[cerez]

Hi everyone i have a question with hose pressure drop analysis.
I am doing try to find rubber hose pressure drop on intake system.
Material:Air
flow:turbulance
Pressure based

inlet boundary condition
mass flow:0.1kg/s
Temperature of fluid:200C
pressure 165kPa

I dont know what should i write on outlet boundary condition.
Please if u know the answer help me. Sorry for bad english

[lcarasik]

Originally Posted by cerez

Hi everyone i have a question with hose pressure drop analysis.
I am doing try to find rubber hose pressure drop on intake system.
Material:Air
flow:turbulance
Pressure based

inlet boundary condition
mass flow:0.1kg/s
Temperature of fluid:200C
pressure 165kPa

I dont know what should i write on outlet boundary condition.
Please if u know the answer help me. Sorry for bad english

Use a mass flow rate inlet and a pressure outlet. Why aren't you just doing this with a hand calculation?

[LuckyTran]

Two ways.

1) Mass-flow inlet and a pressure outlet, with the outlet pressure of 165 kPa. This is the most robust way.

2) Other way is to do a pressure inlet with inlet pressure of 165 kPa. Use a presssure outlet with the targeted massflow rate outlet. This is slightly less numerically robust but should also work.

It's just a question of whether you want to fix the inlet pressure or outlet pressure to 165 kPa. Also keep in mind that at inlets you're specifying the total/stagnation pressure (not the static pressure).

[cerez]

Originally Posted by lcarasik

Use a mass flow rate inlet and a pressure outlet. Why aren't you just doing this with a hand calculation?

Because geometry is comleks for me

[cerez]

Originally Posted by LuckyTran

Two ways.

1) Mass-flow inlet and a pressure outlet, with the outlet pressure of 165 kPa. This is the most robust way.

2) Other way is to do a pressure inlet with inlet pressure of 165 kPa. Use a presssure outlet with the targeted massflow rate outlet. This is slightly less numerically robust but should also work.

It's just a question of whether you want to fix the inlet pressure or outlet pressure to 165 kPa. Also keep in mind that at inlets you're specifying the total/stagnation pressure (not the static pressure).

Thank you for your answer. I am try to execute old analysis with same geometry and same inlet boundary condition but i dont have outlet condition.
i try almost every outlet boundary condition with the program that i use with.
i use scflow14. i will add a picture on the below that i can not fine pressure distribution on the hose. inlet.PNG

Pressure.png

Outlet boundary condition.PNG
by the way i am using air(incompressible) as a fluid.

[cerez]

I found the solution i should have write outflow B.C to -0.1kg/s mass flow and inlet to 165kPa.

After i analysis i found the almost close result. like 2kpa pressure drop