Why the output speed of a fluid coupling is always lower than the input speed?
To enable the fluid to flow from impeller to rotor it is essential that there is a difference in ‘Head’ between the two and thus it is essential that there is a difference in speed known as slip, between the two. Slip is an important and inherent characteristic of a fluid coupling resulting in several desired advantages. As the slip increases, more and more fluid can be transferred from the impeller to the rotor and more torque is transmitted.
