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MEASURES AND EQUIPMENT OF A STANDARD POULTRY HOUSE

The environmental simulation is calculated considering a poultry house with the following features:
- 120 meters long by 17 meters wide
- 2.2 meter high wall and ceiling 4.2 meters maximum height
- Cross ventilation (winter) and tunnel ventilation (in summer)
- 37 Radiant brooders
- 78 square meters of cooling pad system.
- Ceiling insulating material: 4 centimeters thick of polyurethane foam board faced on both sides with aluminum foil
- Wall insulating material: 5 centimeters thick of polyurethane sandwich panel
- Cost kilowatt/h.= 0,11 €
- Cost of propane 0,93 €/Kg.

If you want to make environmental simulation on a poultry house different from 'Standard House', you must first go into 'CALCULATION OF EQUIPMENT'.

SIMULATOR

INPUTS COLUMN

ENVIRONMENTAL AND PRODUCTION DATA

Outdoor temperature

ºC

Outdoor Relative Humidity

Desired Indoor temperature

ºC

Please observe the birds and acording to their behavior, reset the theoretical data of the temperature tables.

DESIRED R. Humidity int.

IN WINTER:
It is recommended the level of inside humidity of 65% all the time.
It is not recommended for the litter to have a continuous inside humidity of 75%.

Number of birds

birds

Average weight per bird

39 kg/m² is the maximum population density allowed by European legislation (under normal conditions).

HEATING SETTING

State of heating

Heating offset

ºC

The number of degrees in the poultry house below the desired temperature so that the heating system is switched (only if connected)

RECOMMENDED:
From -0.5 º C in young birds to - 4 º C in adult birds

SLIDER TEMPORARILY DISABLED

Resultant internal temperature to start heating

PROGRAMMING OF THE STATIC PRESSURE

Current static pressure in the poultry house

pascals

IN CROSS AND LONGITUDINAL VENTILATION:
Static pressure recommended depending on the width of the House according to 'COBB Broiler Management Guide (revised 2010)'
IN TUNNEL VENTILATION:
Advised static pressure taking into account the pressure drop due to air friction, calculated with the Darcy-Weisbach equation (which at the same time depends on the section of the house and the air velocity).

MINIMUM VENTILATION SETTING

Minimum ventilation flow

m³/h

Maximum level of CO2 allowed

PROGRAMMING THE START OF VENTILATION DUE TO EXCESS TEMPERATURE

Degreess above desired temperature

ºC

Temperature that the poultry house has to reach, above the desired temperature, so that it leaves the minimun ventilation and begins ventilating due to excess temperature.

RECOMMENDED:
From 2 ºC in young birds to 0.5 ºC in adult birds

Inside resultant Tª to start ventilation by excess Tª

Offset of each no tunnel fan

ºC

When we ventilate due to excess temperature, the temperature that there should be in the poultry house (above 'resultant temperatura to start ventilation by excess temperatura') so that one new 'not tunnel' fan begins to operate (in addition to the minimum ventilation).

RECOMMENDED VALUE:
You can vary this value so that the 'sum of offsets of all no tunnel fan' is 3,5 ºC .

Sum of offsets of all no tunnel fans

When we ventilate by the ventilation tunnel, the temperature that there should be in the poultry house (above 'resultant temperatura to start ventilation by excess temperatura'), so that all 'no tunnel fans' are working
RECOMMENDED VALUE: 3,5 ºC

TUNNEL VENTILATION PROGRAMMING

Degrees above the desired temperature to start tunnel

ºC

Temperature difference there must be between the outside of the farm and the 'desired indoor temperatura' to start tunnel ventilation.
You can vary this value so that the 'outdoor resulting temperatura to start tunnel ventilation ' can be between 28 º C and 35 º C depending on the age of the birds.

Resultant OUTDOOR temperature to start Tunnel

Offset of each tunnel fan

ºC

When we ventilate by the ventilation tunnel, the temperature that there should be in the poultry house (above the onset temperature of tunnel ventilation), so that a new tunnel fan begins to operate.

RECOMMENDED VALUE:
You can vary this value so that the 'sum of offsets of all tunnel fan', is:
from 8 ºC in young birds to 3 ºC in adult birds.

Sum of offsets of all tunnel fans

COOLING SYSTEM PROGRAMMING

Degrees above the desired temperature to start cooling

ºC

Temperature difference there should be between the outside of the farm and the desired indoor temperature to start cooling.
You can vary this value so that the 'outdoor resulting temperatura to start refrigeration' can be between 28 º C and 35 º C, depending on the age of the birds and tunnel ventilation if available.
Not recommended to start cooling:
-Inside temperature under 28 º C.
-Birds younger than 28 days old.

Resultant OUTDOOR temperature to start cooling

% maximum moisture with cooling

It is recommended switch off the cooling when the percentage of moisture in the poultry house is above 75%

Air flow in cross ventilation with humidifying working

m3/h.kg

caution
PARAMETER VALID ONLY IN CROSS VENTILATION houses.
Recommended 4 m3/kg.
We can even vent with 3 m� / kg meat (getting more cooling), but only if there isn�t less than 15% outside relative humidity.

RESULTS COLUMN

AVERAGE ENVIRONMENTAL VALUES INSIDE THE POULTRY HOUSE

Average temperature inside the poultry house
Average humidity content in poultry house
CO2 concentration in House (in P.P.M.)
Average air velocity at the height of the birds (in meters / second)
Thermal PERCEIVED SENSATION by birds taking into account the temperature, humidity, air velocity and age of birds (approximate value).

CURRENT VENTILATION TYPE

CURRENT VENTILATION TYPE:
VENTILATION MODES

FLOW VENTILATION

Minimum ventilation flow
Ventilation flow excess temperature
VENT FLOW TOTAL (REAL)		Resulting ventilation coefficient

NUMBER OF FANS RUNNING (considering current static pressure):

AIR INLET IN THE FARM

Caudal de aire que entra por las trampillas
% opening of side wall air inlets

Air velocity at the entrance of the house
Atmospheric static pressure inside the poultry house

INTAKES

Feed	Daily feed intake
Water	Drinking water intake by birds
	water intake to environmental humidification

Propane consumption:		Propane Cost (in €):
Electricity	Instantaneous electricity consumption of the ventilation
	Electric Cost of the ventilation

PRODUCTIVE PARAMETER COMPARISON between the current temperature
and the more profitable temperature

NOTICE
Temperature with the lowest
conversion: 21.8ºC.
Higher growth temperature: 18ºC.

Source: Yahav et al. (1996).

CALCULATIONS ZONE

COEFFICIENTS

Side air inlet velocity according to the width
m² Side air inlet installed
tunnel air inlet velocity				m/s
m² air inlet installed in ventilation tunnel
Actual small fan flow		m³/h
Actual big fan flow		m³/h
Number of tunnel fans used in transitional
Number of tunnel fans used in tunnel level 1				m³/h
Total Heat bird (Qs + Ql) 20ºC		W/bird
Adaptation Qtotal (different Tª) at 1000w		W/1000 W
Adaptation Qsensible (different Tª) at 1000w		W/1000 W
Qtotal (Ql + Qs) / bird (inside Tª)		W/bird
Qsensible / bird (by formula)		W/bird
Qlatente / bird (by formula)		W/bird
Actual moisture emission per bird		g water/bird/hour
Qlatente / bird (Real)		W/bird
Absolute humidity outside		g/m³		kg water /Kg air
Wet bulb temp outside air			ºC
Eficiencia sistema de humidificación		%
Outside air enthalpy		kj/kg
Atmospheric pressure		milibares
Humidity abs. desired interior (c. real)		g/m³		kg water /Kg air
REAL abs humidity inside mean		g/m³		kg water /Kg air
abs humidity inside start house		g/m³		kg water /Kg air
abs humidity inside half house		g/m³		kg water /Kg air
Humidity inside abs end house		g/m³		kg water /Kg air
INSIDE air density considering the temp, Hª and atmospheric Pressure		Kg/m³		km³/kg.
	Z=
	Xv=
OUTSIDE air density considering the temp, Hª and atmospheric Pressure		Kg/m³
	Z=
	Xv=
Specific heat of air		j/kgºC
Latent heat of vaporization at 20ºC			j/kg
Value number e
Calorific power propane			j/kg
Water consumption bird / day (formula)			mililitros
(*) Feed consumption per bird at the temperature where you get the best performance (21.8 ºC)				gr/day
				gr/day
(*) Growth per bird at the temperature where you get the best performance (21.8 ºC)				gr/day
				gr/day

(*) valid birds between 5 and 8 weeks of age

CALCULATION OF MINIMUM VENTILATION REQUIREMENTS (for O2, CO2 and humidity)

Ventilation needs to provide OXYGEN	consumed by birds	m³/h
	consumed by heating	m³/h
	Total requirements for O2		m³/h/kg liveweight
Ventilation needs to remove CO2	produced by birds	m³/h
	produced by heating	m³/h
	Total requirements CO2		m³/h/kg liveweight
Ventilation needs to remove moisture	produced by the birds	m³/h
	produced by heating	m³/h
	Total requirements water		m³/h/Kg. liveweight
Total NEEDS OF MINIMUM VENTILATION			m³/h/Kg. liveweight
Minimum ventilation flow advised by Ross			m³/h/Kg. liveweight

CALCULATION OF VENTILATION NEEDS TO REMOVE THE EXCESS TEMPERATURE

Ventilation needs to remove the excess temperature of the poultry house

m³/h/Kg. liveweight

ENERGY BALANCE STUDY OF THE POULTRY HOUSE

Metabolic heat brought by birds
Heat transmitted by enclosures	Heat transfer from the wall
	Heat transfer from the roof
	Total heat
Heat lost by minimum ventilation
Semibalance
Heat from the heating
Heat lost by ventilation of excess temp without humidification
Heat rejected by refrigeration

Ending Balance		close to 0 W

The house is in thermal equilibrium, so that the indoor temperature is stable over time