Bernoulli's Equation

[tom4798]

Hi Everyone,

I cant get my head around this one,

This isn't the question in the assignment but if I knew this one it would help me with answering it.

How can you apply bernouilli's equation to solve simple problems associated with pipe and ductwork systems and devices? 

Any help would be greatly appreciated!

Edited May 13, 2019 by tom4798

[studiot]

1 minute ago, tom4798 said:

Hi Everyone,

I cant get my head around this one,

How can you apply bernouilli's equation to solve simple problems associated with pipe and ductwork systems and devices? 

Any help would be greatly appreciated!

 

0) Also use the continuity equation, in combination with Bernoulli.

1) Use Bernoulli's equation in the form of pressure head between known points in the system. Remember Bernoulli applies to steady flow.

2) Remember for ductwork that air is compressible so the work will not be simple.

3) If the system has machines such as pumps then break it into sections and add a head term for the machine.

4) If the system includes heatflow use the 'Constant flow equation' version of Bernoulli or The First Law of Thermodynamics (which are the same thing = conservation of energy)

[tom4798]

1 minute ago, studiot said:

Thank You

0) Also use the continuity equation, in combination with Bernoulli.

1) Use Bernoulli's equation in the form of pressure head between known points in the system. Remember Bernoulli applies to steady flow.

2) Remember for ductwork that air is compressible so the work will not be simple.

3) If the system has machines such as pumps then break it into sections and add a head term for the machine.

4) If the system includes heatflow use the 'Constant flow equation' version of Bernoulli or The First Law of Thermodynamics (which are the same thing = conservation of energy)

 

[studiot]

Have you any particular problems in mind?

[tom4798]

Just now, studiot said:

Have you any particular problems in mind?

It was just a part of a task I was set, the question I've been told to answer is "How do you justify the selection of fans, pumps & compressors?" which I'm not sure.

[studiot]

The principal characteristics are capacity (flow rate) and pressure drop.

These slot nicely into the continuity and Bernoulli equations.

Other than that you might consider the material transported eg explosive gas, water or concrete and the operating temperature.