Evaporative Cooling System for broiler

sir,Munawar sb , the actual problem is the high humidity . put ur pads on timers and again it is suggested to increase the speed of air in the shed either by increasing the no of fans or placing wind barriers(baffles ) . a combination of fans&baffles will also work. thnk u sir munawar ,

I work with pad cooling in all summers. Indeed , when the humidity is hight , only tunnel ventilation can help you. But offcourse , without starting pads.From my experiences , in this condition , you must have 4m/sec ( we have 4.4.m/s).When humidity is hight , you must modify the external presure in order to help birds to loose humidty If you want , give me all information about your houses (width, height) and nr and capacity of the fan. I will try to make a simulation.I need size and nr of tunnel inlets.

In hot and humid weather cooling through evaporation is decreased. Combination of evaporative cooloing and wind chill effect by increasing the wind speed can help to solve the problem. Followings should be checked. 1: - In hot and humid weather due to high temperature almost all fans installed are operative which increase the static presure in house. Increase in static presurre reduces the air displacement capacity of fans installed. Fan capacity calculated on zero static presurre will reduce the Fan capacity at higher static pressure is reduced. 2: - Flute angle and flute size of the cooling pad has effect upon airflow through cooling pads. In our areas mostly 45/45 flute angle pads are installed which have more resistance to air in comparison to 45/15. It is suggested please have right type of flute angle asper requirement to manage in house humidity. 3: - In summer if volatage and cycles of electricity are below standard requirement, then RPM of fans is reduced which result in reduction in air displacement. It is suggested stabilizer (Electricity) should be installed to have optimum air speed for better wind chill effect. 4: - Cleaning and maintance of fans (blades particularly), cooling pads (Water distribution system and clogging clearance) should be done periodically on regular basis, so that fans function in full capacity and pads remain clean for lesser air resistance passing through. clean pads and water distribution system over pads will help in complete wetting of pads for proper evaporation. 5: - Timers should be installed on water pumps for pads to regulate the on and off time of watering/ pumping for reduction of humidity in house. It is ideal when the evaporative pad becomes wet, further showering of water on pads should be stopped. When the pad is near to dry (not dry) again showering of water will start in same way. It will give more cooling effect along with reduction in humidity. Time adjustement for pumpd on and off time will be adjusted on the basis of observation of drying and wetting time of cooling pads (which is variable depending upon environmental (exrenal) temperature and relative humidity). 6: - When the outside humidity is higher (more than 75%), then by increasing the air speed through wind chill effect is only helpfull. For this one may need installation of more fans. Recirculating fans installation in the dead pockets within shed where there is lesser air speed can help in control of high temperature. 7: - It should be emphasized that balnced safe feed is given to birds for dry dropping. It will help in reduction in addition of moisture through evaporation of loose droppings water. Gut health will avoid watery dropping which will indirectly help in in house environment particularly moisture. In hot and humid weather it is difficult to achieve the ideal humidity & temparture in house, but by combined effects of factors mentioned above will help in decreasing the severity of hot weather. Dr. Maqsood Jaffery

Based on my exprience in different parts of the Middle East, tunnel cooling system found less effective than to use cooling pads in the middle of the poultry house and fans on both sides of the house.Number of fans should be double than tunnel cooling e.g. if 8 fans were used in tunnel cooling than 16 fans should be use in suggested system i.e. 8+8 on each side. This is the best practical solution of controlling high humidity inside the poultry houses. Dr. Mohammad Akram, Consultant Microbiologist, Micro Laboratories Karachi Pakistan.

another option , i practiced is , place 2-3 fans in the middle of the shed, these fans will bring cool air fastly towards the exhaust fans . the fans side of the shed has higher temperature than the pads area. in the early stage of placing fans in the middle will temporarily disturb the birds but in the later stages they will become habitual. some arrangements like feeder /drinker placement change infront of fans will b required. these fans should b installed alongwith the flock placement so that birds do,nt get frightened. these fans will only work during high temperature and high humidity.

Aoa when outside Rh exceeded from 50 % with 38 C out side temp,it become very difficult to remove the moisture from the inside of the house.As bird is continuously omitting moisture inside of the house in the form of his own oral evaporation and in feaces. In such type of situations with doing all the good things as explaind in above all coments we could maintain the temperature at 29.5 C with RH% 85% inside the house .I am totally convinced that RH% inside the House become impossible to control in hot and humid weather with evaporative cooling System. With This System we can only do the practices which have been already Discussed in above coments by Stanley , Dr Jaydip , Syed mehmood akhter , rao Zulqarnain and all other comments Dr Manwar, Please mention the outside Temperature and Relative Humidity as well as inside ,house Dimensions , total air exhaust capacity in terms CFM ,And density of birds , . I think 34C temperature may be reduced upto round about 30 C DR ASHFAQ AHMAD

aoa

Respected Dr. Munawar Ali, May be this hypothese help you in this regard. It is difficult to keep bird cool with air speed only Digesting and metabolizing feed produces a considerable amount of heat. For instance, a five-pound-broiler produces roughly the same amount of heat as a 20 watt light bulb. Understanding how temperature, humidity, and wind speed affect a bird’s ability to rid itself of excess heat is essential when trying to determine how best to manage a tunnel ventilation system during hot weather. A bird rids itself of excess heat in primarily two ways: it gives off heat to the air around it (sensible heat loss) and it loses heat through the evaporation of water off of its respiratory system (latent heat loss). Sensible heat loss is fairly simple to understand. The bird’s body is warmer than the air and therefore the bird loses heat to the air surrounding it. The cooler the air, the greater the amount of heat loss. The warmer the air, the lower the amount of heat loss. Latent, or evaporative heat loss, can be a harder concept to understand. As a bird breathes, moisture evaporates from the respiratory system. As this moisture evaporates, heat is removed from the bird just like the evaporative cooling pads “remove” heat from air entering a house during hot weather. As you might expect, the amount of heat a bird loses through the evaporation of moisture off of its respiratory system depends on the relative humidity of the air it breathes. The lower the relative humidity, the more moisture the bird can evaporate off of its respiratory system and the more heat that can be removed from the body. Conversely, the higher the humidity, the lower the amount of moisture evaporated from its respiratory system and the lower the amount of heat removed. The total amount of heat being removed from a house during hot weather can be determined if one knows the temperature and relative humidity of the air entering and leaving a house, and the air exchange rate. Measuring temperature and relative humidity is fairly simple but determining air exchange rates accurately can be difficult. Another complicating factor is that we are not as interested in the total heat removed from the house as much as we are the portion removed from the birds. In August of 2010, a short study was conducted in a 150,000 bird commercial layer house to examine how air temperature affects the heat loss from birds in a tunnel house during hot weather. The study was conducted in this specific type of house for a number of reasons. First, it was a very basic tunnel house. All the fans were in one end wall, and all the tunnel openings were in the opposite end wall. This made the house air exchange rate extremely uniform from wall to wall and from floor to ceiling. Secondly, the house had no evaporative cooling system. This was important because without an evaporative cooling system, the heat loss from the birds at high ambient air temperatures could be determined which would have not been possible had evaporative cooling pads been in use. Last but not least, this type of commercial layer house has a very high density of birds per cubic foot of house volume compared to a typical broiler house. This meant the heat gained through the walls and ceilings was insignificant (less than 1%) relative to that produced by the birds. ..

Thank you mr Munir for your very profesional comments.Indeed this are the two way to lose heat from birds.And if the sensible heat loss is not enough you must latent heat loss.And for this , you must increase the hydrostatic presure .

you must use the latent.... sorry

Yes it is difficult to keep birds cool with air speed alone. Digesting and metabolizing feed produces a considerable amount of heat. For instance, a five-pound-broiler produces roughly the same amount of heat as a 20 watt light bulb. Understanding how temperature, humidity, and wind speed affect a bird’s ability to rid itself of excess heat is essential when trying to determine how best to manage a tunnel ventilation system during hot weather. A bird rids itself of excess heat in primarily two ways: it gives off heat to the air around it (sensible heat loss) and it loses heat through the evaporation of water off of its respiratory system (latent heat loss). Sensible heat loss is fairly simple to understand. The bird’s body is warmer than the air and therefore the bird loses heat to the air surrounding it. The cooler the air, the greater the amount of heat loss. The warmer the air, the lower the amount of heat loss. Latent, or evaporative heat loss, can be a harder concept to understand. As a bird breathes, moisture evaporates from the respiratory system. As this moisture evaporates, heat is removed from the bird just like the evaporative cooling pads “remove” heat from air entering a house during hot weather. As you might expect, the amount of heat a bird loses through the evaporation of moisture off of its respiratory system depends on the relative humidity of the air it breathes. The lower the relative humidity, the more moisture the bird can evaporate off of its respiratory system and the more heat that can be removed from the body. Conversely, the higher the humidity, the lower the amount of moisture evaporated from its respiratory system and the lower the amount of heat removed. The total amount of heat being removed from a house during hot weather can be determined if one knows the temperature and relative humidity of the air entering and leaving a house, and the air exchange rate. Measuring temperature and relative humidity is fairly simple but determining air exchange rates accurately can be difficult. Another complicating factor is that we are not as interested in the total heat removed from the house as much as we are the portion removed from the birds. In August of 2010, a short study was conducted in a 150,000 bird commercial layer house to examine how air temperature affects the heat loss from birds in a tunnel house during hot weather. The study was conducted in this specific type of house for a number of reasons. First, it was a very basic tunnel house. All the fans were in one end wall, and all the tunnel openings were in the opposite end wall. This made the house air exchange rate extremely uniform from wall to wall and from floor to ceiling. Secondly, the house had no evaporative cooling system. This was important because without an evaporative cooling system, the heat loss from the birds at high ambient air temperatures could be determined which would have not been possible had evaporative cooling pads been in use. Last but not least, this type of commercial layer house has a very high density of birds per cubic foot of house volume compared to a typical broiler house. This meant the heat gained through the walls and ceilings was insignificant (less than 1%) relative to that produced by the birds. .

incraes the air spead isthe only solution during hot and humid weather

Sir, If you instal the fans in your houses on basis of bird weight then your birds are very comfertable even in high humidity e g 5 CFM / Kg body weight.

Is interresant to receve some data about houses (section, inlets number and size, height, long e,t,c, , number of birds , weight of hatch e.t.c.) and make some models for ventilations.Is verry important humidity and termperature of day and night of this zone.In my contry (Roumania) the could of winter is a limitative factor for broiler business.Is interesting if too much heat can be limitative or not in broiler bussiness.

I read the detailed opinions of all the expert and what feel that DR SYED AKHTAR AND DR JAYDIP MULIK suggestions are valid and the answer lies in their suggestions.,still with high humidity and temperature it is a big circus on breeder farms

Please , mr. Nitin , inform me what humidity is inside and outside of the houses?

ask the questions to the Mechatronics Engineering people . mechanics , machines and the automation are their jobs. only tell them what the birds needs. regards