boundary integration
 

Hello
I'm trying to use boundary integration in Comsol to find the mass flux (kg/sec) of methane coming out of a combustion unit. However the answer I get is higher than inlet methane which gives negative conversion. I'm wondering if there is any other precise way of integrating a data set of (x,y) which has very small y values.
thanks

If small y values, and therefore floating point precision is your problem, can you not simply scale the variable up before doing the integration?

Evo2.