Measuring Ventilation Rates in Livestock Buildings with an Averaging Pitot Tube

An averaging Pitot tube (measures the cross sectional flow in a duct) was designed and constructed to measure ventilation rates from a animal confinement facilities. The low cost averaging Pitot tube was developed using Air Movement and Control Association (AMCA) standards. The Pitot tube was calibrated against a 0.41 m orifice plate using a fan test apparatus. The Pitot tube readings correlated closely with those from the orifice plate, therefore confirming the accuracy of the averaging Pitot tube. A 1 Mbar-D-4V sensor was used to measure the pressure (volts) from the Pitot tube and was calibrated to the calculated airflow (L/s) from the orifice plate. The resulting equation can be used to determine the present airflow in ventilation ducts downstream from exhaust fans.