> restart;#'therm_eq7.mws'.22-6-00.

Chapter 7: Set of pre-written equations available.

Definition of molar fraction

> eq7_1:=x[i]=n[i]/Sum(n[i],i=1..C);

`:=`(eq7_1, x[i] = `/`(`*`(n[i]), `*`(Sum(n[i], i = 1 .. C))))

Mmixing entropy

> eq7_17:=DS[mixing]=-n*R[u]*Sum(x[i]*ln(x[i]),i=1..C);

`:=`(eq7_17, DS[mixing] = `+`(`-`(`*`(n, `*`(R[u], `*`(Sum(`*`(x[i], `*`(ln(x[i]))), i = 1 .. C)))))))

Exergy flow through a pipe

> eq7_22:=psi=(h[t]-T0*s)[n[i]]+Sum(x[i]*(mu[i]-mu[i0]),i=1..C)[T0,p0];

`:=`(eq7_22, psi = `+`((`+`(h[t], `-`(`*`(T0, `*`(s)))))[n[i]], (Sum(`*`(x[i], `*`(`+`(mu[i], `-`(mu[i0])))), i = 1 .. C))[T0, p0]))

Exergy to get a flow of a pure substance from the ambient

> eq7_24:=psi=-R[u]*T0*ln(x[i0]);

`:=`(eq7_24, psi = `+`(`-`(`*`(R[u], `*`(T0, `*`(ln(x[i0])))))))

Raoult's law for the biphasic equilibrium af sustance i in ideal mixtures

> eq7_50:=x[vap,i]/x[liq,i]='p[v||i](T)/p';

`:=`(eq7_50, `/`(`*`(x[vap, i]), `*`(x[liq, i])) = `/`(`*`(p[v || i](T)), `*`(p)))

WARNING. A list of all variables follows, to copy and paste to the save command (after Maple7 there is no saving all). CAUTION: After pasting all, I must MANUALLY delete system variables: like RealRange_...

> sort([anames()]);

[_Remember, eq7_1, eq7_17, eq7_22, eq7_24, eq7_50, lasterror, lastexception, ln, `type/SymbolicInfinity`]

> save eq7_1, eq7_17, eq7_22, eq7_24, eq7_50, "../therm_eq7.


> m":