Question 307General Subjects - Assistant Engineer

The correct answer is D) Conduction. When heat is being transferred from one side of an air compressor cylinder wall to the opposite side, the mode of heat transfer associated with that particular part of the overall process is conduction. Conduction is the transfer of heat through a solid material, in this case, the cylinder wall of the air compressor, without the involvement of any bulk motion of the material. The other options are incorrect because radiation involves the transfer of heat through electromagnetic waves, natural convection involves the transfer of heat by the movement of a fluid due to density differences, and forced convection involves the transfer of heat by the movement of a fluid due to an external force, such as a fan or pump.