# Multiple Char Reactions for Coal Combustion

## Simulation of Multiple Char Reactions for Coal Combustion

In this tutorial, we provide guidelines for modeling and simulation of coal combustion or gasification with multiple char reactions. We use finite-rate/eddy-dissipation model in our simulations.

### You will also learn how to do the following through this tutorial:

• Solving multiple char reactions for coal combustion employing discrete phase model
• Modeling reactions occurring during combustion by activating the finite-rate/eddy-dissipation model
• Setting up the solver and solving the problem
• Also, Post-process the resulting data
• Adding the radiation model and investigate its effect on the reaction temperature.

### Problem Description of Coal Combustion

We consider a simple 10 m *1 m 2D duct as a coal combustion system. In our simulation, we only need to model half of the domain width due to the symmetry. Also, we have two inlet streams. The first one is a high-speed stream near the center of the duct with the velocity of 50 m/s and span of 0.125 m. The other stream enters at 15 m/s and spans 0.375 m. The temperature of both streams is 1500K. The mass flow rate of coal particles is 0.1 kg/s. Coal particles enter the combustor near the center of the high-speed stream. The temperature of the wall is 1200K. Based on the inlet dimension and the average inlet velocity, the Reynolds number is approximately 100,000. Therefore, the flow is turbulent.