Final answer:
The statement is true as regenerators use a wall to separate hot and cold fluids and transfer heat by conduction through the wall as well as by convection to and from the wall.
Step-by-step explanation:
The statement is True: In regenerators, hot and cold fluids are separated by a wall, and heat is transferred by conduction through the wall and convection to and from the wall. Heat transfer encompasses three main mechanisms: conduction, convection, and radiation. In the case of regenerators, the heat transfer by convection occurs due to the macroscopic movement of the fluids where the warmer material rises and the colder material sinks. Additionally, heat is conducted through the wall separating the hot and cold fluids. The whole process of heat transfer in regenerators aligns with the law of conservation of energy, ensuring that energy is neither created nor destroyed, simply transferred from one part to another.