Modelling of air distribution methods for zoning strategy.

Zonal models are often used in analytical calculation of temperature, concentration or humidity conditions in ventilated spaces. The space is divided in two or several zones ( 1 ). The zoning of the space is based on the assumption of constant temperature,  concentration and humidity in each separate zone. The balances for air mass flow, contaminant mass flow, water vapour mass flow and heat flow are determined between zones and between zone and outer boundaries. The two zone models are especially useful for stratification and zoning strategies because of the typical vertical stratification of heat, contaminants or water vapour within these strategies. The aim of the zoning strategy is to have control of temperature, concentration or humidity over a certain volume of the room, while the rest of the room is left with less attention (2). The objective of this paper is to determine a practical two zone model for the air distribution methods of the zoning strategy.