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Ali Hamza
Ali Hamza
03 Feb 2019

How experimental determination of Hydraulic Coefficient is done??

Experimental Determination of HydraulicCoefficients

Co-efficient of Discharge (Cd)

β€’ The water is allowed to flow through an orifice fittedto a tank under a constant head at H.

β€’ The water is collected in a measuring tank for thetime t.

β€’ The height of water in the measuring tank isobserved and noted.

Qact =Β π΄π‘Ÿπ‘’π‘Ž π‘œπ‘“ π‘‘π‘Žπ‘›π‘˜ βˆ— π»π‘’π‘–π‘”β„Žπ‘‘ π‘œπ‘“ π‘€π‘Žπ‘‘π‘’π‘Ÿ 𝑖𝑛 π‘‘β„Žπ‘’ π‘‘π‘Žπ‘›π‘˜π‘‘π‘–π‘šπ‘’ π‘œπ‘“ π‘π‘œπ‘™π‘™π‘’π‘π‘‘π‘–π‘œπ‘›

Cd = π‘„π‘Žπ‘π‘‘π‘„π‘‘β„Ž=π‘„π‘Žπ‘π‘‘π΄π‘Ÿπ‘’π‘Ž π‘œπ‘“ π‘œπ‘Ÿπ‘–π‘“π‘–π‘π‘’ βˆ— 2𝑔𝐻

β€’ Suppose C-C represents the vena contracta of the jet of water coming out of the orifice under constant head H.Β 

β€’ Consider a liquid particle is at C-C when time t=0 and it takes the position P along the jet.Β 

Vertical distance = y = Β½ gt2 (t=x/V)

y= Β½ g (x2/V2 ) β‡’ V = 𝑔π‘₯2Β 2 𝑦 VthΒ = 2𝑔𝐻