FLOW COEFFICIENT, HEAD OR WORK COEFFICIENT, DEFLECTION COEFFICIENT, AND PRESSURE CO-EFFICIENT

Flow Coefficient: It is defined as the ratio of flow (or axial) velocity at inlet to the blade velocity. Mathematically, we can write

Flow coefficient, 

Now u = v_f1 (tan α₁ + tan β₁)

Also, v_f1 = v_f2 = v_f

Head or Work Coefficient: It is defined as the ratio of actual work done to the kinetic energy corresponding to the mean peripheral velocity. One can write

Head or work coefficient,

Deflection Coefficient: ϕ_def: It is defined as,

Pressure coefficient: It is defined as the ratio of isentropic work done to kinetic energy corresponding to the peripheral velocity.