CFD Online URL
[Sponsors]
Home > Forums > Phoenics

Simulation in a laboratory. (difficulty in deciding location of inlet)

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   December 1, 2013, 09:21
Default Simulation in a laboratory. (difficulty in deciding location of inlet)
  #1
New Member
 
Selangor
Join Date: Dec 2013
Posts: 3
Rep Power: 3
otc0101 is on a distinguished road
Hi, I'm a student from Universiti Putra Malaysia. I'm a newbie in Phoenics and CFD however I was given assignment to do a simulation on laboratory air ventilation. Here i give a brief description of the lab:
A tall building, with 2 doors on ground (always open), 1 door facing empty space while the other door is facing passage between other labs.
there are few windows at top of the left and right walls of lab.

a) I'm having confusion which door/window should i set as inlet/outlet. From my point of view, I would say the door facing empty space is inlet while the other door and windows on top are outlet. Anyone mind to clarify me for this?

b) In PHOENICS, if i wish to simulate a fan, do i have to use FLAIR in PHOENICS or just CORE, then there will be an option in Object as fan?

c)any rule of thumb to determine inlet and outlet velocity? i will assume outside temperature (weather) as inlet temperature, but i had no clue on inlet velocity, outlet temperature and velocity

Thank you for time in advance for reading and answering.
otc0101 is offline   Reply With Quote

Old   December 9, 2013, 04:04
Default
  #2
Member
 
Roman Gobitz-Pfeifer
Join Date: Dec 2009
Location: Stuttgart
Posts: 74
Rep Power: 7
Wikie is on a distinguished road
Hi,

lets see if we can get some light into the darkness :-)

a) It's up to you which window/ door you define as inlet resp. outlet. In this case it's also possible to define all windows / doors as outlets. If so, you have to define the external pressure at each outlet. The volume flow will be a result of the pressure difference between the outlets.

b) You can also use Core, it also includes fan objects. In general I would prefer Flair to do indoor simulations - if it's available for you.

c) If you're using outlets for all windows /doors you don't have to define the inlet velocity, it will be a result of the pressure difference.

cheers
wikie
Wikie is offline   Reply With Quote

Old   December 9, 2013, 05:09
Default
  #3
New Member
 
Selangor
Join Date: Dec 2013
Posts: 3
Rep Power: 3
otc0101 is on a distinguished road
Thank you for the reply, Wikie. Too bad, I have no idea how to define pressure in the lab and pressure outside the lab. Mind to give any guide? If in the end I couldn't get any information, my last resort will be using inlet with velocity based on wind speed
otc0101 is offline   Reply With Quote

Old   December 9, 2013, 07:59
Default
  #4
Member
 
Roman Gobitz-Pfeifer
Join Date: Dec 2009
Location: Stuttgart
Posts: 74
Rep Power: 7
Wikie is on a distinguished road
Hi,

you don't have to define the pressure inside the lab, it's relative to the outside pressure.
If you're going to use the wind velecity as inlet velocity you should place your inlets at that building side which is facing towards the wind direction and your outlets at the leward side of your building.

cheers
wikie
Wikie is offline   Reply With Quote

Old   December 9, 2013, 08:16
Default
  #5
New Member
 
Selangor
Join Date: Dec 2013
Posts: 3
Rep Power: 3
otc0101 is on a distinguished road
Once again, thank you. I will try to figure out the way to create pressure difference.
otc0101 is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Difficulty in calculating angular velocity of Savonius turbine simulation alfaruk CFX 8 December 3, 2013 17:51
transient simulation of a rotating rectangle icesniffer CFX 1 August 8, 2009 08:25
Convective Heat Transfer - Heat Exchanger Mark CFX 6 November 15, 2004 16:55
what the result is negatif pressure at inlet chong chee nan FLUENT 0 December 29, 2001 06:13
Inlet diffuser of ramjet Mohammad Kermani Main CFD Forum 25 December 29, 2000 19:46


All times are GMT -4. The time now is 19:39.