Engineering tools · Independent perspective
What Cat Lab can tell you today
How to use the first reactor module, understand its limits, and connect its calculations to a practical engineering question.
Nate Shakouri · September 2026 · 3 minute read
Start with one well-defined model
The current Cat Lab module characterizes a cylindrical packed bed at a single operating state. It connects geometry, catalyst inventory, gas flow, nominal contact times, space velocity, and optional Ergun pressure drop.
The calculator uses explicit input units and canonical SI calculations. Results expose their equations, prerequisites, assumptions, and physical checks so a user can examine the basis of a number.
Try a simple comparison
Load the illustrative example and change the bed diameter from 10 mm to 20 mm, keeping length and flow unchanged. The calculated bed volume increases by a factor of four and the superficial velocity decreases by a factor of four. These follow from the cross-sectional area of a cylinder.
This is an example of a geometry-and-flow relationship. It helps explain a tradeoff, but it does not establish reaction performance, catalyst lifetime, or an optimal design. The example inputs are demonstrations, not a gas-property dataset or a validated product configuration.
Keep the scope of the answer visible
The current module assumes ideal-gas behavior and a nonreacting, single-state bed. The optional Ergun estimate uses sphere packing and constant properties. Physical stream balances remain not checked when independent inlet and outlet evidence is absent.
A calculated result can be mathematically consistent while the chosen model is insufficient for a particular application. Inspect the Engineering Review and the assumptions attached to the result before interpreting it.
The direction beyond the first module
My long-term aim for Cat Lab is a connected scientific computing environment: reusable models, data analysis, reproducible projects, and eventually more capable simulation. The current release has one reactor module; those broader capabilities are a development direction.
The principle should remain the same as the software grows: make the model inspectable, state its scope, and test each numerical method against appropriate evidence.