[opacho]

Hello everyone I am studying as chemical engineer and have a project about Sulfire Dioxide . I calculate all the necessary variables then write them on polymath program to solve its differantial equations and see their graphs. I'm sure I write correct equations since polymath says it's ready to solve. But I am having errors. Here is the codes

d(x)/d(w) = -(ra)/fao #
d(P)/d(w) = (-1.12*10^(-8)*(1-0.055*x)*T)*(5500*visc+2288)/P #
d(T)/d(w) = (5.11*(Ta-T)+(-ra)*(-deltah))/(fao*(sum+x*dcp)) #
Ta = 1264.67 #
visc = 0.090 #      
fao = 0.188 #
k = 3600*exp(-176008/T-(110.1*ln(T))+912.8 ) #
dcp = -1.5625+2.72*10^(-3)*T-7.38*10^(-7)*T^2 #
sum = 57.23+0.014*T-1.94*10^(-6)*T^2 #
deltah = -42471-1.563*(T-1260)+0.00136*(T^2-1260^2)-2.459*10^(-7)*(T^3-1260^3) #
T(0)=1400 #
P(0)=2
x(0)=0
w(0)=0
w(f)=28.54
thetaso= 0 #
Po= 2 #
thetao= 0.91 #
eps= -0.055 #
R= 1.987 #
ra= If (x<=0.05) then (-k*(0.848-0.012/(Kp^2))) else (-k*((1-x)/(thetaso+x))^0.5*(P/Po*Pao*((thetao-0.5*x)/(1+eps*x))-((thetaso+x)/(1-x))^2/(Kp^2))) #
Kp=exp(42311/(R*T)-11.24) #
Pao= 0.22 #

Error is 'Zero Dominator not allowed 12/ Kp^2' . If anyone know Polymath program please help me where do I make mistake ?

[daf44]

Maybe the problem is that you initialize x(0), W(0) and thetaso with 0. Instead you should initialize them with some very small value, for example 10^-16