vinhermes
Marine/Ocean
- Aug 29, 2009
- 36
Dear Community,
I have made a vb.net application allowing me to get pipe and fittings losses. From here, all is good. I am using either Darcy laminar equation or Serghide's explicit solution for the Colebrook equation when relevant.
From here, all is still good and results comparisons with litterature and other availabe softwares is really nice.
From here, all is not so good anymore...
I want to add to the losses results: the altitude difference between inlet and outlet as well as the pressure required at outlet to find the pump power and characteristics needed.
My question may seem dumb and I am sorry for this but I am not English and get a bit confused with all these terms and units.
So my pipe and fittings friction losses are expressed in meters (is this meter liquid column, meter water column, meter head? My guess is the first one and last one, both, but really unsure...)
My altitude difference is expressed in meters
My pressure required at the outlet is expressed in bar.
I have got a choice between different medias, relevant in the shipping industry (in which I am employed) and these have different densities ( lube oil, fuel oil, water, wastewater, sea water, etc.). These densities are of course already involved in the friction calculations.
Can you please confirm me that to get conscistency with the units, I need to:
- convert my meters head for the friction losses in bar, using formula 2
- convert my altitude difference in bar, using formula 2
- convert my pressure required in bar, using forumula 2
And from there convert to get MLC units (using formula 1) to get the pump particulars.
The formulae used are:
h(m) = Pressure (bar)/(density(kg/m3)x9,81x10^-5)
P(bar) = (density (kg/m3)x9,81xh(m))/10^-5
I would be so grateful if you could confirm me this. Thanks by advance and please, if you need any other information, I would be glad to provide these. Vincent
I have made a vb.net application allowing me to get pipe and fittings losses. From here, all is good. I am using either Darcy laminar equation or Serghide's explicit solution for the Colebrook equation when relevant.
From here, all is still good and results comparisons with litterature and other availabe softwares is really nice.
From here, all is not so good anymore...
I want to add to the losses results: the altitude difference between inlet and outlet as well as the pressure required at outlet to find the pump power and characteristics needed.
My question may seem dumb and I am sorry for this but I am not English and get a bit confused with all these terms and units.
So my pipe and fittings friction losses are expressed in meters (is this meter liquid column, meter water column, meter head? My guess is the first one and last one, both, but really unsure...)
My altitude difference is expressed in meters
My pressure required at the outlet is expressed in bar.
I have got a choice between different medias, relevant in the shipping industry (in which I am employed) and these have different densities ( lube oil, fuel oil, water, wastewater, sea water, etc.). These densities are of course already involved in the friction calculations.
Can you please confirm me that to get conscistency with the units, I need to:
- convert my meters head for the friction losses in bar, using formula 2
- convert my altitude difference in bar, using formula 2
- convert my pressure required in bar, using forumula 2
And from there convert to get MLC units (using formula 1) to get the pump particulars.
The formulae used are:
h(m) = Pressure (bar)/(density(kg/m3)x9,81x10^-5)
P(bar) = (density (kg/m3)x9,81xh(m))/10^-5
I would be so grateful if you could confirm me this. Thanks by advance and please, if you need any other information, I would be glad to provide these. Vincent
