Simulink Fuel Cell Stack - Partial Pressures

Within the Simscape Fuel Cell Stack Block, in the subsystem Partial Pressure, 3 functions are used are labeled PH2, PO2 and PH2O.

Above are the stated formulas accoridng to https://uk.mathworks.com/help/physmod/sps/powersys/ref/fuelcellstack.html

However, what are the partial pressures defined as? The PH2O in the model has a switch that sets its value to 1 when Temperature is below 100 degrees C. Partial pressures should all sum to a value of 1 therefore, how can the PH2O be 1 and the caluclated PH2 and PO2 values are considered neglibl when calculated according the the above formulas

Answer 1

[Juan Sagarduy]

Hi Matthew

My interpretation is that high utilization of H2 and O2 leads to these residual pressures pH2 and pO2 being very low or negligible. Which is likely the intended way of using the fuel cell.

Regards Juan