In[]:=
ClearAll[x,y,t,u,Ω1,Ω2,Ω3,Ω4,Ω5,ΩT,y1,P1,P2,BC,sol]​​Ω1=Rectangle[{-2,-2},{2,2}];​​BC:=DirichletConditionu[t,x,y]=
0
t<0
5*t​​50
0≤t≤10​​10<t
,(x-2&&1.75≤y≤2)||(x2&&-2≤y≤-1.75)​​IC:=u[0,x,y]0​​heatEquation:=D[u[t,x,y],t]-10
2
∇
{x,y}
u[t,x,y]0​​sol=NDSolveValue[{heatEquation,BC,IC},u,{t,0,150},{x,y}∈Ω1]​​ContourPlot[sol[5,x,y],{x,y}∈Ω1]​​​​
NDSolveValue
:The boundary condition DirichletCondition
0
t<0
250t
(10<t)(0≤t≤10)
0
True
,(x-2&&1.75≤y≤2)||(x2&&-2≤y≤-1.75) cannot be parsed and will be ignored.
Out[]=
InterpolatingFunction
Domain: {{0.,150.},{-2.,2.},{-2.,2.}}
Output: scalar

Out[]=