Experimental study of mixing in a closed room by doorway exchange flows.

We present a series of analogue laboratory experiments of the transient exchange flow between a room filled with warm air and a cold exterior following the opening of a doorway. Our experiments suggest that the time-scale for mixing the fluid in the room below the top of the doorway is independent of the door height. We then describe the steady-state two-layer stratification that is established when, in addition to the exchange flow, a localised heat source provides heat at the base of the room.

A comparison study of the effectiveness of three ventilation systems in purging pollutant using CFD.

A three-dimensional mathematical model to solve the mixing, displacement and vortex ventilation systems in the removal of pollutants with a thermal source is described. The study carried out to investigate the effectiveness of each of the individual ventilation systems showed that the vortex ventilation system performed better than the other two systems in providing moderate occupancy thermal comfort but very effective in purging pollutants away from a typical office room environment

Effect of interior partitions on the air movement and air quality in a room with mixing ventilation.

Working spaces in modem buildings are easily formed by interior partitions because these buildings have been designed and constructed as open spaces for flexibility. This could lead to an indoor environment which might be different from the intended design. In this study, the effect of partition on the indoor air quality in a model room has been investigated with different configurations such as the height of' partition and the gap between partition and floor.

Prediction of air flow distribution in rooms and associated pollutant transfers by the systemic approach.

The general strategy adopted in the development of a computational tool performing the identification of parametric models based on the Residence Times Distribution (Rm) theory is exposed. Two main aspects of the modelling procedure are presented: the structural discrimination of the various solution schemes, and the parameters estimation step. The structural model determination is solved by a stochastic procedure based on a Simulated Annealing algorithm, while the parametric identification is solved by a nonlinear deterministic procedure.

Forecast of the properties of a cold vertical wall jet coming from a fan coil.

The study of the flow in a room cooled by a fan-coil pointed out how the form of air flow and comfort could be influenced by the characteristics of the cold jet blowing out. It is based both on practical experiment and on numerical simulation using CFD code. Combining these methods allowed a large number of configurations to be studied, in association with different conditions for the appliance. Using the results in combination enabled a relation to be established between the problem data, the device characteristics and the comfort conditions obtained.

The influence of furniture on air velocity in a room - an isothermal case.

Using isothermal full-scale experiments and 3-dimensional CFD simulations it is investigated how normal office furniture influences the air movements in a mixing ventilated room. Two different types of inlets are used in the experiments and a set-up with normal office furniture is made. The set-up is simulated with one of the inlets where a volume resistance represents the furniture. The jet under the ceiling is investigated and it is found that the normal office furniture does not influence the air movements in the upper part of the room.

A method for prediction of room temperature distribution.

The heat sources in a room with upward air supply, can be ideally decomposed into some basic models. Based on searching of the solution of the basic models, then solving the varieties of practical problems, a simplified method for predicting vertical temperature distribution of room air is submitted in this paper. Calculated values of some practical examples agree satisfactorily with experiment results.