The flow rate in thermal plumes are influenced by many factors. Influence by enclosing walls is one of them. This article presents simple symmetry considerations to calculate the flow rate in such flows, and they are experimentally verified as regards wall plumes. When the flow takes place near to enclosing walls the entrainment is influenced and a reduction of the flow rate is observed. For displacement ventilation this means a reduction of the stipulated necessary ventilating air flow rate when an air quality based design method is used.
Zonal models are a promising way to predict air movement, in a room with respect to comfort conditions and gradient of temperature, because they require extremely low computer time and may be therefore rather easily included in multizone air movement models. The main objective of this paper is to study the ability of the zonal models to predict the thermal behaviour of air in case of natural convection coupled with a radiator. First, we present simplified two zone and five zone models.
In this paper information is provided about ways to model the boundary conditions near the radiator for use in the flow simulation program. Due to lack of time the modelling is restricted to the thermal behaviour of a single plane radiator as selected in 'R.I. 1.4 : Selection of radiator'. Ways to model the flow near the radiator with e.g. hot and cold wall jets have not been investigated.
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