Parameters
Shape
Custom C_D
0.50
Reference Area A
0.500 m²
Fluid
Temperature T
20 °C
Affects density and dynamic viscosity
Velocity v
30.0 m/s
Weight W (for terminal velocity)
10.0 N
—
Drag Force F_D [N]
—
Reynolds No. Re
—
Terminal Vel. v_t [m/s]
—
Drag Power P [W]
Drag Force F_D vs Velocity v
C_D vs Reynolds Number Re (sphere, empirical)
Theory
Drag force equation:
$$F_D = \frac{1}{2} C_D \rho A v^2$$Reynolds number: $Re = \dfrac{\rho v L}{\mu}$
Terminal velocity (drag = weight): $v_t = \sqrt{\dfrac{2W}{C_D \rho A}}$
Drag power: $P = F_D \cdot v$
CAE Note: Pre-CFD hand-calculation for OpenFOAM / ANSYS Fluent aerodynamic simulations. Same form as LS-DYNA fluid–structure interaction (FSI) drag term. Also used for drop-test terminal velocity checks, vehicle fuel-economy drag estimation, and wind tunnel data verification.