The importance of the Hydraulic Coefficient is the three types of coefficients in fluid mechanics used to the coefficient of Contraction, coefficient of velocity, and coefficient of discharge, the relation between Cd.
Coefficient of Contraction
The ratio of the area of ​​the jet to the area of ​​the orifice on the vena contracta is called the coefficient of contraction and is denoted by Ce.
Ce = ac/aÂ
Ce = jet contraction area of ​​jet/area of ​​the orificeÂ
The average value of Ce for small and sharp-edged orifices is near about 0.64.
Coefficient of Velocity
The ratio of the actual velocity of the fluid at the vena contracta to the theoretical velocity of the fluid is called the velocity coefficient. It is denoted by Cv.
Cv = jet contracts per fluid velocity/theoretical velocity
Cv = Vc/√2gh
The average value of Cv is near about 0.97.Â
Coefficient of Discharge
Because the actual area and actual velocity of the jet are less than its theoretical values. The actual immersion will also be less than the theoretical immersion.
That is, the ratio of actual immersion and theoretical immersion is called the immersion coefficient, it is denoted by Cd.
Cd = Q/a√2gh
The value of Cd ranges from 0.61 to 0.621.Â
Relation between Cd (coefficient discharge)
If Q is the actual discharge under the influence of h head from the area orifice of A.
Cd = Q/a√2gh
Actual immersion=Actual velocity x Actual area
Cd = a x Ce x Cv x √2gh
Cd = a x Ce x Cv x √2gh/a√2ghÂ
Cd = Ce x CvÂ
Relation between Cd formulaÂ
