Noun
turbomachinery (uncountable)
Turbomachines collectively.
The Design of High-Efficiency Turbomachinery and Gas Turbines, David Gordon Wilson, P.15 By this time, the comparably efficient Tesla turbine was over 60 years old. Source: Internet
A very high claim for rotor efficiency (as opposed to overall device efficiency) for this design was published in 1991 titled "Tesla Turbomachinery". Source: Internet