1742/Re\_L}\end{aligned}

ASCII source

C_f,lam = 1.328/sqrt(Re_L), C_f,mixed ~= 0.074/Re_L^(1/5) - 1742/Re_L

U_inf (m/s)plate length (m)plate width (m)rho (kg/m^3)nu (m^2/s)

Re_L

2.800e+6

C_f laminar

0.00079

C_f turbulent

0.00380

C_f mixed

0.00318

skin-friction drag (N)

1.1446

Mixed turbulent estimate uses the common smooth flat-plate correction with transition near Re_x = 5e5.

skin friction flat plate boundary layer drag