Multistage Blowers Terminology

Axial

Axial (as in axial fan)means it's located on, around, or in the center, or axis.

Centrifugal

Centrifugal (centrifugal pump for example) means moving or directed away from a center or axis.

CFM

Cubic feet per minute (CFPM or CFM) is a non-SI unit of measurement of the flow of a gas or liquid that indicates how much volume in cubic feet pass by a stationary point in one minute. The higher the CFPM the better the suction.

Computational  Fluid  Dynamics

The prediction of the behaviour of fluids and of the effects of fluid motion past objects by numerical methods rather than model experiments

Finite Element Analysis

The finite element method (FEM) (sometimes referred to as finite element analysis (FEA)) is a numerical technique for finding approximate solutions of partial differential equations (PDE) as well as of integral equations. The solution approach is based either on eliminating the differential equation completely (steady state problems), or rendering the PDE into an approximating system of ordinary differential equations, which are then numerically integrated using standard techniques such as Euler's method, Runge-Kutta, etc.

Psi / Psig

The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/in2 or lbf/in2) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch:
1 psi (6.894757 kPa) : pascal (Pa) is the SI unit of pressure.

Tensile

Capable of being stretched or extended.

WG Pressure

The letters wg stands for inch water gauge, another name for an inch of water.The gauge measures the difference between the pressure in the pipe and the pressure of the atmosphere.