What is the convection section?

• A. Top Section
• B. Bottom Section
• C. Middle Section
• D. Exterior Section

Answer: (A)

The convection section is the upper portion of a fired heater or boiler where heat transfer to the tubes occurs mainly by the flow of hot combustion gases over them (convection), rather than by direct radiant heat from the flames. Radiant heat acts primarily in the bottom part, so as the gases rise and pass through the upper section, their heat is transferred to the tubes via convection. This is why the convection section is described as the top section—the design places the convective heat-transfer area above the radiant zone to efficiently extract heat from the flue gases.