Editing Centrifugal compressor (section)

=== Inlet ===

The simplest inlet to a centrifugal compressor is typically a simple pipe. Depending upon its use/application inlets can be very complex. They may include other components such as an inlet throttle valve, a shrouded port, an annular duct (see Figure 1.1), a bifurcated duct, stationary guide vanes/airfoils used to straight or swirl flow (see Figure 1.1), movable guide vanes (used to vary pre-swirl adjustably). Compressor inlets often include instrumentation to measure pressure and temperature in order to control compressor performance.

[[Bernoulli's principle|Bernoulli's fluid dynamic principle]] plays an important role in understanding vaneless stationary components like an inlet. In engineering situations assuming [[Adiabatic process|adiabatic flow]], this equation can be written in the form:

Equation-1.1
:<math>\left(\left(\frac {v^2}{2}\right)+\left(\frac {\gamma}{\gamma-1}\right)\frac {p}{\rho}\right)_0 = \left(\left(\frac {v^2}{2}\right)+\left(\frac {\gamma}{\gamma-1}\right)\frac {p}{\rho}\right)_1</math>

where:
*{{mvar|0}} is the inlet of the compressor, station 0
*{{mvar|1}} is the inlet of the impeller, station 1
*{{mvar|p}} is the [[pressure]]
*{{mvar|ρ}} is the [[density]] and <math>\rho(\tilde{p})</math> indicates that it is a function of pressure
*<math>v</math> is the [[flow speed]]
*{{mvar|γ}} is the [[Heat capacity ratio|ratio of the specific heats]] of the fluid