Heat confinement in tunnels between two double-stream twin-jet air curtains

Heat confining in tunnels by means of double-stream twin-jet (DS-TJ) air curtains was studied numerically to simulate the behavior of an experimental facility built for research and design purposes. The results of 2D and 3D simulations were compared. The axial distributions of mean velocity, turbulent kinetic energy and Reynolds stresses were investigated over the entire jet flow. The temperature field obtained by numerical simulations was compared with the results of experiments. The simulations show that the flow structure within the domain is essentially two dimensional. Radiation effects from the lateral walls in the 3D case induce higher temperatures within the confinement zone. Both the 2D and 3D approaches overestimate the temperature in the domain with respect to experiments.