What are the units for the weir coefficient?
The weir coefficient, since it is a function of the gravitational constant, is not dimensionless and therefore has different values depending on which unit system you are using. For example, a weir coefficient (C) of 3.00 in English Units would be 1.66 in SI units.
What is the weir equation?
The Weir formula is a formula used in indirect calorimetry, relating metabolic rate to oxygen consumption and carbon dioxide production. According to original source, it says: Metabolic rate (kcal per day) = 1440 (3.94 VO2 + 1.11 VCO2)
How do you measure flow in a weir?
Weirs to Measure Flow It works by raising the water level upstream of the weir, and then forcing the water to spill over. The more water is flowing over the weir, the deeper the water will be upstream of the weir. So measuring flow rate (CFS) can be done by simply measuring the depth of the water upstream.
What is Francis formula?
[′fran·səs ‚fȯr·myə·lə] (fluid mechanics) An equation for the calculation of water flow rate over a rectangular weir in terms of length and head.
How is weir coefficient calculated?
The equation recommended by the Bureau of Reclamation in their Water Measurement Manual, for use with a suppressed rectangular weir is: Q = 3.33 B H3/2, where Q is the water flow rate in ft3/sec, B is the length of the weir (and the channel width) in ft, and H is the head over the weir in ft.
How is weir height calculated?
The Length is the bottom width of the weir. The height is measured from the bottom of the weir opening to the top of the water level ponded behind the weir (not the water level right as it leaves the weir).
What is a weir notch?
A notch is generally meant to measure the flow of water from a tank. A weir is also a notch but it is made on a large scale. The weir is a notch cut in a dam to discharge the surplus quantity of water. Water flows over a notch or weir while water passes through an orifice.
How do you calculate flow through AV notch weir?
The Equation
- The equation to determine the flow rate of a 90° Triangular Notch Weir is:
- = Flow Rate in cfs.
- = Height of the upstream water above the bottom of the weir in feet.
What is Francis formula for rectangular weir?
| Q. | According to Francis formula, the discharge over a rectangular weir is (where n = Number of end contractions) |
|---|---|
| A. | (2/3) × Cd (L – nH) × |
| B. | (2/3) × Cd (L – 0.1nH) × × H3/2 |
| C. | (2/3) × Cd (L – nH) × × H² |
| D. | (2/3) × Cd (L – nH) × × H5/2 |
What is a standard weir?
Standard Contracted Rectangular Weirs. The fully contracted rectangular weir (figure 7-1) is the most frequent standard weir used in irrigation. To be fully contracted, all overflow plate sides and ends must be located at least a distance of 2h1max (two maximum measurement heads) from the approach flow boundaries.
What is weir discharge coefficient?
The flat-topped low weirs generally include broad-crested weir and short-crested weir. Under the same inflow condition, the discharge coefficient of short-crested weir is approximately 0.33–0.46, while that of broad-crested weir is 0.32–0.385, hence the former is stronger than the latter in terms of discharge capacity.
How is weir overflow rate calculated?
The overflow rate (also known as the surface loading or the surface overflow rate) is equal to the settling velocity of the smallest particle which the basin will remove. Surface loading is calculated by dividing the flow by the surface area of the tank. Overflow rate should usually be less than 1,000 gal/day-ft.
What is the Weir formula used for?
The Weir formula is a formula used in indirect calorimetry, relating metabolic rate to oxygen consumption and carbon dioxide production. According to original source, it says: where VO 2 is oxygen consumption in litres per minute and VCO 2 is the rate of carbon dioxide production in litres per minute.
What is the Francis formula for flow through a weir?
The Francis Formula – Imperial Units. Flow through a rectangular weir can be expressed in imperial units with the Francis formula. q = 3.33 (b – 0.2 h) h3/2 (1b) where. q = flow rate (ft3/s) h = head on the weir (ft) b = width of the weir (ft) Alternative with height in inches and flow in gpm:
How do you calculate the unit of a rectangular weir?
Units in rectangular weir calculation: cm=centimeter, ft=foot, gal=US gallon, m=meter, min=minute, s=second. Rectangular weir topics: Introduction Equations Installation Guidelines and Equation Applicability Error Messages References Introduction The rectangular weir is the most commonly used thin plate weir.
What is the Kindsvater-Carter rectangular weir equation?
Rectangular Weir Equation The Kindsvater-Carter rectangular weir equation (ISO, 1980): The sum b+K b is called “effective width” and the sum h+K h is called “effective head.”. The value for g is 9.8066 m/s 2 and K h =0.001 m. C e is a function of b/B and h/P,…