[Scorael]

I hope I posted on the right place.

I'm an electrical engineering undergrad doing a project on fuel cells. I have been using a book to aid me in this but the author did not clarify how she arrived at several equations. I hope the equations might ring a bell for someone in the forum.

In one example the partial pressure of gases in the fuel cell system was to be determined. The equation goes like this:-

pp_H2= 0.5*((P_H2)/(exp(1.653*i/T^1.334)))-P_H2O

pp_O2=((P_air/exp(4.192*i/(T^1.334))-P_H2O

Where pp_H2 is the partial pressure of hydrogen in the system, pp_O2; the partial pressure of oxygen in the system, P_H2; the pressure of hydrogen being pumped into the system, P_air; is the pressure of air being fed into the system, i; is the current being drawn from the system, T; temperature of the system (Kelvin) and P_H2O; the water saturation pressure.

From my understanding the 0.5 is related to the reaction of hydrogen and oxygen to form water but I am unfamilliar with the origins of numbers 1.653, 4.192 and 1.334. Both equations appear to be Dalton's Law but I am unsure about that.

Hope someone can identify how the author came about with these equations. Thanks for any help given.

[damankhaira]

I guess the book u r refering is 'PEM modeling and simulation using MATLAB' by colleen spiegel.
this is most erroneous book to refer to as nothing is explained much. I have been refering to this also for my project.
I also have the same doubt as you but after searching i am not able to find a satisfactory answer.