[mohamadalimirzaei1994]

I am simulation a cyclone with large particles (2mm) using DDPM. the problem is that particles tend to remain in the cylindrical part and most of the particles do not go to the conical part and just spin around in the cylindrical part (as it can be observed from solid volume fraction fig attached). I tracked the mass of particles in the domain and it is constantly increasing meaning that particles just remain in the body although the simulation is run for a long flow time (the 20s), and most of the particles have high residence time. Do you know what can cause such a problem??

[vinerm]

Particles are tracked based on net force and one of the important force is gravity. If gravity and operating density are not set, then particles will stay within the cylindrical chamber.

[mohamadalimirzaei1994]

Originally Posted by vinerm

Particles are tracked based on net force and one of the important force is gravity. If gravity and operating density are not set, then particles will stay within the cylindrical chamber.

gravity is on and the density of inert particles is specified as well, but still having the problem. I guess in cyclone downward motion of particles is mostly due to the downward gas flow near the wall, not just gravity.

Do you think setting restitution coefficient to below one (for example 0.9) might solve the issue??

[vinerm]

Gravity requires operating density to be set. And if density of continuous phase is lesser than the density of particles, then the density of continuous phase should be used as operating density.

[mohamadalimirzaei1994]

Originally Posted by vinerm

Gravity requires operating density to be set. And if density of continuous phase is lesser than the density of particles, then the density of continuous phase should be used as operating density.

is operating density, the one that is specified in reference values? this value is set based on continuous phase density.

[vinerm]

The values in the Reference Values have no effect on the case. The operating density is under Operating Conditions where operating pressure, its location, and gravity is set. You can see it under Boundary Conditions and Cell Zone Conditions.

[hossein76]

Originally Posted by mohamadalimirzaei1994

I am simulation a cyclone with large particles (2mm) using DDPM. the problem is that particles tend to remain in the cylindrical part and most of the particles do not go to the conical part and just spin around in the cylindrical part (as it can be observed from solid volume fraction fig attached). I tracked the mass of particles in the domain and it is constantly increasing meaning that particles just remain in the body although the simulation is run for a long flow time (the 20s), and most of the particles have high residence time. Do you know what can cause such a problem??

Hi, I want to do a 4-way coupling in Fluent. Can you help me? Thank you.(cyclone)

[alainislas]

I can help with your 4-way coupling cyclone simulation
alain.islas@gmail.com