Hydraulic fluids should generally have what characteristic to ensure efficiency?

Hydraulic fluids should generally have low viscosity to ensure efficiency in hydraulic systems. Low viscosity allows the fluid to flow easily through the system's components, enhancing the responsiveness and performance of hydraulic machines. When the fluid has lower resistance to flow, it helps to reduce energy losses and improves the overall efficiency of power transmission.

In hydraulic systems, it's crucial that the fluid can quickly fill the spaces within cylinders and move through valves without significant delay. Low-viscosity fluids provide better lubrication, contribute to cooler operating temperatures, and help in generating quicker actuation speeds. These characteristics are particularly important in applications where precise and rapid movement is required.

While high viscosity can sometimes be beneficial for specific applications requiring stability under high temperatures or pressure, generally, it can lead to slower operation and increased energy consumption due to higher resistance to flow. Inertia and compressibility are less relevant to the efficiency of hydraulic fluids in typical applications, as these terms relate more to the physical properties of the fluid rather than its flow characteristics.