Sage-Tips

What is the general value for coefficient of contraction?

Explanation: the ratio of the area of a jet at vena contracta to the area of orifice is known as the coefficient of contraction. the value of cc varies from 0.61 to 0.69 for different orifices.

What is coefficient of contraction fluid mechanics?

The coefficient of contraction is defined as the ratio between the area of the jet at the vena contracta and the area of the orifice. Cc = Area at vena contracta/Area of orifice. The typical value may be taken as 0.611 for a sharp orifice (concentric with the flow channel).

Can the coefficient of contraction be greater than 1?

In practice, the discharge coefficient cannot be greater than one. This is a fact. The error may be in compensating the values ​​of the variables in the equation. Verifies units, values, and homogeneity of area values.

What is Borda’s mouthpiece?

Borda’s mouthpiece is a short cylindrical tube projecting inward. The edge of the tube must be relatively thin and sharp to ensure perfect contraction, and its length, about ½ diameter, such that the jet will not touch the sides of the tube.

Why is coefficient of contraction important?

The coefficient of contraction Cc is an important parameter for accurate discharge measurement in open channels. The Cc and Cv values under free and submerged flow conditions are obtained from the measured jet velocity and the discharge.

What is the theoretical value of coefficient of contraction for the sharp edged orifice?

for sharp edged orifices the value of Cv is 0.98.

How is the velocity coefficient Cv the discharge coefficient Cd and the contraction coefficient CC?

Coefficient of discharge (Cd) = Coeff. of flow/velocity (Cv) x Coeff of contraction (Cc). of flow/velocity (Cv) , you will be able to calculate coeff of discharge (Cd), once Cc is known. Obviously Cc changes depending on the shape of the jet at vena contract however a value between 0.61 – 0.64 is usually accepted.

Can the loss coefficient be greater than 1?

The coefficient can range in value between 0 and 1. Larger head loss coefficients are associated with increased flow contraction in the inlet zone.

Which mouthpiece has maximum coefficient of discharge?

Convergent-Divergent mouthpiece
Therefore, the Convergent-Divergent mouthpiece is having maximum discharge.

What is convergent-divergent mouthpiece?

Overview. In this type of mouthpiece, the mouthpiece is first made convergent up to the vena contracta of the jet and beyond that it is made divergent. Such a mouthpiece, which is first convergent is known as convergent-divergent mouthpiece as shown in figure.

Will the value of CV be different for sharp edged and rounded orifices Why?

It is defined as the ratio of the actual velocity of the jet at veena contracta V to the theoretical velocity Vth. Generally the value of Cv varies from 0.95 to . 99 for different orifices depending upon their size, shape, head etc. for sharp edged orifices the value of Cv is 0.98.

What is the coefficient of contraction in an internal mouthpiece?

Previously we have seen that the coefficient of contraction in an internal mouthpiece is 0.5. Therefore substituting the value of = 0.5 in the above equation, (5) We see that the jet after passing through section 1-1 suddenly enlarges at section 2-2.

What is re-entrantor Borda’s mouthpiece?

An internal mouthpiece, extending into the fluid (i.e., inside the vessel) is known as Re-entrantor Borda’smouthpiece. There are mainly two types of internal mouthpieces depending upon their nature of discharge: Mouthpiece running free

What are the different types of internal mouthpieces?

There are mainly two types of internal mouthpieces depending upon their nature of discharge: Mouthpiece running free Mouthpiece running full In this page we will discuss about the discharge and pressure in an internal mouthpiece when it runs free and full. Discharge Through An Internal Mouthpiece

What is the meaning of coefficient of contraction (cc)?

Coefficient of Contraction (Cc) 1 Coefficient of Contraction (Cc) It is the ratio of area of water jet at vena-contracta to the area of the orifice. 2 Coefficient of Velocity (Cv) It is the ratio of velocity of water jet at vena-contracta to the theoretical velocity. 3 Coefficient of discharge (Cd)