Method for estimating and analyzing an increase of efficiency of the ventilation system in a livestock house

Аннотация

A method of comparative evaluation of a centralized ventilation system using and not using an ejection unit is developed. The aerodynamics fundamentals are used to substantiate the efficiency of the ventilation with the use of the ejection unit as well as to substantiate its parameters. It is specified that the main parameter of the ejection unit is the ejection coefficient defining the rate of an increase of the air supply due to ejection or the same amount of the ejected air. The structural parameters of the unit, its components, depend on this parameter: nozzle, pressure, mixing chambers, and supply shaft. The analysis of the standard designs of the livestock houses shows that the total resistance of the network of the supply ventilation system makes 600–800 Pa. That is why the ejection coefficient of the units can be assumed to be equal to three. Furthermore, the energy costs are reduced 2.4 times. It is specified that the best conditions for admixing the warm air are created at the smallest angle between the ejecting and ejected air, i.e., with the following motion of the flows.