E4: Design Protection against Climate

Calcullation can be done as follows:

Permeability coefficient: P

Area on surface: A

Time: t

Vapour pressure on both sides: p_i and p_o

Film thickness: l 

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Permeability coefficient, P, is dependent of:

Constant: P₀

Activating energy: E_d

Gas constant: R = 0,0821 l*bar/mol*^oK

Temperature in ^oK(=^oC+273): T

Constant: k₁

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In case of films with several different layers you calculate:

Laminate thickness: L

Layer thickness in layer n: X_n

Total permiability: PPermiability in layer n: P_n