Final answer:
The exhaust valve is a crucial component of the internal combustion engine. It opens during the constant-volume exhaust stage to expel combustion products, and it remains open during the isobaric compression stage to drive out the remaining combustion products.
Step-by-step explanation:
The exhaust valve is a component of the internal combustion engine that is responsible for allowing the combustion products to escape from the combustion chamber. When the exhaust valve opens, the combustion products are expelled, and there is almost no movement of the piston during this part of the cycle, so the volume remains constant. This stage is known as constant-volume exhaust. Most of the available energy is lost during this stage, as represented by the heat exhaust.
The exhaust valve remains open during the isobaric compression stage. In this stage, the remaining combustion products are driven out of the combustion chamber as the volume decreases from its maximum value to zero.