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srs22
Jan8-11, 09:53 PM
Hi,

I am currently trying to do a project for my final year in engineering.I have not been able to find any software thats helping me in simulating and obtaining results for pressure drop through an orifice plate.

i have tried the fluid option in ansys v10 dinn't understand how to use it properly its giving stress concentration due to fluid pressure than pressure drop through the orifice plate

is there any open source software that will help,ANSYS 12 and 13 are too costly


orifice plate:
1}inlet dia is 1cm
2]outlet is 0.5 cm
3]inlet pressure is Atmospheric 101.3 Kpa
4]inlet velocity is 30km/hr or 8.3m/sec

i need to find outlet pressure,velocity and temperature drop from inlet to outlet


theoretically Bernoulli's principal can be used but either V(outlet) or p(outlet) is required



any help is appreciated,

THank you :)

Q_Goest
Jan9-11, 07:22 PM
Flow through an orifice is calculated in various ways depending on whether the fluid is gas or liquid and whether it might be choked flow. Equations can be found here:
http://www.air-dispersion.com/usource.html

Equations and an online calculator can be found here:
http://www.lmnoeng.com/Flow/SmallOrificeGas.htm

Regarding temperature drop through an orifice, we generally assume the pressure drop is isenthalpic. To get fluid properties for real fluids you should use a fluids properties database. Note that a temperature drop won't be predicted for an ideal gas or a perfectly incompressible fluid.

srs22
Jan10-11, 01:00 AM
Flow through an orifice is calculated in various ways depending on whether the fluid is gas or liquid and whether it might be choked flow. Equations can be found here:
http://www.air-dispersion.com/usource.html

Equations and an online calculator can be found here:
http://www.lmnoeng.com/Flow/SmallOrificeGas.htm

Regarding temperature drop through an orifice, we generally assume the pressure drop is isenthalpic. To get fluid properties for real fluids you should use a fluids properties database. Note that a temperature drop won't be predicted for an ideal gas or a perfectly incompressible fluid.

thanks for the reply :)

so theoretically using those formulas i can solve and get my required answer..but is there a software that will help me simulate this and show it as a presentation using software like ansys or some thing similar

Q_Goest
Jan10-11, 06:34 AM
I'm sure there's software that can do it but I'm not familiar with it. Just seems like a lot of effort to use a CFD software package when it can be done in seconds on a spreadsheet.

Jobrag
Jan10-11, 09:01 AM
Try looking at ASME PTC 19.5 (it should be in your college library).

srs22
Jan11-11, 09:07 AM
thanks for the replies :)

srs22
Jan13-11, 09:39 AM
if i am getting a pressure drop from 101.3Kpa to 37.5Kpa
and increase in velocity from 8.33 m/s to 33.33 m/s

what kind of temperature drop can i expect ?

i looked through Google,dint get satisfactory results..i saw some charts of pr density vs temperature i couldn't infer much

srs22
Jan13-11, 09:42 AM
I'm sure there's software that can do it but I'm not familiar with it. Just seems like a lot of effort to use a CFD software package when it can be done in seconds on a spreadsheet.

i have to compare theoretical and computer generated results to prove what i have done is right,so a simulation of flowing fluid will be and changes in temperature,pressure,velocity has be shown...i will try using Fluid option in ANSYS 10 or i have to learn how to use fluent software in ANSYS 12