Stack Effect+Wind Chap4

Question 1

What term ———-is used to describe the movement of air throughout a building that occurs when temperature of the interior of the building is different than the temperature of the external environment. This happens in all buildings, including PD’s.
Which type building is this significantly more prominent?
1.1

Answer 1

Stack effect

High-rise buildings

Question 2

Stack affect encompasses two distinct dynamics which are? 1.2.

Answer 2

Internal vertical air movement inside the building
Horizontal air movement

Question 3

Stack Effect
Near the ——- of the building there will exist an area they experiences no horizontal air exchange at all. This area is called the?
1.4.1

Answer 3

Center of the building

Stack effect neutral pressure zone.

Question 4

Stack effect neutral pressure zone.
Horizontal air movement, the stronger the stack effect, this means that lateral air movement will be strongest at openings of ——- our locations on the ———- and ——-. 1.4.2.

Answer 4

Windows
Uppermost and bottom most floors

Question 5

Stack effect will be more prominent in ——— weather. 1.5.1 a.

Answer 5

Extreme weather
When air conditioning or heating systems, make the temperature inside the building remarkably different from the outside temperature.

Question 6

What dictates the magnitude of the stack effect
1.5.1

Answer 6

Size of the temperature differential between the interior and exterior and the height of the building

Question 7

Stack effect
——- buildings will experience a more powerful stack effect.
1.5.1 B

Answer 7

Taller buildings
because more air will be moving over a longer distance inside the building

Question 8

Direction of the stack effect.
Positive stack effect is in what season?
Negative stack effect is in what season?
1.6.1

Answer 8

Positive is in winter
(building is warmer than the external environment)

Negative is in summer
(building is cooler than the external environment
** good chart on 4-2

Question 9

Positive stack effect (winter)
As a result, air and smoke movement inside the building will travel ———- via vertical shafts and attempt to exit the building via available openings near the ——— of the building.
1.7.1 B

Answer 9

Upwards

Top

Question 10

Positive stack effect (winter)
A fire on an upper floor will tend to want to vent ————?

A fire on the lower floor will tend to ——- ?
1.7.1 CD

Answer 10

Out the windows

Draw air into the windows, creating conditions similar to wind impacted fires

Question 11

Negative stack effect (summer)
Is also known as?
1.7.2

Answer 11

Reverse stack effect

Question 12

Negative stack effect (summer)
A fire on an upper floor will tend to ——- the windows, creating conditions similar to wind impacted fire.

A fire on a lower floor will tend to want to —— out the windows.
1.7.2 DE

Answer 12

Draw air into

Vent out

Question 13

Negative stack effect (summer)
In NYC, the difference between the temperature inside a building compared to the temperature outside the building will be —— during the winter months than it will be during the summer months.
1.7.2 note

Answer 13

Greater
PS for this reason, the positive stack effect will occur during the winter will be more prominent than the negative stack effect which occurs during summer months.

Question 14

Fire dynamics
Of all the conditions that can affect fire behavior, ——- has the most dramatic impact.
2.1

Answer 14

Wind