Hydraulics

Pipe Headloss : Colebrook White

Pipe Headloss : Colebrook White Formula Formula The Darcy Weisbach Equation for calculating the pipe losses is as below; In the Darcy–Weisbach Equation, the friction factor f  can be calculated from the equation of Colebrook–White.  where k is the absolute roughness of the pipe wall (mm), D the inner diameter of the pipe (mm) and read more

Allowable Leakage

Allowable Leakage in Pipes Formula Allowable leakage during the maintenance stage of pipe carefully laid and well tested during construction is given by: Where, qL = Allowable Leakage in Cu.cm per hour, N = Number of Joints in length D = Diameter of pipe in mm, P = Average Test Pressure during leakage Test in read more

Ground Water Flow : Pressure Well

Ground Water Flow: Pressure Well Formula The Ground water flow in pressure well in equilibrium conditions is as follows: The discharge formula in pressure well is as given below; Where, Q = Discharge in cubic meter per day, k = Permeability meter/day, m = Depth of confined aquifer in meters, H = Depth of water read more

Discharge : Venturi Meter

Flow in closed conduits: Venturi Meter Formula The discharge through a venturi meter is as given below; Where, Q = Discharge in cubic meter per second, a1 = Area of pipe section in Sq meters, a2 = Area of throat section in Sq meters, h = head difference between inlet and throat section K = read more

Discharge : Drop

Open Channel Flow: Drop Formula In a drop, water falls freely from a channel to some lower level. Rough estimates of flow could be made by measuring the depth of flow at drop. The required conditions are as follows: The minimum straight upstream reach for approach channel shall be at least 20 times the end read more

Discharge : Rectangular Notch

Open Channel Flow: Rectangular Notch The minimum width of Notches shall be at least 150 mm. Rectangular notches are generally used for measuring small flows. Formula The discharge calculation formula from Rectangular notches is as given below; Where, Q = Discharge in cubic meter per second, be = Effective Width in meters, h = Effective read more

Discharge : V Notch

Open Channel Flow: V Notch The Notches are made from thin metal sheets. Triangular notches are generally used for measuring small flows upto about 1.25 m/s. Formula The discharge calculation formula from triangular notches is as given below; Where, Q = Discharge in cubic meter per second, Theta = Angle of Notch at center, h read more

Pipe Headloss – Modified Hazen William

Pipe Headloss : Modified Hazen-William Formula The Modified Hazen Williams formula is derived from Darcy Weisbach formula and is as below; Where, V = Velocity of flow, Cr = Coefficient of Roughness, d = Pipe Diameter/sec, g = Acceleration due to gravity, s = Hydraulic Gradient, v = Viscosity of Fluid For circular conduits, headloss read more

Mannings Equation

Mannings Equation

Mannings Equation The headloss through a conduit for gravity flow is calculated using Manning’s equation, as given below;     Coefficients for Mannings equation are as follows; Type of material Condition n Salt glazed stone ware pipe Good 0.012 Fair 0.015 Cement concrete pipes (with collar joints) Good 0.013 Fair 0.015 Spun concrete pipes (with read more