(*Free convection*)
β=(1/(50+273.));
g=9.81;
Dchar=0.9;
ΔT=80-20;
visc=17.88*(10^(-6));
Pr=0.7;
Gr=((g*β*ΔT*(Dchar^3))/(visc^2));

Pr*Gr
c=0.135;
n=(1/3);
Nu=c*(((Pr*Gr))^n)

λ=0.02808;
α=((Nu*λ)/Dchar)

S=0.9*0.8;
P=α*S*(80-20)

(*Inside Tube, turbulent*)

Dchar=0.5;
v=0.5;
visc=4.73*(10^(-7));

Rey=((v*Dchar)/visc)

Pr=2.99;

Nu=0.023*(Rey^(4/5))*(Pr^0.3)

λ=0.640;
α=((Nu*λ)/Dchar)

lenght=20*1000.;
S=Pi*Dchar*lenght;
PowerLosses=α*S*(60-59)

(*around the plane*)

v=2;
Dchar=0.8;
visc=15.06*(10^(-6));

Rey=((v*Dchar)/visc)

Nu=0.032*(Rey^0.8)

λ=0.0258;

α=((Nu*λ)/Dchar)