Question

The difference between recuperators and regenerators is primarily in their:

• A. Operating temperatures
• B. Heat transfer mechanisms
• C. Continuous versus intermittent operation
• D. Application industries

Hint:

Recuperators = Continuous operation; Regenerators = Intermittent operation using thermal storage. That’s the key operational difference.

Answer 1

The Correct Option is C

Step 1: The primary difference between recuperators and regenerators lies in the way heat exchange occurs over time. 
Step 2:

• Recuperators operate in a continuous mode where hot and cold fluids are separated by a solid wall and heat is transferred steadily as they flow on opposite sides.
• Regenerators, on the other hand, operate in an intermittent or cyclic mode. A thermal mass (like ceramic) stores heat from hot gases during one cycle and transfers it to cold gases in the next.

Step 3: Although both devices aim to recover waste heat and improve thermal efficiency, their operational behavior distinguishes them most significantly. 

Why the other options are incorrect:

• (A) Both can be designed for high-temperature operations.
• (B) The basic mechanism—heat exchange—remains the same in principle.
• (D) Both are used across various industries depending on process needs, not limited by application type.