An Eulerian multidimensional model for a cylindrical two-phase dispersed particle jet is proposed and compared with experimental data. The averaged equations of mass and momentum are solved for each phase and the turbulent kinetic energy equation is solved for the continuous phase. The phase distribution is controlled by the interfacial forces and the Reynolds stress gradient. The two fluid model averaging procedure developed by Reeks (1992) results in a turbulent diffusion force. This force is constituted for the case of homogeneous turbulent flow. Furthermore, it is proposed that the eddies interact primarily with those particles that are smaller than them, i.e., only bigger eddies can trap particles and deflect their path. The constitutive relations for the turbulent kinetic energy of the continuous phase consists of a κ-ε model which has been modified for two-phase flows. Once the constitutive relations have been defined, the two-fluid model is implemented in a computational fluid dynamics code. The results are compared against experimental data for an air jet with 39μm glass particles. Because the fluid flow around these particles is well understood, they represent a good starting point for the development of a two-phase turbulence model. The particles are assumed to follow a drag law consistent with Oseen's equation. Furthermore, these particles have very small turbulent wakes so they produce negligible additional turbulence. Their effect on turbulence modulation is primarily dissipative due to viscous shear in the flow field around them. In the vicinity of the jet source the time constant of the glass particles is significantly larger than the time constant of the turbulent eddies. Therefore, the trajectories of the particles are quite different from those eddies and the turbulent diffusion force may be validated at conditions where the classical gradient-diffusion approximation is not very good. It has been shown that the present model is equivalent to Taylor's gradient-diffusion equation when the particle-gas flow approaches turbulent equilibrium. Good agreement between the model and the data is obtained. The sensitivity of the results to the turbulence time constant definition is discussed. Furthermore, the effect of turbulence anisotropy is also considered.
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