Mesh Techniques And Uncertainty For Modelling Impulse Jetfans

This study presents the numerical modelling of a jetfan stream using an open source Computational Fluid Dynamics (CFD) software named Fire Dynamics Simulator (FDS)6.5.2. The software is based on an accurate turbulence model named Large Eddy Simulation (LES) along with a structure mesh to discretize the numerical domain.

This research is focussed on the feasibility and accuracy of modelling jetfans using FDS, where a simplified three-dimensional model is built to represent a single jetfan in an open-deck car park, to compare the air jet downstream of the jetfan using various mesh techniques.

This study included a verification of the model by solving a single jetfan using a relatively fine mesh and comparing it to a coarser mesh using various mesh techniques. The results obtained show that the behaviour of a jetfan can be resolved using FDS but it requires a significant number of grid points which makes it unfeasible to model a medium to a large size car park.