At present, turbochargers  RHC62 12552738 are widely used in the automotive field. Although 

each manufacturer has its own characteristics in product development, and the characteristics 

of development vary according to their use, the characteristics of high efficiency, miniaturization, 

and large capacity are the same. Especially for trucks, industrial and marine superchargers, the 

high pressure ratio supercharger has been one of the key development trends recently. As a 

product for automobiles,there are still strong requirements for improving its low-speed 

performance and acceleration following.

Due to the increase in the specific power of diesel engines and the improvement of installation

convenience, the requirements for miniaturization and large capacity of turbines and compressors

have been increased. In addition, it is important to improve the acceleration performance of

automotive superchargers. The reduction of the turbine diameter has a great effect on the moment 

of inertia of the turbocharger rotor.

For this reason, a runoff turbine with a high specific speed was developed in response to the

requirements of miniaturization and large capacity, which reduced the inlet diameter and 

increased the outlet diameter so that the flow rate could be increased. This high-speed turbine 

is used inautomotive turbochargers and is smaller in shape and lighter than conventional 

turbines.

Recently, not only run-of-the-flow turbines with high specific speeds have been developed, but 

also mixed-flow turbines. In this way, the flow rate of the mixed-flow turbine is approximately 14%

higher than that of the leakage wheel of the high-speed type, and the efficiency is also increased 

by several percentage points. This achievement has been applied to marine diesel runoff wheels 

and truck turbines.