What are you evaporating from what?
Got to be carefull with materials used, esp metal radiators as you have in your diagram, basically anything metal should be taken out, thats why all sci equiptment is glass.
So is this a distillation aparatus or just something to dry a substance? to remove water from a substance?
I reserve opinion untill you put up an exact definition and step us through how its supposed to work.
-ApprenticeCook