## Fluids

#### Defining solid phase in Eulerian multiphase simulation

• Hesam062
Subscriber
Hi everyonenI am doing chemical looping gasification in fluidized bed using Eulerian-Eulerian approach.nI need to define a certain amount of a material (biomass) as a solid phase (0.2g).nCould you guide me how can I define the exact amount of the material in computational domain?.Thanks, nHesamnn
• DrAmine
Ansys Employee
Mass of the phase (volume report) should match the mass you want. You should then deduce the required volume fraction from whole volume and density of your material if everything is mixed homogeneously. Even if only certain part of the device would contain the solid: you need to know that volume.n
• Hesam062
Subscriber
I know the volume of bed before fluidization and also the mass and density of solid. Do you mean the mass of solid can be defined in fluent by patching the volume fraction of that solid (calculated from solid volume divided by initial bed volume) in initial bed volume?nIs there any way in Eulerian-Eulerian approach to inject the second solid phase into fluidized first solid phase?n
• Rob
Ansys Employee
You can transfer mass from one phase to another. Or do you want to add another phase into the region where the fluidised bed it? n
• DrAmine
Ansys Employee
I do not understand your second question. Regarding patching: yes you need to know how the phases are distributed to know the volume and then you can deduce the volume fraction to from whole particulate mass and volume they need to occupy!n
• Hesam062
Subscriber
Yes I have two solid phase (Sand: initially patch into bed and then I wanted to define an exact amount of mass of second solid phase into CFD domain).nThanks . Regarding second question: I was thinking to use the injection tools in fluent to inject second solid phase into CFD domain.nn
• Hesam062
Subscriber
Although both DEM and DDPM are Lagrangian _ Eulerian Method, I am kind of confused about Discreet Element method (DEM) and Dense discreet Phase Model (DDPM) approaches. Are they the same? I mean, are their setup approaches the same in Fluent?n n
• DrAmine
Ansys Employee
No. DEM is used to calculate particle particle and particle wall collision. DEM is a sub model of DDPM and DPM.n
• DrAmine
Ansys Employee
If using DDPM OR DPM particles will only interact with primary phase. That is default behavior.n
• Hesam062
Subscriber
ThanksnThere are DDPM and DPM in Fluent but I can?t find DEM setup.nhow is the setup of DEM in Fluent?.
• DrAmine
Ansys Employee
You enable it under DPM Panel. Be aware DPM particles are always tracked with the primary phase.n
• DrAmine
Ansys Employee
Transient particle tracking will be then required.n