$macro Cp(k, T) R*(pcoeff(k, "A1H") + pcoeff(k, "A2H")*T + pcoeff(k, "A3H")*T**2 + pcoeff(k, "A4H")*T**3 + pcoeff(k, "A5H")*T**4)$(T gt 1000 and T lt 6000) + (pcoeff(k, "A1L") + pcoeff(k, "A2L")*T + pcoeff(k, "A3L")*T**2 + pcoeff(k, "A4L")*T**3 + pcoeff(k, "A5L")*T**4)$(T gt 200 and T le 1000) $macro HT(k, T) R*T*(pcoeff(k, "A1H") + pcoeff(k, "A2H")*T/2 + pcoeff(k, "A3H")*T**2/3 + pcoeff(k, "A4H")*T**3/4 + pcoeff(k, "A5H")*T**4/5 + pcoeff(k, "A6H")/T)$(T gt 1000 and T lt 6000) + (pcoeff(k, "A1L") + pcoeff(k, "A2L")*T/2 + pcoeff(k, "A3L")*T**2/3 + pcoeff(k, "A4L")*T**3/4 + pcoeff(k, "A5L")*T**4/5 + pcoeff(k, "A6L")/T)$(T gt 200 and T le 1000) $macro ST(k, T) R*(pcoeff(k, "A1H")*log(T) + pcoeff(k, "A2H")*T + pcoeff(k, "A3H")*T**2/2 + pcoeff(k, "A4H")*T**3/3 + pcoeff(k, "A5H")*T**4/4 + pcoeff(k, "A7H"))$(T gt 1000 and T lt 6000)+ (pcoeff(k, "A1L")*log(T) + pcoeff(k, "A2L")*T + pcoeff(k, "A3L")*T**2/2 + pcoeff(k, "A4L")*T**3/3 + pcoeff(k, "A5L")*T**4/4 + pcoeff(k, "A7L"))$(T gt 200 and T le 1000) Sets i fatia_rel_ignicao /1*3/ ka atomos /H hydrogen,O oxygen/ ; Sets k species /O, O2, H, H2, OH, H2O, HO2, H2O2/ ; Sets j polynomial coefficients /A1H*A7H, A1L*A7L/ jcp(j) cpcoefficients /A1H*A5H, A1L*A5L/ jh(j) enthcoefficients /A1H*A6H, A1L*A6L/ ; Table pcoeff(k, j) $include Pol.txt ; Parameter R gasconstant Jmol-1K-1 /8.3144621/ ; Positive Variables yi(i), D(i), Ti(i), TL(i), TH(i), DGi(I) ; Free Variables Dt ; Equations yimeio, TLin, THTL(i), TLmeio, THmeio, ytoti, DeltaGi(i), C(i), Ct; yimeio.. yi("2")=E=0; TLin.. TL("1")=E=298; THTL(i).. TH(i)=E=TL(i+1); TLmeio.. TH("1") =E= Ti("2"); THmeio.. TL("3")=E= Ti("2"); ytoti.. sum(i, yi(i))=E=1; DeltaGi(i).. DGi(i) =E= HT("H2O", Ti(i)) - HT("H2", Ti(i))-0.5*HT("O2", Ti(i))-Ti(i)*(ST("H2O", Ti(i)) - ST("H2", Ti(i))-0.5*ST("O2", Ti(i))); C(i).. D(i) =E= -yi(i)*DGi(i) - 40*(TH(i)+TL(i) - 2*Ti(i)) + 40*Ti(i)*log(TL(i)*TH(i)/Ti(i)**2); Ct.. Dt=E=sum(i, D(i)); model Ignition / yimeio, TLin, THTL, TLmeio, THmeio, ytoti, DeltaGi, C, Ct/; solve Ignition maximizing Dt using NLP;