Nomenclature

h ( t , x )

height of thin fluid film

w ( t )

half-width of thin fluid film

p ( t , x , z )

fluid pressure in thin fluid film

Re

Reynolds number of thin fluid film flow

v n ( t , x )

fluid injection/leak-off velocity

V ( t )

total volume of thin fluid film per unit breadth

X

Lie point symmetry

η

x / w ( t ) , scaled similarity variable

z *

z / h ( t ,0 ) , scaled similarity variable

f ( η )

invariant solution for h ( t , x )

g ( η )

invariant solution for v n ( t , x )

β

constant of proportionality in equation g ( η ) = β f ( η )

α

c 4 c 2 where c 4 and c 2 are constants in the Lie point symmetry

ε ( t )

h ( t ,0 ) / w ( t ) , thin fluid film ratio

ψ ( t , x , z )

stream function