γ=57*(10^6);
ro=8000;
c=300;
σ=5.67*(10^(-8));
To=20;
mm=0.001;
d=0.1mm;
o=Pi*d;
Sk=((Pi*(d^2))/4);
proud=10;
Jecko=(proud/Sk);
λ=400;
ϵ=0.2;
α=6;
QV=((Jecko^2)/γ)-(o/Sk)*(α*(T[x,t]-To)+ϵ*σ*((((T[x,t]+273))^4)-(((To+273))^4)));
rce=ro*c*D[T[x,t],t]==D[λ*D[T[x,t],x],x]+QV;
poc=T[x,0]==To;
okr1=T[0,t]==To;
xmax=5mm;
okr2=T[xmax,t]==To;
tmax=0.1;
rcecelkem={rce,poc,okr1,okr2};
res=NDSolve[rcecelkem,T[x,t],{x,0,xmax},{t,0,tmax}][[1]]
Plot3D[T[x,t]/.res,{x,0,xmax},{t,0,tmax}]