Chapter:

Basics-Of-Open-Channel-Flow

1.

 An oil of viscosity 9 poise and specific gravity 0.9 is flowing through a horizontal pipe of 60 mm diameter. If pressure drop in 100 m length of pipe is `1800 (kN)/m^2`, determine:

  • The rate of flow of oil
  • The centre line velocity
  •  The total frictional drag over 100 m length
  • The power required to maintain flow
  • The velocity gradient at pipe wall
  • The velocity and shear stress at pipe wall
  • The velocity and shear stress at 8mm from wall.


2.

Oil of absolute viscosity 1.5 poise and density 848.3 kg/m3 flows through a ` 30` cm I.D. pipe. If head loss in `3000` m length of pipe is `20` m, assuming a laminar flow, determine :

  1. velocity, 
  2. Reynolds number and 
  3. friction factor (Fanning??s).

3. A crude oil of viscosity `0.9` poise and relative density `0.9` is flowing through a horizontal circular pipe of diameter `120` mm and length `12` m. Calculate difference of pressure at two ends of pipe, if `785 N` of oil is collected in a tank in` 25` seconds.

4. A liquid with a specific gravity `2.8` and a viscosity `0.8` poise flows through a smooth pipe of unknown diameter, resulting in a pressure drop of `800 N/m^2` in `2` km length of pipe. What is pipe diameter if mass flow rate is` 2500 (kg)/h`.

5.

A fluid of viscosity `8 `poise and specific gravity `1.2` is flowing through a circular pipe of diameter ` 100 `mm. The maximum shear stress at pipe wall is `210 N/m^2`. Find:

  1.  The pressure gradient,
  2.  The average velocity, and
  3. Reynolds number of flow.

6. A fluid of density `1200 (kg)/m^3` and viscosity `0.5 `poise is flowing at a rate of `5m^3/( min)` in a circular pipe of cross-section of `1 m^2`. Is flow laminar or turbulent? Can you predict maximum velocity of fluid in pipe ?

7.

A lubricating oil of viscosity 1 poise and specific gravity 0.9 is pumped through 

a 30 mm diameter pipe. If pressure drop per metre length of pipe is `20( kN)/m^2`, determine:

  1. The mass flow rate in kg/min,
  2.  The shear stress at pipe wall,
  3.  The Reynolds number of flow, and 
  4. The power required per 50 m length of pipe to maintain flow.

8.

In a pipe of 300 mm diameter, maximum velocity of flow is found to be 2 m/s. If flow is laminar,find:

  • average velocity and radius at which it occurs
  • velocity at 50mm from wall of pipe


9.

An oil of viscosity `0.15 (Ns)/m^2` and specific gravity 0.9 is flowing through a circular pipe of diameter 30 mm and of length 3 m at `1/10` th of critical velocity for which Reynolds number is 2450. Find:

  1. The velocity of flow through pipe,
  2. The head in metres of oil across pipe length required to maintain flow, and
  3. The power required to overcome viscous resistance to flow of oil.

10.

An oil (µ = 20 cP, ρ = 1200 kg/m3) flows through a 2.5 cm I.D. pipe 250 m long.

  1.  What is maximum flow in `m^3/s` that will ensure laminar flow ?
  2.  What would be pressure drop for this flow?

Topics

This Chapter Basics-Of-Open-Channel-Flow consists of the following topics

 An oil of viscosity 9 poise and specific gravity 0.9 is flowing through a horizontal pipe of 60 mm diameter. If pressure drop in 100 m length of pipe is `1800 (kN)/m^2`, determine:

  • The rate of flow of oil
  • The centre line velocity
  •  The total frictional drag over 100 m length
  • The power required to maintain flow
  • The velocity gradient at pipe wall
  • The velocity and shear stress at pipe wall
  • The velocity and shear stress at 8mm from wall.


;

Oil of absolute viscosity 1.5 poise and density 848.3 kg/m3 flows through a ` 30` cm I.D. pipe. If head loss in `3000` m length of pipe is `20` m, assuming a laminar flow, determine :

  1. velocity, 
  2. Reynolds number and 
  3. friction factor (Fanning??s).

;

A crude oil of viscosity `0.9` poise and relative density `0.9` is flowing through a horizontal circular pipe of diameter `120` mm and length `12` m. Calculate difference of pressure at two ends of pipe, if `785 N` of oil is collected in a tank in` 25` seconds.

;

A liquid with a specific gravity `2.8` and a viscosity `0.8` poise flows through a smooth pipe of unknown diameter, resulting in a pressure drop of `800 N/m^2` in `2` km length of pipe. What is pipe diameter if mass flow rate is` 2500 (kg)/h`.

;

A fluid of viscosity `8 `poise and specific gravity `1.2` is flowing through a circular pipe of diameter ` 100 `mm. The maximum shear stress at pipe wall is `210 N/m^2`. Find:

  1.  The pressure gradient,
  2.  The average velocity, and
  3. Reynolds number of flow.

;

A fluid of density `1200 (kg)/m^3` and viscosity `0.5 `poise is flowing at a rate of `5m^3/( min)` in a circular pipe of cross-section of `1 m^2`. Is flow laminar or turbulent? Can you predict maximum velocity of fluid in pipe ?

;

A lubricating oil of viscosity 1 poise and specific gravity 0.9 is pumped through 

a 30 mm diameter pipe. If pressure drop per metre length of pipe is `20( kN)/m^2`, determine:

  1. The mass flow rate in kg/min,
  2.  The shear stress at pipe wall,
  3.  The Reynolds number of flow, and 
  4. The power required per 50 m length of pipe to maintain flow.

;

In a pipe of 300 mm diameter, maximum velocity of flow is found to be 2 m/s. If flow is laminar,find:

  • average velocity and radius at which it occurs
  • velocity at 50mm from wall of pipe


;

An oil of viscosity `0.15 (Ns)/m^2` and specific gravity 0.9 is flowing through a circular pipe of diameter 30 mm and of length 3 m at `1/10` th of critical velocity for which Reynolds number is 2450. Find:

  1. The velocity of flow through pipe,
  2. The head in metres of oil across pipe length required to maintain flow, and
  3. The power required to overcome viscous resistance to flow of oil.

;

An oil (µ = 20 cP, ρ = 1200 kg/m3) flows through a 2.5 cm I.D. pipe 250 m long.

  1.  What is maximum flow in `m^3/s` that will ensure laminar flow ?
  2.  What would be pressure drop for this flow?

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