Air Distribution in a Room with an Active Chilled Beam - and a Comparison with other Ventilation Systems

Active chilled beam cooling is a solution with an efficient use of space due to the high heat capacity of water used as heat transfer medium. This paper describes the prediction of the room air distribution in a room with an active chilled beam. It also shows a design chart that makes it possible to assess variables such as air quality, air velocity and the temperature gradient as a function of flow rate and temperature difference in the supply system and this paper gives the limits for the use of the system.

The paper shows that an active chilled beam system can generate a thermal comfort level at a given heat load and heat load distribution that can be compared with the thermal comfort obtained by the different mixing ventilation systems. The air distribution is dependent of the heat load distribution, and the system has a limited capacity with respect to fresh air supply. The system is compared with seven other air distribution systems. The paper is based on both full-scale measurements and CFD predictions.