Numerical analysis of curved vane demisters in estimating water droplet separation efficiency

The present work deals with the numerical investigations of vaned demisters using a computational fluid dynamics tool to validate the presently adopted computational methodology. A vane demister profile identified from literature, on which experimental data is available, is chosen and water particles at the rated flow rate and distribution are injected. Discrete phase modeling approach with Rosin-Rammler size distribution is chosen for specifying the water droplet injection with a combination of break-up and/or coalescence option, along with few turbulence model recommended in the literature are tested for suitability. The walls of the demister are set to capture the water droplets impinging on them and will be removed from the numerical calculations. Various options within the solver are numerically tested to recommend an appropriate combination of solver setting. The results indicate that the Wave model is the best option among several other droplet breakup models available in the solver. It was observed that inclusion of Saffman lift force does not influence the results much. Spalart-Almaras model or Realizable k-ε model can be considered as a suitable turbulence closure for numerical prediction of vane separation efficiency in curved vane demisters.