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Participant

Join Date: Jul 2012
Posts: 2

### Calculation of Pressure Drop in PF-Heat Exchanger (Condenser)

07/05/2012 3:19 AM

Hi every one~!!

Recently I am working on making 1-D simulation program for PF condensers performance. And I want to consider the effect of pressure dop in condenser performance.To do so, I approached to calculate tube-side pressure drop using Darcy's equation with f-smoth tube, turbulance. But calculations of pressure drop in Header side and in&out nozzles are confusing and challenging. For header side I found equation that is " K(G^2/2ρ)n=△P,n= number of tubes, K=1.6(two or more tubes side). is it applicable for condensers. I know I should apply two-phase pressure drop but I want to skip considering 2 phases for pressure drop calculation since I will use mean values of density and viscosity in 0-1 quality. the objective condenser has 5passes

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Guru

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing. Kettle's on.
Posts: 19572
#1

### Re: Calculation of pressure drop in PF-Heat exchanger(Condenser)

07/05/2012 3:31 AM

Whoa, there!

• If PF stands for plate-and-frame, why is there any consideration of <...tubes...>? If it doesn't then please define PF; the electrical fraternity would think 'power factor', which is irrelevant.
• And if the thing is condensing, i.e. vapour into liquid, that's another kettle of fish, so to speak. The thing is dealing with two-phase flow.
• And if there are equations to be written, please do the forum the decency to define the meaning of the variables while they are being used.

Many thanks.

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Participant

Join Date: Jul 2012
Posts: 2
#2

### Re: Calculation of pressure drop in PF-Heat exchanger(Condenser)

07/05/2012 7:59 AM

"PF heat exchanger" is plate-fin heat exchanger. sorry for confusing you.

Yes, it should be dealing with 2 phase pressure drop. I am working on that.

Before dealing with 2 phase pressure drop, I wondered how different result it yields without consideration of 2 phase pressure drop and whose equation I need to introduce to solve 2 phase pressure drop.

Guru

Join Date: Nov 2007
Posts: 512
#3

### Re: Calculation of Pressure Drop in PF-Heat Exchanger (Condenser)

07/06/2012 8:56 AM

The pressure drop has to be the same across each tube right? Just divide the flow evenly amongst all tubes and calculate the pressure drop going through one tube. It's a pipe at this point.

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