Centrifugal Chiller Impeller Design and Performance
The impeller is the absolute heart of a centrifugal chiller, the rotating component that does the fundamental work of compressing the refrigerant. Its design and performance are directly linked to the chiller's efficiency, capacity, and stability. Here’s a comprehensive breakdown of the centrifugal chiller impeller: Core Function The impeller's job is to convert the rotational kinetic energy from the electric motor, steam turbine, or gearbox into pressure (head) and velocity in the refrigerant vapor. It accelerates low-pressure, low-density refrigerant gas from the evaporator outward and radially, increasing its pressure and temperature before it enters the diffuser and condenser. Key Design Characteristics & Types Modern centrifugal chillers almost exclusively use backward-curved, backward-inclined, or airfoil-shaped impellers. The old forward-curved designs are obsolete due to poor efficiency and