In a recuperative air preheater, the heat is transferred________?
Aheat is transferred by bleeding some gases from furnace
Bby direct mixing,
Cnone of the above
Dfrom a metal wall from one medium to another
Efrom heating an itermediate material and then heating the air from this material
Correct answer
D. from a metal wall from one medium to another
Explanation
The correct answer is from a metal wall from one medium to another.