JavaFoil Quick Reference Card

Symbol Description Unit
lowercase characters
a speed of sound m/s
c chord length m
x x coordinate m
f (maximum) camber m
xf xposition of maximum camber m
r roughness factor (0...3) -
t (maximum ) thickness m
xt xposition of maximum thickness m
uppercase characters
D drag force N
L lift force N
M pitching moment Nm
M0.25 pitching moment at 25% chord point Nm
S reference area m2
T. transition laminar-turbulent -
S. turbulent separation -
U. upper surface -
L. lowersurface -
greek characters
a alfa angle of attack
d delta flap deflection (downward = positive)
delta_1 displacement thickness of boundary layer m
delta_2 momentum thickness of boundary layer m
delta_3 energy thickness of boundary layer m
rho density of fluid kg/m3
v kinematic viscosity of fluid m2/s
Symbol Description Unit
derived values and coefficients
lift coefficient

drag coefficient

moment coefficient (rel. c/4)

local skin friction coefficient

glide ratio

L/D = Cl/Cd

aerodynamic center

center of pressure

pressure coefficient

critical pressure coefficient (Cp < Cp* indicates supersonic flow)
Re Reynolds number -
M Mach number -
Mcr critical Mach number (flight at M > Mcr leads to supersonic flow) -
local Reynolds number, based on displacement thickness
local Reynolds number, based on momentum thickness
shape factor of boundary layer

H12 = delta_1 / delta_2

shape factor of boundary layer

H32 = delta_3 / delta_2

y1 height of first cell for y+=1 (useful for grid generation) -


Last modification of this page: 21.05.18

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