Can any one help me to create a model for a confined
rectangular space in which left wall is hot and
the right wall is cold. Top and bottom walls are insulated.
No radiation outside or inside the wall.
Many software allow to create, but I tried tried tried
with Heat Heat2D.
Isn’t this what you want? In the previous version, you didn’t put an insulator on the right, which of course leads to thermal leakage and cause convection outside the box. I added an insulator to the right and there is no convective current outside.