Method for Calculation Parameters Natural Ventilation System of Animal House

Abstract

Ventilation is a key element in the successful operation of any animal production facility. In designing a natural ventilation system for animal house it is necessary to assess the ventilation induced by thermal buoyancy and wind forces. The ratio of thermal buoyancy and wind was established and the methodology was prepared to forecast ventilation intensity based on the calculations of air speed in inlet and outlet openings. The equation was formed to calculate the ratio of size inlet and outlet areas. The accuracy of the methodology was approved by experimental research under natural conditions of barn operation. The difference between the experimental and calculated air speed values in the outlet opening was insignificant and was within 0-8 % range. According to the analytical and experimental research results it was calculated that in a typical animal house air speed in the aperture of the rooftop there is 1.3 rn/s (when there is no wind, this speed decreases to 0.3 m/s), ratio ventilation rate of thermal buoyancy and wind forces - 0.27; and in order to have all air removed through the rooftop aperture in winter, the area of inlets in the walls does not have to exceed 40 % of the rooftop aperture area.