Time Required to Lower Liquid Surface using Francis Formula Calculator

✖Cross-Sectional Area of Reservoir is the area of a reservoir that is obtained when a three-dimensional reservoir shape is sliced perpendicular to some specified axis at a point.ⓘ Cross-Sectional Area of Reservoir [A_R]			+10% -10%
✖Length of Weir Crest is the measurement or extent of Weir Crest from end to end.ⓘ Length of Weir Crest [L_w]			+10% -10%
✖Number of End Contraction 1 can be described as the end contractions acting on a channel.ⓘ Number of End Contraction [n]			+10% -10%
✖Average Height of Downstream and Upstream is the height of downstream and upstream.ⓘ Average Height of Downstream and Upstream [H_Avg]			+10% -10%
✖Head on Downstream of Weir pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures.ⓘ Head on Downstream of Weir [h₂]			+10% -10%
✖Head on Upstream of Weirr pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures.ⓘ Head on Upstream of Weir [H_Upstream]			+10% -10%

✖Time Interval for Francis is calculated with the help of francis formula.ⓘ Time Required to Lower Liquid Surface using Francis Formula [t_F]

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Time Required to Lower Liquid Surface using Francis Formula Solution

STEP 0: Pre-Calculation Summary

Formula Used

Time Interval for Francis = ((2*Cross-Sectional Area of Reservoir)/(1.84*(Length of Weir Crest-(0.1*Number of End Contraction*Average Height of Downstream and Upstream))))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir))
t_F = ((2*A_R)/(1.84*(L_w-(0.1*n*H_Avg))))*(1/sqrt(h₂)-1/sqrt(H_Upstream))
This formula uses 1 Functions, 7 Variables

Functions Used

sqrt - A square root function is a function that takes a non-negative number as an input and returns the square root of the given input number., sqrt(Number)

Variables Used

Time Interval for Francis - (Measured in Second) - Time Interval for Francis is calculated with the help of francis formula.
Cross-Sectional Area of Reservoir - (Measured in Square Meter) - Cross-Sectional Area of Reservoir is the area of a reservoir that is obtained when a three-dimensional reservoir shape is sliced perpendicular to some specified axis at a point.
Length of Weir Crest - (Measured in Meter) - Length of Weir Crest is the measurement or extent of Weir Crest from end to end.
Number of End Contraction - Number of End Contraction 1 can be described as the end contractions acting on a channel.
Average Height of Downstream and Upstream - (Measured in Meter) - Average Height of Downstream and Upstream is the height of downstream and upstream.
Head on Downstream of Weir - (Measured in Meter) - Head on Downstream of Weir pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures.
Head on Upstream of Weir - (Measured in Meter) - Head on Upstream of Weirr pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures.

STEP 1: Convert Input(s) to Base Unit

Cross-Sectional Area of Reservoir: 13 Square Meter --> 13 Square Meter No Conversion Required
Length of Weir Crest: 3 Meter --> 3 Meter No Conversion Required
Number of End Contraction: 4 --> No Conversion Required
Average Height of Downstream and Upstream: 5.5 Meter --> 5.5 Meter No Conversion Required
Head on Downstream of Weir: 5.1 Meter --> 5.1 Meter No Conversion Required
Head on Upstream of Weir: 10.1 Meter --> 10.1 Meter No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

t_F = ((2*A_R)/(1.84*(L_w-(0.1*n*H_Avg))))*(1/sqrt(h₂)-1/sqrt(H_Upstream)) --> ((2*13)/(1.84*(3-(0.1*4*5.5))))*(1/sqrt(5.1)-1/sqrt(10.1))

Evaluating ... ...

t_F = 2.26350233027382

STEP 3: Convert Result to Output's Unit

2.26350233027382 Second --> No Conversion Required

FINAL ANSWER

2.26350233027382 ≈ 2.263502 Second <-- Time Interval for Francis

(Calculation completed in 00.004 seconds)

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Created by M Naveen

National Institute of Technology (NIT), Warangal

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National Institute of Technology Karnataka (NITK), Surathkal

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< Time Required to Empty a Reservoir with Rectangular Weir Calculators

Coefficient of Discharge for Time Required to Lower Liquid Surface

LaTeX Go Coefficient of Discharge = ((2*Cross-Sectional Area of Reservoir)/((2/3)*Time Interval*sqrt(2*Acceleration due to Gravity)*Length of Weir Crest))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir))

Length of Crest for time required to Lower Liquid Surface

LaTeX Go Length of Weir Crest = ((2*Cross-Sectional Area of Reservoir)/((2/3)*Coefficient of Discharge*sqrt(2*Acceleration due to Gravity)*Time Interval))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir))

Time Required to Lower Liquid Surface

LaTeX Go Time Interval = ((2*Cross-Sectional Area of Reservoir)/((2/3)*Coefficient of Discharge*sqrt(2*Acceleration due to Gravity)*Length of Weir Crest))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir))

Cross Sectional Area given Time required to Lower Liquid Surface

LaTeX Go Cross-Sectional Area of Reservoir = (Time Interval*(2/3)*Coefficient of Discharge*sqrt(2*Acceleration due to Gravity)*Length of Weir Crest)/(2*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir)))

Time Required to Lower Liquid Surface using Francis Formula Formula

LaTeX Go

What is meant by Head?

Hydraulic head is a specific measurement of liquid pressure above a vertical datum. It is usually measured as a liquid surface elevation.

How to Calculate Time Required to Lower Liquid Surface using Francis Formula?

Time Required to Lower Liquid Surface using Francis Formula calculator uses Time Interval for Francis = ((2*Cross-Sectional Area of Reservoir)/(1.84*(Length of Weir Crest-(0.1*Number of End Contraction*Average Height of Downstream and Upstream))))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir)) to calculate the Time Interval for Francis, The Time Required to Lower Liquid Surface using Francis Formula as amount of time taken by lowering water surface from Head1 to Head2. Time Interval for Francis is denoted by t_F symbol.

How to calculate Time Required to Lower Liquid Surface using Francis Formula using this online calculator? To use this online calculator for Time Required to Lower Liquid Surface using Francis Formula, enter Cross-Sectional Area of Reservoir (A_R), Length of Weir Crest (L_w), Number of End Contraction (n), Average Height of Downstream and Upstream (H_Avg), Head on Downstream of Weir (h₂) & Head on Upstream of Weir (H_Upstream) and hit the calculate button. Here is how the Time Required to Lower Liquid Surface using Francis Formula calculation can be explained with given input values -> 2.263502 = ((2*13)/(1.84*(3-(0.1*4*5.5))))*(1/sqrt(5.1)-1/sqrt(10.1)).

FAQ

What is Time Required to Lower Liquid Surface using Francis Formula?

The Time Required to Lower Liquid Surface using Francis Formula as amount of time taken by lowering water surface from Head1 to Head2 and is represented as t_F = ((2*A_R)/(1.84*(L_w-(0.1*n*H_Avg))))*(1/sqrt(h₂)-1/sqrt(H_Upstream)) or Time Interval for Francis = ((2*Cross-Sectional Area of Reservoir)/(1.84*(Length of Weir Crest-(0.1*Number of End Contraction*Average Height of Downstream and Upstream))))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir)). Cross-Sectional Area of Reservoir is the area of a reservoir that is obtained when a three-dimensional reservoir shape is sliced perpendicular to some specified axis at a point, Length of Weir Crest is the measurement or extent of Weir Crest from end to end, Number of End Contraction 1 can be described as the end contractions acting on a channel, Average Height of Downstream and Upstream is the height of downstream and upstream, Head on Downstream of Weir pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures & Head on Upstream of Weirr pertains to the energy status of water in water flow systems and is useful for describing flow in hydraulic structures.

How to calculate Time Required to Lower Liquid Surface using Francis Formula?

The Time Required to Lower Liquid Surface using Francis Formula as amount of time taken by lowering water surface from Head1 to Head2 is calculated using Time Interval for Francis = ((2*Cross-Sectional Area of Reservoir)/(1.84*(Length of Weir Crest-(0.1*Number of End Contraction*Average Height of Downstream and Upstream))))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir)). To calculate Time Required to Lower Liquid Surface using Francis Formula, you need Cross-Sectional Area of Reservoir (A_R), Length of Weir Crest (L_w), Number of End Contraction (n), Average Height of Downstream and Upstream (H_Avg), Head on Downstream of Weir (h₂) & Head on Upstream of Weir (H_Upstream). With our tool, you need to enter the respective value for Cross-Sectional Area of Reservoir, Length of Weir Crest, Number of End Contraction, Average Height of Downstream and Upstream, Head on Downstream of Weir & Head on Upstream of Weir and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

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