PHD Discussions Logo

Ask, Learn and Accelerate in your PhD Research

Question Icon Post Your Answer

Question Icon

How do I use CAL3QH software from the EPA?

The official user guide is comprehensive but overwhelming for a beginner. My goal is to model CO concentrations at a specific intersection from vehicle queues. I have my traffic data and geometry, but I'm struggling with how to properly structure the input files and define my sources and receptors in a way the model will accept. A conceptual overview of the workflow would be invaluable.environmental

All Answers (1 Answers In All)

By Shilpa A Answered 1 year ago

I've trained many researchers on this. First, don't open the software yet. Start by meticulously drawing your intersection geometry and identifying every lane as a separate "link" source. The most common early mistake is misdefining these links. Then, prepare your meteorology file: CAL3QH needs a specific, full-year data format. I would recommend using the AERMET processor to get it right. Finally, place your receptors strategically start with a simple grid at breathing height near the curb. Get this minimal setup running before adding complex features like signal timing. Treat your first run as a debugging exercise, not a final simulation.

 

Your Answer