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1.
2. INTRODUCTION-1
The sun is the main source of light for the earth, and it is about 150
million Km away from the earth.
The natural light better than the artificial that it has variable
illumination according to the path of the clouds and this changes in
the degree and the color of the light is efficient for the protecting of
the human intelligence and the human health in the contrary of the
constant artificial light which is boring the design of day lighting
inside the building is trying to enter the most quantity of light
without glare.
To avoid glare we must avoid the direct sunrays.
conclude:From this we
1-The general goal for day lighting is the same as that for electric
lighting to supply sufficient quality light while minimizing direct
glare veiling reflections and excessive brightness ratios.
2-the second goal is to reduce or prevent the severe direct glare
of unprotected windows and skylight.
3-the third goal is to prevent excessive brightness ratio especially
those caused by direct sunlight.
4-the fourth goal is to prevent or minimize veiling reflection
especially from skylight and clerestory windows, lighting should not
be too directional because of the dark shadows that result.
5-the fifth goal is to diffuse the light by means of multiple
reflections of the ceiling and walls.
To satisfy the goals some strategies must be addressed at the
earliest moments in the schematic design process, for example
both of the orientation and form of the building are critical to a
successful day lighting scheme.
Basically light finishes are required to increase the distribution.
It is also difficult to shade horizontal glazing. For these reasons it is
often appropriate to use vertical glazing on the roof in the form of
clerestory windows, monitors. or saw tooth arrangements.
3. There are four ways to measuring of daylight in building:
1_coefficent of daylight method.
2_lumen method.
3_artificialdoom method.
4_computer programs method.
4. 2-General data of natural lighting.
Position Materials
Sky light Window wall Clerestory
a-position
Recommended spacing for skylights without windows.
Classification of
openings
5. Recommended spacing for skylights with windows.
Place skylight in front of a north wall for more uniform lighting and
less glare.
Steeply sloped sky lights will perform better by collecting more
winter
Light and less summer light.
The ideal Plan for day lighting as well as general solar control
Has all windows facing north and south
6. While day lighting from windows is limited to the area about 15 feet
From the outside walls, roof openings can yield fairly uniform
lighting
Over unlimited areas
These are the various possibilities for overhead openings for day
lighting.
9. This diagram shows the effect of painting some of the room walls with
the black color on the quantity of light at the point x.
10. 3-Day-lighting Design Factors
Primary Objectives
The report to be published on completion of this
research in August 2001 should assist the reader to:
• Understand the benefits of utilising natural lighting in sports
halls; Appreciate that daylighting can contribute significantly
to the energy efficiency of a sports hall; Appreciate that
daylighting can contribute significantly to the architectural
opportunities of a sports hall; Communicate to clients the
importance of daylighting to running costs savings;
• Appreciate good practice in natural lighting design in general
and in sports halls in particular, and its integration with
artificial lighting and other building services;
• Understand the requirements and constraints of individual
activities and standards of play, in relation to patterns of use,
lighting levels, variations in light quantity, subjective
responses and spatial needs;
• Understand and be able to access the guidance, tools and
techniques available for daylighting design;
• Be capable of making informed decisions to assist in
designing a sports hall that uses daylighting without
detriment to the activities;
• Understand the requirements and constraints of different
design and control strategies, in relation to building operation
and maintenance;
• Work creatively with others disciplines [architect, engineer,
qs and client] in the design process.
Natural daylight can effectively be used to displace the
illumination and energy demands of a conventional
mechanical lighting system during suitable periods of daylight.
The BRE derived simplified DF formula is given as
follows:
11. DF = CG AG θ τ
AIS (1 -ρ ρ 2 )
Where:
DF =Daylight Factor
CG =Glazing obstruction coefficient (dirt or barriers to light
transmission)
AG =Area of glazing
θ =Angle of visible sky
τ =Glazing transmission factor
AIS =Area of internal surfaces
ρ =Area weighted average reflectance of room surfaces
When average daylight factors greater than 5%are
achieved,this indicates effective use of daylight.As a result of
these “high”daylight factors,artificial lighting is mainly used
during periods of night-time/ darkness and for specific tasks
requiring high illuminance.As daylight would be the major
lighting component for this environment,this does not justify
the installation of expensive,complex artificial lighting control
circuitry as financial savings would be considerably smaller
than the capital outlay and installation costs associated with
this type of control.
When average daylight factors between 2%and 5%are
achieved careful consideration should be given to the planned
lighting installation and control strategy to take full advantage
of the daylight when available.
The lighting strategies for these environments require
omprehensive control and can justify the installation of a
complex system.
When average daylight factors are less than 2%,this indicates
that natural day-lighting would not be effective in illuminating
the environment and artificial lighting would be operational for
the majority of the day, therefore care should be taken to
ensure an energy efficient lighting design is developed.
12. Lighting Control:
When incorporating natural daylight within buildings,it is
important that a complimentary active control system is
installed.To maximise energy savings,the control system
should be a proportional system directly linked to the artificial
lighting system so that the lighting output will vary inversely
with daylight availability.Over illumination should be minimised
to reduce excessive energy loss,therefore,placing
considerable importance on lamp choice and installation
layout.
Mounting of daylight sensors for the control system should be
such that they are installed in locations representative of the
task area and the set-points should reference the daylight
incidental on the working plane.
13. 4-GUIDELINES TO SPORTS LIGHTING
Increased leisure time,along with advancements in illuminating
engineering design and technology,have brought about an
increase in sporting events played and watched at night.Light
source efficacies have more than doubled;drastically reducing the
energy requirements of sports facilities in spite of increased illumi-
nances to satisfy the elevated skill level of modern athletes.
Associated with the improved illuminance levels are increased
problems of glare and color rendering for better visual performance
and quality television broadcasting.Sports lighting has outgrown
the design by approximation,it requires sophisticated computer
programs for application.This requires a thor-ough understanding
of illuminating engineering principles and associated computer
programs by the lighting designer.
Class of Play
As the skill level of play is elevated,players and spectators require
a more criti-cally illuminated environment.There is a correlation
between the size of a facility and the skill level of play,i.e.,the
number of spectators is directly related to the skill level of play.To
determine illumination criteria,facilities are grouped into
fourclasses to satisfy the skill levels.
Class I -for competition play before a large group of spectators.
Due to the complexity of design for major stadiums requiring
special design consideration, the criteria presented for this class
will be for spectator capacity of 10,000 or less.
Class II -for competition play with approximate spectator capacity
of 4,000 to 6,000.
Class III -for competition play without specific provisions for
spectators.
for social and recreational play only.-Class IV
14.
15. Natural light in swimming pools
is an increasingly attractive option for indoor aquatic facilkites.large windows
or open fenestration can be energy-efficient ways to supplement artificial heat
and lighting.
However, natural light can be accompained by an undesirable partner
_glare.glare rom poorly positioned window openings can turn competitive
swimmers into unidentifiable anonymous silhouettes in front of
coaches,spectors and television cameras.
Reflections occur when light rays hit a surface and bounce off.the angle at
which the ray hits the surface is equal to the angle at which it bounces off. We
perceive the glare beacause of the highly reflective nature of water and the
sharp contrast between the light from the windows or artificial light source and
the relative darkness of the surrounding walls,celling and floor .
The worst-case glare problem occur when viewers spectators,lifeguards_are
positioned oppisite windows.wall openings or artificial lighting with the pool in
between.
Contrasting elements of light and dark can shed unwanted reflections on
water’s surface any time the light source is within the field of vision of the
viewer.
Solving glare problems is frequantly simple .if light can be provided without
the river experiencing light and dark contrasts in his or her field of vision, the
most objectionable glare will be eliminated.the most commen architectural
solution in constucting new competitive venus is to place the windows or other
fenestration behind the spectator sands so light washes over the ceiling to the
far wall and down to the pool dack.as shown in the figure below:
by positioning the light source dehind the viewers,out of their line of
vission,intense of reflections and glare problems are avodid.
Windows and open fenestration on oppisite walls can be controlled by
cosucting opaque wall,partitions(as in the figure below):
16. or facades,soffits or baffles(as in the figure below)to block the direct
light,allowing indirect,deflected light to bounce off the structure and spell into
the nataorium space.
In designing these features,careful considration should be given to wall
coloring,using combinations of light and dark surfaces areas to maximize the
effectiveness ot the indirect natural light.
Glare caused by end-wall lighting is not as serve as that created by oppisite-
wall lighting,but it can be a problem,particularly for compotitive swimmers
performing the breaststoke,backstroke or butterfly.
An attractive solution to end-wall lighting problems is a wall design using saw-
tooth panels to direct light away from the water.(as shown in the figure below):
17. Sky light are usually not problematic, since the angle of reflection from an
over head source is normally not great enough to be an issue (as in the figure
below):
If glare compromises the view from high spectator seating, however, a
recessed clerstory can be installed to achieve top-lighting with the same
indirect benefits as achieved with baffles(asshown in the figure below):
18. the preferred positioning, then,for overhead lighting in a competitive pool
enviroment is directly above the water surface.this is particulary important for
pools wihout underwater lighting.
Casting light straight down penetrates the deep water most efficiently and
creates aminimum of shadows.at greater angles, more of light is reflected off
the water surfae, casting bigger shadows from the pool edge and causing the
bottom of the pool to appear darker.
The relation between the pool and the building surrounding it and we take in
care not to construct buildings which could make shadows so as not to affect
the vision of the attendance and the players.
The relationship between the sun and the jumping pannel (اﻟﻘﻔز .)ﻣﻧﺻﺔ
19. 1- Oita Main Stadium:
location: Kyoto,Tokyo
Usage of natural light: Skylight and Materials.
• To give the field adequate
sunlight exposure, the
elliptical roof opening runs
along the north-south axis.
• The stationary portion of the
roof is clad in titanium, giving
it a futuristic appearance. The
noticeable interior lightness is
thanks to the Teflon panels of
the movable roof structure.
• The use of ultra-modern Teflon
membrane panels with 25%
light-permeability removes the
need for artificial lighting
during daylight hours.
