how make an iteration of a function in simulink?

Hi,

I would like to create a model in Simulink that would be an equivalent of the following code in Matlab:

T1(1)=400;
T2(1)=80;
Tp2=H2O_Sattdampfkurve_pvonT(T2(1));

p2(1)=Tp2(1,2);

h1(1)=1;
h2(1)=2;
delta_T(1)=T1(1)-T2(1);

%M1=400;
%M2=1000;

M1=200;
M2(1)=300;
A=700;
k=1000;
Q(1)=k*A*delta_T(1);

N=10;
delta_t=0.0000001;
t(1)=1;

%spezifische Kapazität für Wasser

%cp1=1.5*2.778/10000;
%cp2=0.0005;
cp1=1.5*2.778/1000;

%cp1=1.5*2.778/10000;
%cp2=H2O_IAPWS_cp([T2(1), p2(1)]);

cTp=H2O_IAPWS_cp([T2(1), p2(1)]);
cp2(1)=cTp(1,1);

%spezifische Kapazität

for j=1:3

for i=1:7

if Q<1
 break; 
end

h1(i+1)=h1(i)-(delta_t*k*A*delta_T(i))/M1;
T1(i+1)=T1(i)-(delta_t*k*A*delta_T(i))/(M1*cp1)

h2(i+1)=h2(i)+(delta_t*k*A*delta_T(i))/M2(j);
T2(i+1)=T2(i)+(delta_t*k*A*delta_T(i))/(M2(j)*cp2(i));

Q(i+1)=delta_t*M1*(h1(i)-h1(i+1));

Tp2=H2O_Sattdampfkurve_pvonT(T2(i+1));
p2(i+1)=Tp2(1,2);

cTp=H2O_IAPWS_cp([T2(1), p2(1)]);

cp2(i+1)=cTp(1,1);

if delta_T<40 
  break;
end

delta_T(i+1)=T1(i)-T2(i);
t(i+1)=t(i)+0.0000001;

end

M2(j+1)=M2(j)+5;

figure(1)

plot(t, T1, 'r')

hold on

plot(t, T2)
xlabel('t[s]');
ylabel('T[°C]');

figure(2)

plot(Q, T1, 'r')
xlabel('Q');
ylabel('T[°C]');

hold on

plot(-Q, T2)

end

Basicaly, I want to iterate two variables T1 and T2. I want to count the the next step value of both variables T1 and T2:

T1(i+1)=T1(i)-(delta_t*k*A*delta_T(i))/(M1*cp1)
T2(i+1)=T2(i)+(delta_t*k*A*delta_T(i))/(M2(j)*cp2(i));

Both variables are dependent on the delta_T(i) which is a difference between T1 and T2:

delta_T(i+1)=T1(i)-T2(i);

So the values T1(i+1) and T2(i+1) in the next time step depend on the difference between them in the prevoius time step. Which is quite tricky. I tried the For Iterate Block, but it doesn't work. However if I don't take into consideration the changing value of delta_T and I set it as constant it works correctly. The error is:

Simulink cannot solve the algebraic loop containing 'model2/Switch' at time 0.0 using the TrustRegion-based algorithm due to one of the following reasons: the model is ill-defined i.e., the system equations do not have a solution; or the nonlinear equation solver failed to converge due to numerical issues. To rule out solver convergence as the cause of this error, either a) switch to LineSearch-based algorithm using set_param('model2','AlgebraicLoopSolver','LineSearch') b) reducing the fixed step size. If the error persists in spite of the above changes, then the model is likely ill-defined and requires modification.