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## Main Question or Discussion Point

0http://math.stackexchange.com/questions/946493/solve-for-pressure-drop-across-and-orifice# [Broken]

I'm running 1/2" pipe but the only way to connect a 9/16" flow switch is with a 1/4" adapter. I'd have to go from 1/2" down to 1/4" to the 9/16" flow switch down to 1/4" back to 1/2".

I was wondering if this would cause a large pressure drop but I used this online calculator and was wondering if anyone could verify these numbers:

Calculation output

Flow medium: Water 20 °C / liquid

Volume flow: 2 l/min

Weight density: 998.206 kg/m³

Dynamic Viscosity: 1001.61 10-6 kg/ms

Element of pipe: Orifice sharp-edged

Dimensions of element: Diameter of pipe D1: .5 in.

Diameter of pipe D2: .25 in.

Velocity of flow: 0.86 ft./s

Reynolds number: 3330

Velocity of flow 2: 3.45 ft./s

Reynolds number 2: 6661

Flow: turbulent

Absolute roughness:

Pipe friction number:

Resistance coefficient: 30.68

Resist.coeff.branching pipe: -

Press.drop branch.pipe: -

Pressure drop: 22.14 lbw./sq.ft.

0.15 psi

I've also looked at a flow rate calculator and was wondering if the down size in the piping would affect the flow rate substantially? I'm really trying to stay at 2L/min.

I'm running 1/2" pipe but the only way to connect a 9/16" flow switch is with a 1/4" adapter. I'd have to go from 1/2" down to 1/4" to the 9/16" flow switch down to 1/4" back to 1/2".

I was wondering if this would cause a large pressure drop but I used this online calculator and was wondering if anyone could verify these numbers:

Calculation output

Flow medium: Water 20 °C / liquid

Volume flow: 2 l/min

Weight density: 998.206 kg/m³

Dynamic Viscosity: 1001.61 10-6 kg/ms

Element of pipe: Orifice sharp-edged

Dimensions of element: Diameter of pipe D1: .5 in.

Diameter of pipe D2: .25 in.

Velocity of flow: 0.86 ft./s

Reynolds number: 3330

Velocity of flow 2: 3.45 ft./s

Reynolds number 2: 6661

Flow: turbulent

Absolute roughness:

Pipe friction number:

Resistance coefficient: 30.68

Resist.coeff.branching pipe: -

Press.drop branch.pipe: -

Pressure drop: 22.14 lbw./sq.ft.

0.15 psi

I've also looked at a flow rate calculator and was wondering if the down size in the piping would affect the flow rate substantially? I'm really trying to stay at 2L/min.

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