I need a help

[smcsaminda]

Hi All,
I'm a junior mechanical Engineer and new to this forum.
I'm designing a SHEVS (Smoke and Heat Exhaust Ventilation System). I collected the guidance from given by BS 7346, NFPA 92 B, Simplified Method for designing a Mechanical Smoke Exhaust System for high-rise building etc.
my building is a 10 floor building whose floor area is around 3500 square meter each. a floor consists of about 10 nos of office rooms and they are connected to a corridor. there are no balcony. fire staircases are located inside the building. All doors and staircases have been designed according to the BS 9999. All doors are connected to door closers.
If a fire started in a room occupants come out from that room to corridor and evacuate through the staircase. my plan is to extract smoke from corridor area to help for a safe evacuation. A vertical shaft is used as the smoke extraction shaft. And simultaneously staircases are pressurized. I have some issues as follows,
1. When I create a fire in a room, do I need to keep the door of that room opened?
2. When I calculate extraction rate manually, how can I do that? How do I calculate the smoke spills through the door.
please help me...

 

[sprinkler1000]

First of all, I would recommend checking local building code for the requirements.
For a high rise what is typically required is stairwell pressurization.

 

[smcsaminda]

Thank you Mr.sprinkler1000,for your idea. I checked our local code.
That also recommend to go for a Smoke Extraction System. But it also says that our system should comply with the BS 7346 code. As I understood the code, It does not discuss that manner (whether we want to assume that the office door is opened or not). My major problem is that when I do a CFD simulation (or manual calculation) for a created fire in the office room, do I need to keep open the door of that room?

 

[317069]

why do you want to calculate extraction rate?

 

[irfansiddiqui]

consider the door open as If the fire starts the occupants will not bother to close the door during evacuation. And stay confident on your design. mean while try to search out for any code which recommends the closed door strategy as it will save your consumption & Investment cost

 

[smcsaminda]

Thank you for your comments.
If one of you have faced this problem and have found solid answer or method please help me.

thank you.