Temperature and velocity distributions for slot devices.

Depending on the demands regarding the size and location of the occupation zone and the need for outdoor air flow rates, different ventilation systems and air supply devices have to be used in different kinds of buildings. The occupation zone in a residential building can be dficult to define, as many different activities can take place. Furthermore the hrnishings of the room can change with time. The highest air velocities and the lowest air temperatures in the occupation zone will often occur close to inlet air devices. The importance of the location and selection of inlet air devices is exemplified by studying an air slot device for mainly residential use. The slot device was placed over a window at a height of 2.0 m above floor level. Both measurements and calculations of air velocity and temperatures are presented in the paper. From a thermal comfort point of view the device tested seem to give satisfactory performance only for air flow rates less than 4 l/s. The draught problem will increase with lower inlet temperatures. It is also shown that the internal heating in a device can be important with regard to thermal comfort. The factors that influence the relationship between outdoor and supply temperature are also discussed.