Simulating Rough Wall Pipe Flow in OpenFOAM with interFoam

 In OpenFOAM, you can simulate rough wall effects in your pipe flow simulations using the roughWall function object. This function alters the logarithmic law of the wall to account for the increased drag caused by the roughness.

Here's a general approach to implementing rough walls with interFoam:

 * Patch Identification: Identify the wall patches in your geometry where you want to apply roughness.

 * roughWall Function Object: Include the roughWall function object in your cht dictionary file. You'll specify the roughness height (k) and kinematic viscosity (nu) within this function.

 * Boundary Conditions: Set appropriate boundary conditions for the wall patches using the identified function object.

Remember to consult the OpenFOAM documentation for detailed instructions and code examples on implementing the roughWall function object.