What is the primary function of an APU accumulator?

The primary function of an APU accumulator is to store hydraulic energy. In aviation, particularly in aircraft systems, the Auxiliary Power Unit (APU) serves multiple purposes, one of which is to provide hydraulic power for various systems. The accumulator plays a critical role in this task by storing hydraulic fluid under pressure.

When the hydraulic system demands more power than what the APU can provide continuously, the accumulator releases the stored hydraulic energy to meet this demand. This ensures that there is a steady supply of hydraulic pressure available, which is essential for operations such as landing gear deployment, flight control systems, and other hydraulic-driven components. By effective storage and release of hydraulic energy, the accumulator contributes to the overall reliability and efficiency of the aircraft's hydraulic system.

While other functions like controlling rotor dynamic loads, maintaining temperature control, and providing fuel efficiency are important in different contexts, they do not align with the specific role of an APU accumulator, which is focused on the storage and management of hydraulic energy. This distinction is crucial for understanding the various components and systems involved in aircraft operations.