Inquiry of Particle initial condition setup
 

Is it possible to setup a certain height of particle in a box as a initial condition in ANSYS CFX? It is to see the movement of particle from 0 to a certain velocity by bottom inlet air nozzle.

If you are doing Lagrangian particle tracking then you can define particle injection regions anywhere you like. If you are doing rigid body 6DOF models then you can also define the starting point to be where ever you like.

If you would like more assistance please describe what you are trying to do more thoroughly.

There is no movement of sand in CFB boiler in the beginnig of combustion. So, I want to simulate this. Before running CFB boiler sand has been located in boiler a certain height. The purpose of this to get sand erosion rate on CFB boiler and cyclone walls.

Please define your acronyms. I assume CFB means circulating fluidised bed - but remember not everybody works in your industry and knows all the acronyms.

This sounds like a complex simulation. You need to start with a fluidised bed combustion model - which is a complex model in itself. Once you have this model working you can add sand, presumably as lagrangian particles, and get the sand trajectories and wall erosion rates. There are going to be many challenges in getting this simulation working, I hope you are an experienced CFD person with plenty of time for careful model development and validation.

Sorry for using acronyms and thank you for your help. I wanted to solve errosion first and then combustion later but I will try as your advice.

Whether you do combustion or erosion first is not important. The important thing is that you introduce the complex physics one step at a time so you can get it working properly before you add the next bit of complex physics.

So I suspect you should start with a fluidised bed simulation. When that is running successfully you can add sand particles and start erosion modelling. And when that is running successfully you can add combustion.