Performance figure for turbo machines

The coefficient of performance is a dimensionless number and characterizes the performance of turbomachines : ${\displaystyle \lambda }$

• for work machines (e.g. pumps , compressors ):

${\displaystyle \lambda ={\frac {\psi \cdot \varphi }{\eta }}}$

• for power machines (e.g. wind turbines , turbines ):

${\displaystyle \lambda =\psi \cdot \varphi \cdot \eta }$

each with:

• the number of prints  ${\displaystyle \psi }$
• the flow rate  and ${\displaystyle \varphi }$
• the efficiency  . ${\displaystyle \eta }$

literature

• Willi Bohl: Turbo machines 1, structure and mode of operation . Vogel, Würzburg 1998, ISBN 3802317378 .