The section areas can be calculated like
a1 = (1 m) ((4 m) - (0 m)) / 2
= 2 m2
a2 = (1.5 m) ((6 m) - (2 m)) / 2
= 3 m2
a3 = (0.9 m) ((8 m) - (4 m)) / 2
= 1.8 m2
The flow rates can be calculated as
q1 = (3 m/s) (2 m2)
= 6 m3/s
q2 = (4 m/s) (3 m2)
= 12 m3/s
q3 = (3 m/s) (1.8 m2)
= 5.4 m3/s
The total flow can be summarized as
Q = (6 m3/s) + (12 m3/s) + (5.4 m3/s)
= 23.4 m3/s
Note - there are alternative ways to calculate the section flow rates:
Using the simple average of two successive vertical depths, their mean velocity, and the distance between them can be expressed as
qn to n+1 = [(vn + vn+1) / 2] [(dn + dn+1 ) / 2] (ln+1 - ln) (4)
With the midsection method, the depth and mean velocity are measured for each number of verticals along the cross section. The depth at a vertical is multiplied by the width, which extends halfway to the preceding vertical and halfway to the following vertical, to develop a cross-sectional area. The section flow rate can be expressed as
qn = vn [((ln - ln-1) + (ln+1 - ln)) / 2] dn (5)
Flow metering principles - Orifice, Venturi, Flow Nozzles, Pitot Tubes, Target, Variable Area, Positive Displacement, Turbine, Vortex, Electromagnetic, Ultrasonic Doppler, Ultrasonic Time-of-travel, Mass Coriolis, Mass Thermal, Weir V-notch, Flume Parshall and Sluice Gate flow meters and more.
A limited comparison of flowmeter principles - regarding service, rangeability, pressure loss, typical accuracy, upstream pipe diameters, viscosity and relative costs.
Introduction to accuracy in flow measurement devices.
Turndown ratio (Rangeability) can be used to compare flow measurement devices like orifices, venturi meters etc.
An introduction to the different types of fluid flowmeters - Orifices, Venturies, Nozzles, Rotameters, Pitot Tubes, Calorimetrics, Turbine, Vortex, Electromagnetic, Doppler, Ultrasonic, Thermal, Coriolis.
Depth and hydrostatic pressure.
Weirs can be used to measure flow rates in open channels and rivers - common for water supply and sewage plants.
The orifice, nozzle and venturi flow rate meters makes the use of the Bernoulli Equation to calculate fluid flow rate using pressure difference through obstructions in the flow.
Sluice gates can be used to control and measure volume flow rates in open channels and rivers, mainly in connection to hydro power plants.
Inclined and vertical u-tube manometers used to measure differential pressure in flow meters like pitot tubes, orifices and nozzles.
Dynamic pressure or velocity head.
Convert between volume flow units like gpm, liter/sec, cfm, m3/h.
A manual providing guidance in selecting, managing, inspecting, and maintaining water measurement devices - describes standard methods and devices commonly used to measure irrigation water.
Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!
We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.
Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.