Untitled

%trovare Q
D1=0.3; %[m]
D3=0.4; %[m]
epsilon1=0.01*D1;
epsilon3=0.01*D3;
rho=1000; %[kg/m^3]
viscosita=1.141e-3; %[Pa*s]
za=80; %[m]
zb=30; %[m]
L1=300; %[m]
L3=900; %[m]
g=9.81; %[m/s^2]
v_test=serbatoi([.1 .1 .1]);
disp(v_test);
%Salvare la soluzione in v_sol
x0=[0.1 0.01 0.01];
v_sol=fsolve(@serbatoi,x0);
fprintf('v_sol1= %.4f m^3\n', v_sol(1));
fprintf('v_sol2= %.4f m^3\n', v_sol(2));
fprintf('v_sol3= %.4f m^3\n', v_sol(3));

function eqn=serbatoi(x)
D1=0.3; %[m]
D3=0.4; %[m]
epsilon1=0.01*D1;
epsilon3=0.01*D3;
rho=1000; %[kg/m^3]
viscosita=1.141e-3; %[Pa*s]
za=80; %[m]
zb=30; %[m]
L1=300; %[m]
L3=900; %[m]
g=9.81; %[m/s^2]
Q=x(1);
f1=x(2);
f3=x(3);
eqn= @(x) [1/sqrt(x(2))+4*log10(epsilon1/D1*1/3.7+1.255/((rho*x(1)/(pi/4*D1^2)*D1/viscosita)*sqrt(x(2))));  %fattore1
1/sqrt(x(3))+4*log10(epsilon3/D3*1/3.7+1.255/((rho*x(1)/(pi/4*D3^2)*D3/viscosita)*sqrt(x(3))));  %fattore3
za-zb-(4*L1/D1*x(2)*(x(1)/(pi/4*D1^2))*1/(2*g))-(4*L3/D3*x(3)*(x(1)/(pi/4*D3^2))*1/(2*g))]; %quota
end