What size water curtain does your chicken coop require? And what are the wind speed requirements?

01 Model of cooling pad

The models of cooling Pad are generally divided into two categories, based on the different angles between the water inlet angle and the air inlet angle, namely 7060 and 7090 specifications;

02 Wind speed through the curtain

The selection of cooling pad needs to consider meeting two conditions:
(1) The negative pressure increased by the cooling pad is within a controllable range, generally not exceeding 20Pa;
(2) The cooling efficiency of the cooling pad reaches over 75%.
To meet these two requirements simultaneously, the maximum air velocity through cooling pad of different models and thicknesses varies. Taking the commonly used 7090 and 7060 models of 150mm thick cooling pad in chicken houses as examples, let's see how to determine the maximum air velocity through the wet curtain.

As shown in the figure, the air velocity passing through the curtain corresponding to a pressure loss of 20Pa is 1.2m/s for a 150mm thick 7090 cooling pad and 1.8m/s for a 150mm thick 7060 cooling pad. Additionally, the air velocity passing through the curtain corresponding to a cooling efficiency of 75% is 4m/s for a 150mm thick 7090 cooling pad and 1.8m/s for a 150mm thick 7060 cooling pad.
In summary, the air speed passing through a 150mm-thick 7090 cooling pad should not exceed 1.2m/s, and the air speed passing through a 150mm-thick 7060 cooling pad should not exceed 1.8m/s

03 Area of cooling pad

The area of the cooling pad in the chicken coop is determined by the maximum ventilation volume of the coop. When calculating the area of the cooling pad, it is necessary to refer to the design wind speed across the curtain. For example, if the maximum ventilation volume in summer is 800,000 m³/h, then the area of the cooling pad = maximum ventilation volume in summer ÷ wind speed across the curtain
=800000m³/h÷1.8m/s÷3600s/h=123.45m²
Does it mean that the larger the cooling pad area and the lower the wind speed passing through the cooling pad, the better the cooling effect in the chicken coop? The answer is no.
As the area of the cooling pad increases, the cooling efficiency will correspondingly improve, and the resistance to ventilation will also decrease. However, the improvement in cooling effect of the wet curtain is limited. Moreover, in tunnel-type ventilated chicken houses, the low wind speed through the wet curtain can lead to increased ventilation dead zones at the cooling pad location, and the investment will also increase.