Table 1 Configuration of the flows over hypothetical urban areas in wind tunnel experiments and LES

AR (= h/b)

1/2

1/4

1/8

1/12

1

1/2

1/3

1/5

1/11

Rib [×10³ m]

 h

19

1

 b

38

76

152

228

1

2

3

5

11

δ [m]

0.240

0.245

0.260

0.265

0.285

0.265

0.260

11

δ/h

12.6

12.9

13.7

14.0

15.0

14.0

13.7

11

U_∞ [m s⁻¹]

3.28

6.66

3.31

6.61

3.28

6.70

3.29

6.60

1.01

0.81

0.65

0.58

0.56

U_m [m s⁻¹]

2.92

5.91

2.99

5.95

2.84

5.88

2.91

5.85

0.86

0.66

0.51

0.43

0.41

u_τ [m s⁻¹]

0.18

0.38

0.22

0.45

0.22

0.47

0.22

0.47

0.047

u_τ/U_∞ [×10⁻³]

56

57

65

68

68

71

68

71

0.046

0.058

0.072

0.081

0.085

u_τ/U_m [×10⁻³]

63

65

72

76

78

81

77

80

0.055

0.071

0.092

0.11

0.11

f [×10⁻³] (= 2u ² _τ /U ²_∞ )

8.0

8.3

10.4

11.4

12.2

13.0

11.9

12.8

4.3

6.7

10.3

13.2

14.3

Re_δ [×10³] (= U_∞δ/ν)

79

163

86

175

93

191

87

172

111

89

72

63

61

Re_h [×10³] (= U_∞h/ν)

6

13

6

13

6

13

6

13

10

8

7

6

6

Re_m [×10³] (= U_mh/ν)

6

11

6

11

5

11

6

11

9

7

5

4

4

Re_τ (= u_τh/ν)

350

726

409

854

422

900

426

889

469