A Numerical Investigation of Internal and External Two-Phase Flows of a Rotating Disk Atomizer

In this paper, a numerical study has been carried out to model and simulate the air-water two-phase flows in and around a rotating disk atomizer, which uses multiple nozzles to breakout the water and forms droplets. The physical problem was simulated with an Eulerian multiphase model. The realizable two-equation turbulence model was used for the turbulent flow. The governing equations were solved with a finite volume based numerical method. The rotary frame approach was used to deal with the spinning disk. Numerical simulation was conducted in a disk rotational speed range of 1000 to 10000 rpm, a liquid feed flow rate range of 100 to 150 gpm. Both uniform and non-uniform liquid distribution conditions were considered. Detailed results about flow velocity and volume fraction fields inside and outside of the atomizer are presented and discussed. It was found that when liquid is nonuniformly distributed through the distributors, some of the nozzles could reach flooding conditions at lower rotational disk speed and liquid feed volume flow rates, as compared to uniform distribution cases.