HYDRODYNAMICS OF 2D GAS SOLID RISER

Abstract

Certain parameters such as Restitution co-efficient (e) , Specularity co-efficient (Ø) and velocity are varied to see the effect of these factors on the Hydrodynamics of 2D gas solid riser and also a comparative study is done between Euler-Euler and DDPM model. The various results were obtained: For e=1 (Ideal condition) the particle distribution into the riser is uniform and no cluster formation takes place and for realistic values (e = .8, e = .9 ) heterogeneous distribution of particles are obtained and cluster formation takes place at various locations into a column. The effect of specularity co efficient (Ø) is as if it varied from 0 to 1, gas, solid velocities near the wall decreases. Ø = 0 means perfect specular collisions and minimum resistance on the motion of particle (Free slip condition) and Ø = 1 means perfect diffuse collisions and maximum resistance on the motion of particles (No slip condition).The effect of air velocity is as, if we increases the velocity of air the distribution of particles in column is non uniform and channelling and bubbling also occurs. If we compare the models, DDPM model gives higher pressure into the riser and if we see the velocity profile, velocity of air near the wall is higher in Euler Euler model, as we go upward in riser velocity profiles becomes almost similar in both the models.