[kkarkare]

Hello,

I've written a UDF to model the absorption kinetics of a metal hydride reactor. Before proceeding with my simulation, I would like to confirm the logical flow of my code, particularly the calculations for equilibrium pressure (\(P_{eq}\)) and the reaction rate.

:Background

The model is based on the modified van't Hoff equation for temperature-dependent equilibrium pressure. The reaction rate is dependent on the local temperature and the pressure ratio (\(P/P_{eq}\)). I am using a User-Defined Scalar (UDS) to track the hydrogen concentration in the hydride.

Request: Could someone please review the following snippet of my C code and confirm if the logic correctly implements these physics?

Specifically, I'd like to verify: The calculation of P_eq and the reaction rate. The correct use of Fluent macros to read temperature and pressure.The handling of the absorption condition (pressure > P_eq).

Here, the temperature will change based on the reaction, which will change the P_eq and eventually the reaction logically ends once the P_eq=Ps. So I don't know how to add a variable like temperature so that in Fluent, I will have the temperature change at each cell, which will be observed by the Simulation with the effects as well. I am not an expert in C code, more like a MATLAB guy. Please guide me through the code formatting and how to put this in Fluent for the simulation.

Thank you


Code Snippet: