کلیدواژهها
|
vortex tube, air separator, separation process, turbulence model, numerical simulation.
|
چکیده
|
The air separators are used to provide safe, clean and appropriate air to the helicopter’s engine. In this
operational study, the separation process inside a Ranque-Hilsch air separator cleaning system has been investigated
to analyze the impact of choosing the appropriate turbulence model for predicting the separation process inside the
air separator. This research is directed towards presenting a computational fluid dynamic explanation performed on
a counter-flow air separator using air at different magnitudes of air flow fraction and applying different turbulence
models. In a numerical investigation of counter-flow air separator, air has been chosen and its vortex separation phenomenon
has been analyzed as a function of flow fraction. Furthermore, a numerical analysis to compare the outputs
of a seven equation RSM turbulence model applied for the study of vortex separation of a counter-flow air separator
with some two-equation turbulence methods, namely, k-ε and k-ω model as well as LES has been presented. All of the
turbulence numerical methods are seen to present and predict the same flow pattern inside an air separator, but, with
various details. The results show that among the tested methods the RSM creates the most accurate separation pattern.
The numerical results are validated by some available experimental data with good agreement.
|