Time Required to Lower Liquid Surface 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%
✖The Coefficient of Discharge is ratio of actual discharge to theoretical discharge.ⓘ Coefficient of Discharge [C_d]			+10% -10%
✖The Acceleration due to Gravity is acceleration gained by an object because of gravitational force.ⓘ Acceleration due to Gravity [g]			+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%
✖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 is the time duration between two events/entities of interest.ⓘ Time Required to Lower Liquid Surface [Δt]

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Time Required to Lower Liquid Surface Solution

STEP 0: Pre-Calculation Summary

Formula Used

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))
Δt = ((2*A_R)/((2/3)*C_d*sqrt(2*g)*L_w))*(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 - (Measured in Second) - Time interval is the time duration between two events/entities of interest.
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.
Coefficient of Discharge - The Coefficient of Discharge is ratio of actual discharge to theoretical discharge.
Acceleration due to Gravity - (Measured in Meter per Square Second) - The Acceleration due to Gravity is acceleration gained by an object because of gravitational force.
Length of Weir Crest - (Measured in Meter) - Length of Weir Crest is the measurement or extent of Weir Crest from end to end.
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
Coefficient of Discharge: 0.66 --> No Conversion Required
Acceleration due to Gravity: 9.8 Meter per Square Second --> 9.8 Meter per Square Second No Conversion Required
Length of Weir Crest: 3 Meter --> 3 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

Δt = ((2*A_R)/((2/3)*C_d*sqrt(2*g)*L_w))*(1/sqrt(h₂)-1/sqrt(H_Upstream)) --> ((2*13)/((2/3)*0.66*sqrt(2*9.8)*3))*(1/sqrt(5.1)-1/sqrt(10.1))

Evaluating ... ...

Δt = 0.570146928531847

STEP 3: Convert Result to Output's Unit

0.570146928531847 Second --> No Conversion Required

FINAL ANSWER

0.570146928531847 ≈ 0.570147 Second <-- Time Interval

(Calculation completed in 00.004 seconds)

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Created by M Naveen

National Institute of Technology (NIT), Warangal

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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 Formula

LaTeX Go

What is meant by Coefficient of Discharge?

Coefficient of Discharge is the ratio of the actual discharge to the theoretical discharge, i.e., the ratio of the mass flow rate at the discharge end.

How to Calculate Time Required to Lower Liquid Surface?

Time Required to Lower Liquid Surface calculator uses 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)) to calculate the Time Interval, The Time Required to Lower Liquid Surface is defined as amount of time taken by lowering water surface from H1 to H2. Time Interval is denoted by Δt symbol.

How to calculate Time Required to Lower Liquid Surface using this online calculator? To use this online calculator for Time Required to Lower Liquid Surface, enter Cross-Sectional Area of Reservoir (A_R), Coefficient of Discharge (C_d), Acceleration due to Gravity (g), Length of Weir Crest (L_w), 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 calculation can be explained with given input values -> 0.570147 = ((2*13)/((2/3)*0.66*sqrt(2*9.8)*3))*(1/sqrt(5.1)-1/sqrt(10.1)).

FAQ

What is Time Required to Lower Liquid Surface?

The Time Required to Lower Liquid Surface is defined as amount of time taken by lowering water surface from H1 to H2 and is represented as Δt = ((2*A_R)/((2/3)*C_d*sqrt(2*g)*L_w))*(1/sqrt(h₂)-1/sqrt(H_Upstream)) or 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 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, The Coefficient of Discharge is ratio of actual discharge to theoretical discharge, The Acceleration due to Gravity is acceleration gained by an object because of gravitational force, Length of Weir Crest is the measurement or extent of Weir Crest from end to end, 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?

The Time Required to Lower Liquid Surface is defined as amount of time taken by lowering water surface from H1 to H2 is calculated using 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)). To calculate Time Required to Lower Liquid Surface, you need Cross-Sectional Area of Reservoir (A_R), Coefficient of Discharge (C_d), Acceleration due to Gravity (g), Length of Weir Crest (L_w), 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, Coefficient of Discharge, Acceleration due to Gravity, Length of Weir Crest, 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.

How many ways are there to calculate Time Interval?

In this formula, Time Interval uses Cross-Sectional Area of Reservoir, Coefficient of Discharge, Acceleration due to Gravity, Length of Weir Crest, Head on Downstream of Weir & Head on Upstream of Weir. We can use 2 other way(s) to calculate the same, which is/are as follows -

Time Interval = ((2*Cross-Sectional Area of Reservoir)/(Bazins Coefficient*sqrt(2*Acceleration due to Gravity)))*(1/sqrt(Head on Downstream of Weir)-1/sqrt(Head on Upstream of Weir))
Time Interval = (((2/3)*Cross-Sectional Area of Reservoir)/((8/15)*Coefficient of Discharge*sqrt(2*Acceleration due to Gravity)*tan(Theta/2)))*((1/Head on Downstream of Weir^(3/2))-(1/Head on Upstream of Weir^(3/2)))

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