Common phenomena and improvement measures of improper use of fan and wet curtain in summer

In the summer, many of our farmers are worried about the problem of ventilation. Either they can't lower the temperature and they get heat stress heat stroke, or they don't have a good grasp. In fact, these problems are mainly caused by too low or too high wind speed, wrong wind direction, and excessive humidity. The reasons for these are not only the configuration of the fan wet curtain, but also the reasons for improper operation. Let me analyze the common phenomena in the concentration and talk about the improvement measures.

Why are some chicken houses 28 ° C chickens all right? Why are there chicken houses with 28 ° C chickens with open mouths?

The crux of the problem: the chicken back wind speed is too low, and the chicken feels the temperature is high. When the house 28 ℃, assuming the house relative humidity is {{{{{5}}}}%, and the wind speed is 2 m / s, the chicken ’s somatosensory temperature is 2 2 ~ 2 3 ℃; when the wind speed is {{5}}. 5 m / s, the chicken ’s somatosensory temperature is {{2 }} 4 ~ 2 5 ℃; the wind speed is {{5}} m / s, the somatosensory temperature of the chicken is 2 5. {{ 6}} ~ 2 6 ℃.

Reasons 1: Some farms only consider the general high temperature in summer and ignore the high temperature and high humidity climate, in order to save investment. Less fan configuration. In high temperature and high humidity weather, the cooling efficiency of the wet curtain is low, and the somatosensory temperature of the chicken can only be reduced by enhancing ventilation.

Reason 2: The quality of the fan wet curtain is poor, the performance is unstable, and the exhaust efficiency is low under a high negative pressure state. For example, for some fans, the 0pa static pressure exhaust capacity marked on the nameplate is 43000 m {{3}} / h. However, due to the shape and material of the fan blade, the strength is not enough. {0}} The exhaust capacity of 0pa under negative pressure operation is only {{3}} 0000m {{3}} / h, which is far lower than the general {{3}} 7000m Data for {{3}} / h.

Reasons 3: The fan lacks maintenance, the bearing wears, the triangle conveyor belt is loose, or is blocked by chicken feathers. If it is not replaced and cleaned in time, the exhaust efficiency of the fan decreases. Or the fan is aging and will not be replaced in time.

Reason 4: calculation error, too few fan configurations. I have seen a large modern broiler farm with cascading cages and chicken house specifications {{1}} m * {{2} m * 4. {{4 }} m ~ 6 m, vertical tunnel fans 2 4, walkway wind speed 3. 1 m / s, inside the cage 50 The wind speed in the depth of cm is only 0. 75 m / s, and the feeding effect in summer is not very good. If the chicken farm is built in a dry climate region in the northwest, the wet curtain can reduce the temperature in the house to 2 3 ~ 2 4 ℃. no problem. However, in fact, the chicken farm is built in the coastal area. The average humidity in summer is 80%, and the efficiency of cooling and cooling of the wet curtain is low, mainly relying on fan ventilation to cool down, and the fan configuration is small.

Improvement method: maintenance, even if replacing bearings and V-belts, clean chicken feathers; replace the fan with a long service life and low exhaust efficiency; if the configuration is too small, increase the fan wet curtain configuration, the configuration calculation should be in harsh high temperature and high humidity Based on the required wind speed.