eTheses Repository - University of Birmingham

epresenting suburban development a mean building height of 10 m is considered
reasonable, since this represents an average of a typical European city height of 15 m (Ratti
et al. 2001) and that for a suburban area such as Guildford, UK (Oestges et al. 1999).
Table 3.5: Distribution of building heights for the two urban classes defined for the simulations
representing London
Percentage of buildings
Building height (m) Urban class 1 Urban class 2
5 20
10 10 60
15 25 20
20 35
25 25
30 10
35
40 10
45
50 5
Average height (m) 23 10
The values used for the thermal characteristics of the buildings for both the idealised
simulations and the London simulations were taken from the literature (Martilli et al. 2002)
and are summarised in Table 3.6.
Table 3.6: Parameters for the city for the urban simulation. κs is the thermal diffusivity of the material,
C s is the specific heat of the material, T int is the initial temperature of the material (equal to the
temperature of the deepest layer), ε is the surface emissivity, α is the albedo and z 0 is the roughness
length of the surface.
Surface κs (m 2 s -1 ) Cs (J m -3 K -1 ) Tint (K) ε α z0 (m)
Wall (urban) 0.57 * 10 -6
Roof (urban)
0.62 *10 -6
Floor (urban) 0.47 * 10 -6
1.54 *10 6
1.5 * 10 6
1.74 * 10 6
293 0.9 0.2 n/a
293 0.95 0.2 0.01
290 0.9 0.2 0.01
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