artificial ventilation of poultry house the importance, divisions , tunnel ventilation , practical application

1. ventilation
Artificial Ventilation

2. Poultry house ventilation is important
because:
1- we need fresh air to fill the needs due to higher MR & stocking
densities.
2- birds need good environment.
3- we want to expel excessive heat , harmful gases “
NH2,Co2,H2s”.
4- we need dry litter to avoid disease.
5- it helps in reducing temperature , humidity and air
contamination to tolerable limits for confined chicks.

4. Ventilation system
• Generally divided into two groups:-
1- natural ventilation. Windows
2- artificial “ mechanical” ventilation. Fans
Mechanical air movement is required to ventilate the
house in all climate conditions, And this system is the
suitable one for climate change.
We use electric fans as principle components to
exchange air in the building.

5. • Mechanical system subdivided into 2
distinct types [ Positive & Negative
pressure].
- Positive Pressure:
• Fans arranged to push fresh air into the building.
• Creates air velocity which produces wind chill effect.
• For rearing at higher stocking densities in extreme
climatic conditions.
This system is not very effective.

6. - Negative Pressure:
• Fans arranged to expel the air from the building.
• They create a partial vacuum or –ve pressure in
side the house. “ the pressure difference pulls fresh
air into the house through inlets.
• The location , distribution , size of fans and inlets
are critical if all areas of the house are to be
ventilated.
We may term this system best fit for our climatic
conditions.

7. “positive pressure” “Negative pressure”

8. Operation in different
condition
 Cold weather ventilation {Minimum Ventilation}.
 Hot weather ventilation {Tunnel Ventilation}.
 optimum weather ventilation {Transitional ventilation}.

9. • Minimum ventilation
-Is used to provide fresh air inside the house during cold weather
it removes excessive moisture and minimize heat loss.
-The air inlets are installed either in the ceiling or high on the
house side wall , these inlets are designed to direct air across the
ceiling allowing it to mix with warmer air located there and to heat
up before coming in contact with birds.
-Check the temperature and determine the heating necessity,
doing this will help in minimize heating costs.
-For large scale commercial production , you can install
automatic computer controllers.

10. • Tunnel ventilation
-For keeping the birds cool during hot weather we use tunnel
ventilation.
-This system removes excessive heat very fast and make a wind
chill that provides the birds additional cooling.
-Evaporative cooling system is also used for cooling the house
when tunnel system is not sufficient enough.
-Tunnel system in broiler house consists of large air inlets at one
end and fans in the opposite end , the fans used in one end is to
pull air the length of the house at velocity 5ooft /min or more.

11. Tools of tunnel
ventilation
 Exhaust fans
 Cooling pads
 Tunnel door

12. 1- Exhaust fans :
Expel air out of the building and
combination produces
velocity of air in the house.
Number of fans determined by :
cross section × desired velocity
CMF of one fan

13. 2- Cooling pads:
It is a pad made up of cellulose
with different flute angles.
When we pour water upon pads
and air passes through wet flutes
the air cools down due to addition
humidity.
Then cooled air pulled in single
direction by the exhausted fans
through out the house.

14. 3- tunnel door
4- cooling pad motor
5- controller
6- temperature sensors
7- humidity sensors
8- humidity switch
9- power track for the operation
of tunnel door

15. Tools working sequence:
Tunnel fans : on
Min. ventilation fans : off
Cooling pad : open
Vents : closed
Evaporative , cooling : on
Tunnel door : open

16. • Points to be considered in tunnel
ventilation
 ventilate the tunnel when only cooling the bird is the goal.
 Turn on the right number of fans depending on the age of the
bird.
 Do not run fewer than the half of fans if you intended to be
tunnel ventilating.
 Monitor and maintain adequate the air flow.
 If running operative pad cooling static pressure should be 0,05
to 0,1 inches of water column.
 Watch the bird not only thermometer to see how much cooling
is needed.

17. Ventilation during hot and dry weather
• With increasing in temperature and age of birds we may keep
on operating more fans until we reach to a velocity of 1 minute
air change.
• If the effective temperature felt by the bird is still high then we
have to operate cooling pads.
• When the air passes through the wet cooling it is cooled down
in dry weather and directed towards the ceiling to avoid chilling
of the bird at pads area.
• The cooled air would be transported to the end of the house in
1 min, so temp of the house must come down quickly and
sensed by the sensors and conveys to controllers, then it
brings down velocity by shutting off fans to avoid chilling by
combined effect of low temp and wind chill.

18. the table shows the parameter and the recommended levels
The general comfort zone for bird is between 20 and 30°C
however, day old chicks can`t maintain their body temp if the
temp is below 26°C.
Therefore, the recommended barn temp for the first week is 30
to 32°C , after that temp may be lowered by 2 or 3 degrees
every week until the 6 one, then can be maintained between 10
and 27ºC.

19. The practical application of the
field

20. The view from out side the
house “ exhaust fans”

22. Out side view of the house

23. The Heater

27. Cooling pads

28. controllers

30. Thank you
for your attention
