Pace V - 16 
Ventilation Design Handbook on Animal Research Facilities Using Static Microisolators 
5 . 2 . 2.1 
k-e turbulence model 
This turbulence model calculates two variables; the kinetic energy of turbulence (k) and the 
dissipation rate of k (denoted e). 
The eddy viscosity is defined from dimensional analysis as: 
Hr = C uP— 
( 5 . 10 ) 
The transport equations for k and e are: 
dpU t k _ d (( 
dx. dx. 
p + 
'k 
dx 
+ P + G - p£ 
i / 
( 5 . 11 ) 
dpU £ d (' 
dx . dx- 
p + 
Pr 
A de A 
dx . 
e / i / 
+ C,|(P + C,G)-C 2 p^- 
( 5 . 12 ) 
where P is the shear production, defined as: 
dU , 
dU . du t 
y dxj + chc, 
( 5 . 13 ) 
G is the production of turbulence kinetic energy due to buoyancy, and is given by: 
G = -Pgi^- 
Or <7X, 
( 5 . 14 ) 
0.09 
Cl 
1.44 
c 2 
1.92 
C 3 
1.0 
<Jk 
1.0 
<T e 
1.217 
