Development of a simpli"ed technique of modelling four-way ceiling air supply diʹuser

Computational 2uid dynamic (CFD) tools have been used extensively in the prediction of air2ow in indoor environment. However, it is important to understand that the accuracy of such simulation is aʹected by a number of factors depending on micro- or macro-level of modelling. It is in the interest of this paper to study, in micro-level modelling, the impact of various description of air supply diʹuser modelling on the accuracy of the air2ow prediction. Air supply diʹuser can be modelled in a number of diʹerent ways. Each technique can result in diʹerent air2ow pattern around the diʹuser and in the macro-environment. This paper investigates "ve diʹerent types of air supply diʹuser modelling techniques. It compares the throw pro"le of each of these diʹuser models against the measured pro"le in rooms of three diʹerent sizes. A diʹuser modelling technique that uses the RNG k– turbulence model has been successfully developed. It is simple and yet without compromising on the accuracy of the predicted results