Height of Liquid Crest over Weir Calculator

✖Liquid Mass Flowrate is the mass flow rate of the liquid component in the column.ⓘ Liquid Mass Flowrate [L_w]			+10% -10%
✖The weir length refers to the length of support strips which plays a significant role in controlling liquid distribution, within the column.ⓘ Weir Length [l_w]			+10% -10%
✖Liquid Density is defined as the ratio of mass of given fluid with respect to the volume that it occupies.ⓘ Liquid Density [ρ_L]			+10% -10%

✖Weir Crest is designed to have a specific height for the liquid flow across the tray.ⓘ Height of Liquid Crest over Weir [h_ow]

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Formula

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Height of Liquid Crest over Weir

Formula

`"h"_{"ow"} = (750/1000)*(("L"_{"w"}/("l"_{"w"}*"ρ"_{"L"}))^(2/3))`

Example

`"0.022711m"=(750/1000)*(("12.856kg/s"/("2.452m"*"995kg/m³"))^(2/3))`

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Height of Liquid Crest over Weir Solution

STEP 0: Pre-Calculation Summary

Formula Used

Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3))
h_ow = (750/1000)*((L_w/(l_w*ρ_L))^(2/3))
This formula uses 4 Variables

Variables Used

Weir Crest - (Measured in Meter) - Weir Crest is designed to have a specific height for the liquid flow across the tray.
Liquid Mass Flowrate - (Measured in Kilogram per Second) - Liquid Mass Flowrate is the mass flow rate of the liquid component in the column.
Weir Length - (Measured in Meter) - The weir length refers to the length of support strips which plays a significant role in controlling liquid distribution, within the column.
Liquid Density - (Measured in Kilogram per Cubic Meter) - Liquid Density is defined as the ratio of mass of given fluid with respect to the volume that it occupies.

STEP 1: Convert Input(s) to Base Unit

Liquid Mass Flowrate: 12.856 Kilogram per Second --> 12.856 Kilogram per Second No Conversion Required
Weir Length: 2.452 Meter --> 2.452 Meter No Conversion Required
Liquid Density: 995 Kilogram per Cubic Meter --> 995 Kilogram per Cubic Meter No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

h_ow = (750/1000)*((L_w/(l_w*ρ_L))^(2/3)) --> (750/1000)*((12.856/(2.452*995))^(2/3))

Evaluating ... ...

h_ow = 0.0227109939449152

STEP 3: Convert Result to Output's Unit

0.0227109939449152 Meter --> No Conversion Required

FINAL ANSWER

0.0227109939449152 ≈ 0.022711 Meter <-- Weir Crest

(Calculation completed in 00.004 seconds)

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Created by Rishi Vadodaria

Malviya National Institute Of Technology (MNIT JAIPUR ), JAIPUR

Rishi Vadodaria has created this Calculator and 200+ more calculators!

Verified by Vaibhav Mishra

DJ Sanghvi College of Engineering (DJSCE), Mumbai

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< 25 Distillation Tower Design Calculators

Relative Volatility of Two Components Based on Normal Boiling Point and Latent Heat of Vaporization

Go Relative Volatility = exp(0.25164*((1/Normal Boiling Point of Component 1)-(1/Normal Boiling Point of Component 2))*(Latent Heat of Vaporization of Component 1+Latent Heat of Vaporization of Component 2))

Maximum Allowable Vapor Velocity given Plate Spacing and Fluid Densities

Go Maximum Allowable Vapor Velocity = (-0.171*(Plate Spacing)^2+0.27*Plate Spacing-0.047)*((Liquid Density-Vapor Density in Distillation)/Vapor Density in Distillation)^0.5

Column Diameter given Maximum Vapor Rate and Maximum Vapor Velocity

Go Column Diameter = sqrt((4*Vapor Mass Flowrate)/(pi*Vapor Density in Distillation*Maximum Allowable Vapor Velocity))

Tower Cross Sectional Area given Gas Volumetric Flow and Flooding Velocity

Go Tower Cross Sectional Area = Volumetric Gas Flow/((Fractional Approach to Flooding Velocity*Flooding Velocity)*(1-Fractional Downcomer Area))

Minimum External Reflux given Compositions

Go External Reflux Ratio = (Distillate Composition-Equilibrium Vapor Composition)/(Equilibrium Vapor Composition-Equilibrium Liquid Composition)

Maximum Allowable Mass Velocity using Bubble Cap Trays

Go Maximum Allowable Mass Velocity = Entrainment Factor*(Vapor Density in Distillation*(Liquid Density-Vapor Density in Distillation)^(1/2))

Minimum Internal Reflux given Compositions

Go Internal Reflux Ratio = (Distillate Composition-Equilibrium Vapor Composition)/(Distillate Composition-Equilibrium Liquid Composition)

Dry Plate Pressure Drop in Distillation Column Design

Go Dry Plate Head Loss = 51*((Vapor Velocity Based on Hole Area/Orifice Coefficient)^2)*(Vapor Density in Distillation/Liquid Density)

Flooding Velocity in Distillation Column Design

Go Flooding Velocity = Capacity Factor*((Liquid Density-Vapor Density in Distillation)/Vapor Density in Distillation)^0.5

Weep Point Velocity in Distillation Column Design

Go Weep Point Vapor Velocity Based on Hole Area = (Weep Point Correlation Constant-0.90*(25.4-Hole Diameter))/((Vapor Density in Distillation)^0.5)

Liquid Vapor Flow Factor in Distillation Column Design

Go Flow Factor = (Liquid Mass Flowrate/Vapor Mass Flowrate)*((Vapor Density in Distillation/Liquid Density)^0.5)

Downcomer Residence Time in Distillation Column

Go Residence Time = (Downcomer Area*Clear Liquid Backup*Liquid Density)/Liquid Mass Flowrate

Internal Reflux Ratio Based on Liquid and Distillate Flowrates

Go Internal Reflux Ratio = Liquid Reflux Flowrate/(Liquid Reflux Flowrate+Distillate Flowrate)

Column Diameter Based on Vapor Flowrate and Mass Velocity of Vapor

Go Column Diameter = ((4*Vapor Mass Flowrate)/(pi*Maximum Allowable Mass Velocity))^(1/2)

Head Loss in Downcomer of Tray Tower

Go Downcomer Headloss = 166*((Liquid Mass Flowrate/(Liquid Density*Downcomer Area)))^2

Height of Liquid Crest over Weir

Go Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3))

Active Area given Gas Volumetric Flow and Flow Velocity

Go Active Area = Volumetric Gas Flow/(Fractional Downcomer Area*Flooding Velocity)

Fractional Downcomer Area given Total Cross Sectional Area

Go Fractional Downcomer Area = 2*(Downcomer Area/Tower Cross Sectional Area)

Fractional Active Area given Downcomer Area and Total Column Area

Go Fractional Active Area = 1-2*(Downcomer Area/Tower Cross Sectional Area)

Internal Reflux Ratio Given External Reflux Ratio

Go Internal Reflux Ratio = External Reflux Ratio/(External Reflux Ratio+1)

Tower Cross Sectional Area given Fractional Active Area

Go Tower Cross Sectional Area = Active Area/(1-Fractional Downcomer Area)

Tower Cross Sectional Area given Active Area

Go Tower Cross Sectional Area = Active Area/(1-Fractional Downcomer Area)

Clearance Area under Downcomer given Weir Length and Apron Height

Go Clearance Area Under Downcomer = Apron Height*Weir Length

Fractional Active Area given Fractional Downcomer Area

Go Fractional Active Area = 1-Fractional Downcomer Area

Residual Head Loss in Pressure in Distillation Column

Go Residual Head Loss = (12.5*10^3)/Liquid Density

Height of Liquid Crest over Weir Formula

Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3))
h_ow = (750/1000)*((L_w/(l_w*ρ_L))^(2/3))

What is the Role of Weir Crest?

The weir crest plays a critical role in ensuring even liquid distribution across the tray. By controlling the height of the weir crest, engineers can maintain a consistent liquid depth on the tray surface. This promotes effective mass transfer and separation by allowing the liquid to flow evenly over the tray area and come into contact with the rising vapor.

What is Weir Length?

The weir length plays a significant role in controlling liquid distribution, maintaining the liquid level, and ensuring effective separation within the column. The design of the weir length is crucial for achieving the desired distillation performance.

How to Calculate Height of Liquid Crest over Weir?

Height of Liquid Crest over Weir calculator uses Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3)) to calculate the Weir Crest, The Height of Liquid Crest over Weir formula is defined as the boundary for the liquid flow across the tray. It plays a crucial role in controlling the flow of liquid on the tray. Weir Crest is denoted by h_ow symbol.

How to calculate Height of Liquid Crest over Weir using this online calculator? To use this online calculator for Height of Liquid Crest over Weir, enter Liquid Mass Flowrate (L_w), Weir Length (l_w) & Liquid Density (ρ_L) and hit the calculate button. Here is how the Height of Liquid Crest over Weir calculation can be explained with given input values -> 0.022711 = (750/1000)*((12.856/(2.452*995))^(2/3)).

FAQ

What is Height of Liquid Crest over Weir?

The Height of Liquid Crest over Weir formula is defined as the boundary for the liquid flow across the tray. It plays a crucial role in controlling the flow of liquid on the tray and is represented as h_ow = (750/1000)*((L_w/(l_w*ρ_L))^(2/3)) or Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3)). Liquid Mass Flowrate is the mass flow rate of the liquid component in the column, The weir length refers to the length of support strips which plays a significant role in controlling liquid distribution, within the column & Liquid Density is defined as the ratio of mass of given fluid with respect to the volume that it occupies.

How to calculate Height of Liquid Crest over Weir?

The Height of Liquid Crest over Weir formula is defined as the boundary for the liquid flow across the tray. It plays a crucial role in controlling the flow of liquid on the tray is calculated using Weir Crest = (750/1000)*((Liquid Mass Flowrate/(Weir Length*Liquid Density))^(2/3)). To calculate Height of Liquid Crest over Weir, you need Liquid Mass Flowrate (L_w), Weir Length (l_w) & Liquid Density (ρ_L). With our tool, you need to enter the respective value for Liquid Mass Flowrate, Weir Length & Liquid Density 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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