Sun wind water earth life living legends for design AR2U070 Territory design 5ECTS AR0112 Civil engi

1
Sun wind water earth life living legends for
designAR2U070 Territory (design) 5ECTSAR0112
Civil engineering for dummies (calculations) 2ECTS

• Prof.dr.ir. Taeke M. de Jong
• Prof.dr.ir. C. van den Akker
• Ir. D. de Bruin
• Drs. M.J. Moens
• Prof.dr.ir. C.M. Steenbergen
• Ir. M.W.M. van den Toorn
• http//team.bk.tudelft.nl/ gteducation

2
Publish on your website

• AR1U010
• how you could take wind and noise into account in
  your
• earlier,
• actual and
• future work.

AR0112 calculation and observations of wind or
noise in any location and your design, check your
observations.
As soon as you are ready with all subjects (Sun,
Wind, Water, Earth, Life, Living, Traffic,
Legends), send a message mailtoM.E.Wenmeekers-Tho
mas_at_bk.tudelft.nl referring your web adress,
student number and code AR1U010 or AR0112.
3
Mass of atmosphere
500km air above 1m2that is 10 000kg At earths
surface it equals approx.10m x 1m2 10m3 water
4
Air density and pressure
Density decreases from ample 1kg to 1g/m3 at 50km
height. So, aeroplanes meet less resistance the
higher they fly (until 20km), but propellers and
wings will work less as well.
5
Temperature(height)
Ionosphere
Ionosphere
Troposphere
Mesosphere
Stratosphere
Troposphere
Weather takes place in troposphere.
6
Clouds
Expanding (cooling) air bubbles stop raising as
soon as their temperature equals their
environment, sometimes loosing moist as rain.
7
Wind
8
Wind force(velocity2)
length velocity time
volume surface length
volume surface velocity time
force mass acceleration
mass density volume
acceleration velocity / time
force density surface velocity time
velocity / time
force density surface velocity2
9
Wind force

• force density surface velocity2

Velocity occurs two times in the formula for wind
force, so force increases parabolically by the
square of velocity.
10
Wind energy
Velocity occurs three times in the formula for
wind energy, so energy increases by the third
power of velocity.

• force density surface velocity2

energy force length
length velocity time
energy density surface velocity3 time
11
Effective energyfrom a wind turbine
energy density surface velocity3 time
density 1.29 kg/m3
surface p 102 314 m2
velocity 5.4 m/sec
time year 60 60 24 365 sec
efficiency 19
effective energy 1.29 314 5.43 year 19
12119Wa
12
Impact radius of wind measures

• Measures can be taken on the level of
• national choice of location (R100km)
• regional choice of location (R 30 km)
• arrangement of rural areas form of conurbations
  (R 10 km)
• local choice of location (R 10 km)
• form of town and town edge (R 3 km)
• lay-out of districts and district quarters (R 1
  km)
• allotment of neighbourhoods and neighbourhood
  quarters (R 300 m)
• allotment, urban details and ensembles divided in
  4 hectares (R 100 m)
• buildings (R 30m), and
• the micro climate, important for humans, plants
  and animals (R 10m).

13
Roughness classes
1
5
6
2
3
7
8
4
14
Wind velocity
15
Power, dispersion, comfort
16
Measuring year average potential wind velocity
17
Measuring wind

• Wind stations register gusts of more than 5
  seconds duration.
• All measurements are averaged for one
  hourresulting in the hour average wind
  velocity.
• From these hour averages a year average can be
  calculated, theyear average wind velocity.

18
Standard wind

• Obstacles around the wind station introduce a
  deviation by which these data are not immediately
  applicable in other locations of that regio.
• Correction into a standard ground roughness 3
  (grass land) and a standard height of 10 metre
  produces the year average potential wind
  velocity.
• From that year average potential wind velocity
  one can calculate back the year average wind
  velocity of neighbouring locations on different
  heights and roughness using local ground data
  (roughness classes).

19
Data lost in the average

• However, in the year average wind velocity some
  data are lost relevant for energy use, potential
  energy profit, dispersion of air pollution and
  comfort of outdoor space as impact of different
  wind velocities.
• Firstly we miss a specification of wind direction
  and a statistical distribution into different
  wind velocities throughout the year.
• Secondly we miss how often special velocities
  occur.
• So, we have to go back to the sources of
  distributive frequency division of the hour
  average wind velocity per wind direction, reduced
  to 10 metre height above open ground per wind
  station.

20
Mea-sure-ments
21
Modelling wind velocity
22
Modelling data for calculations

• Fortunately the form of the graphs is higly
  similar to the mathematical graph of a Weilbull
  probability. 

C determines form, a scale and wind
direction differs per region
23
The impact of parameters
24
Power of wind turbine
25
Ventilation losses
26
Loss Schiphol and Eindhoven
27
Comfort
28
Air pollution
29
Regional behaviour
30
Windvelocity 20m height
31
Roughness islands
32
Lateral impacts
33
Dispersion
34
Lobe city
35
Lobe city
36
Temperature impact
37
Lower levels of scale
38
Wind tunnel experiments
Low rise at the edge
High rise at the edge
39
Green central or perpheral
Peripheral green
Central green
40
District level
Average ventilation loss of a non airtight
dwelling in kWh per allotment direction if
standard Northerly wind would blow from all
directions .
Average DCp(10) in different configurations two
times mirrored around the centre.
peripheral low riseperipheral high
riseperipheral green lowcentral green low
41
Low and high rise on the edge
42
Green peripheral or central
43
Neighbourhoods and trees
Measure points 1(186kWh), 6(190kWh), 7(190kWh),
9(163kWh), 15(197kWh) and 32(182kWh) score high
by wind over a 40m neighbourhood road without
trees. Measure points 5(145kWh), 17(143kWh) and
29(150kWh) get wind over a much wider district
road (80 to 100m) with 6m heigh trees. The local
importance of trees in large urban spaces is
indicated here. The difference is approx. 40 or
virtually 1500kWh.
44
Neighbourhoods and trees

• In configuration 2 measure points 7(147kWh),
  11(170kWh) en 14(131kWh) lie on a 40m wide
  neighbourhood road without trees. Measure point
  14 scores low because it is shelterd by 22m high
  high rise buildings on the other side of the
  road. The low rise minimum measure point
  10(116kWh) lies on 10m wide ensemble streets. The
  maximum in measure point 25(180kWh) is most
  likely explained by its position on the edge of
  the used model.

45
Neighbourhoods and trees
In configuration 3 here not visible measure point
27(150kWh) lies on a 40m wide neighbourhood road
without trees. Measure points 18(152kWh),
15(150kWh) and 16(143kWh) score approximately
equaly high lying on a 70m wide district road
with trees. Minima 17(116kWh) and 19(116kWh) get
wind from a backyard lying on 10m wide ensemlbe
roads.
46
Neighbourhoods and trees
In configuration 4 measure point 18(194kWh)
scores extremely high. It gets wind from 300m
wide open green area in the centre of district
quarter. Even district road trees do not help
much on this location. Measure point 19(143kWh)
lies on a small street, but that is the first
street behind the green behind measure point
18(194kWh), and that is still apparent there.
47
Repeating hectare allotments
point
line
angle
court
48
Court and high rise allotments
49
Point and line allotments
50
Building level
51
Vibration in the air

• Movement of air is measured as wind when it is
  moving into one direction longer than 5 seconds.
  When it is flowing back in the next 5 seconds it
  is not even counted in wind statistics.
• It would have a vibration time of 5 sec with a
  frequency f of 1/5 0.2 vibrations per second or
  0.2Hz (hertz).

52
Sound

• Vibrations in the air from 16 Hz (vibrations per
  second) to 20 000 Hz are accepted by our eardrums
  as sound.
• Vibrations slower then 16Hz are called
  infrasonic, faster then 20 000Hz ultrasonic.

53
Notes
Any next octave doubles the frequency. An octave
is subdivided in 12 notes (named a, ais or bes,
b, c, cis or des, d, dis or es, e, f, fis or ges,
g, gis). Because 21/12 1.0594630944, the
frequency of any next key is a factor
1.0594630944 higher then the previous one. So you
can calculate the frequency of any note (n087)
by f(n)27.5 x 1.0594630944n.
54
Notes and Octaves
55
Harmonic Intervals
56
Music notes, intervals
57
Scales
58
Span of music
59
Overtones
60
Added amplitudes
61
Supposition of tones
62
From sound to noise
63
Amplitude and power of sound
64
Power/m2

• The power/m2 of a sound wave (called intensity
  I and expressed in W/m2) depends on amplitude
  A, frequency f, air density r (normally
  1.290kg/m3), and travel speed c (normally
  340m/sec) according to I  r x (2 x p x f x A)2 x 
  c/2.
• So, in normal r and c conditions power depends on
  amplitude A and frequency f according to
  I  8658 x (f x A)2.

65
Distance

• A speaking voice produces 10-5 W.
• A globe with a radius of 28cm has a surface of
  1m2.
• So, at 28cm distance that voice has a power of
  10-5 W/m2.
• It is composed by adding 8658(f x A)2 for every
  frequency and its accompanying amplitude in the
  voice.
• A piano produces maximally 0.2W/m2 and if it
  would be produced by tone c only the amplitude
  should be 0.0000367m.
• For an exended symphony orchestra and a
  loudspeaker the figures would be 5W/m2
  (A0.0000183m) and 100W/m2 (A0.00082m).

66
Intensity(frequency, amplitude)
67
Intensity (W/m2) and dB

• A logarithmical representation shows the range
  from soft to loud better.
• Dividing the intensity by a standard of 10-12
  W/m2 (comparing it with that standard) we get
  positive logarithms from 0 to 14 only, starting
  with what is just audible.
• Multipying it by 10 we get a useful range of
  decibells (dB) from 0 to 150.

68
From intensity to dB
69
Audibility
70
dB(A) what we think to hear
71
From dB to dB(A)
72
Traffic noise
73
Traffic