Criteria for Ceiling Slot-Ventilated Agricultural Enclosures: Non-Isothermal
Experiments using two scale–models were conducted to study non–isothermal airflow similarity in a ceiling slot–ventilated agricultural enclosure. The main criteria used for determining similarity were airflow pattern similarity, occupied zone airspeed, and temperature similarity. For agricultural ventilation issues, these were projected to be paramount to a successful scale–model study. The current study, based on past agricultural ventilation studies, focused attention on the Archimedes number (Ar) and Momentum ratio (Rm) as the similitude criteria for non–isothermal airflow. Results indicated that Ar is the appropriate similitude criteria for non–isothermal airflow patterns under strong buoyancy–affected conditions where Ar > 0.015. With increasing airflow or decreasing temperature differences, resulting in a lower buoyancy–affected air–jet, Rm with a consistent overall temperature differential was determined to be the appropriate similitude criteria. This study focused on practical considerations for conducting scale mode studies such as scale–model conditions measured in the animal occupied zone and it’s relation to expected prototype behavior.
This article is from Transactions of the ASABE 45, no. 1 (2002): 201–214.