Pressure vs Velocity Simplified

Why would you need the answer ASAP if this is only to tell your brother, if you ever have to...this isn't homework is it ??

The simplest formula I know of for this is the Darcy-Weisbach formula. Unfortunately, this and other formulas depend on the density and viscosity of the fluid being pumped, and the roughness of the pipe. Because of these multiple factors, this whole question is not simple.

(If you think D-W + Moody + Reynolds is bad, check out the Hazen-Williams or Colebrook formulas instead.)

http://en.wikipedia.org/wiki/Bernoulli%27s_principle

Without clarification it's impossible to tell what you're asking, for homework, brother or whatever.

And how dare you suggest we're mechanical lovers?

Codey

Dear friend,

Total Energy = PE+ KE+pE+Friction losses

where,

PE= Potential Energy (i.e. energy due to position),

KE= Kinetic Energy (i.e. energy due to motion),

pE= Pressure Energy (i.e. energy due to compression), and

Friction losses are the energy lost due to friction, rigidity etc.

When you restrict the opening, the fluid (water) tends to maintain its maximum flow rate by increase in its speed which makes it to cover a longer distance.

Regards.

Why you have to bring your brother into it?

It is simple.

You have a pipe (Horizontal, vertical does not matter)

Inlet Pressure (what ever is pushing the water into it pump, gravity,..) = P_i

Out let pressure P_o= P_i - δP

What is δP and what is it dependent upon?

When you close the outlet (fully or partially) what happens to these factors and hence what happens to δP ?

And thereby what happens to P_o ?

Then use the great Bernoulli's theorem at your fingertip (that's what you use to close the pipe isn't it ?)

Balance the heads and you will see what happens to each of the parameters that constitute the heads.

Is it sufficient guidance to do the Home work?

BTW: I agree with the earlier post

1. This is a question of hydraulics/ fluid mechanics and not exactly mechanical.

2. We are not mechanical lovers