Any1 good at Physics?

[tenacity2986]

I have a tightly sealed closet.

I am going to playce 2 4'' holes at the top of my grow room door with a vent cover so it looks like central ac/heat.

One hole will have a hose connected to an inline fan.
The other wont have anything.

What will happen if I

A) draw cool air into the growroom using an inline fan. Will the other hole push out the hot air?

B) draw hot air out of the growroom using an inline fan. Will the other hole pull in cool air?

Dont want to purchase another fan. Trying to simulate laws of physics and air pressure. Let me know which one you think would be more effective.

[Ganja Guerrilla]

yes and no

if you use a fan to pull the hot air out is correct but the intake needs to be near the bottom (hot air rises)
convection alone will help with the cool air coming from a bottom hole (hot air rising draws cool air in from below)

[J3SUS]

well as u know, heat rises, so aslong as you suck the cold air in and release it at the bottom of the room the hot air "should" just rise out of the top hole in the door. but again this depends on the height between the hole at the top of the door and the ceiling. if there is a big gap you will find a large pocket of hot air staying up top above the extraction hole. if you have a high ceiling id recommend using the fan to suck hot air out, making sure its at the highest central point in the room, if your celing is close to the hole in the door then use the fan to blow cool air in, to the bottom of the room.

[Gator01]

dont forget the advantages with a fan thats pulling air from the room to cool it. It keeps the smell of your grow out of the rest of the house by causing a negative pressure difference so no air(smell) leaves your room. Dont push air into your room or your house will reek.

[JoKRe]

a ) true

b ) false

[J3SUS]

Originally Posted by Gator01

dont forget the advantages with a fan thats pulling air from the room to cool it. It keeps the smell of your grow out of the rest of the house by causing a negative pressure difference so no air(smell) leaves your room. Dont push air into your room or your house will reek.

ok thats a fair point, but that should not be an issue if your closet is air tight sealed and you can ensure that all exiting air is leaving through that one hole. because you can then pipe that off to a suitable place.

[Spanishfly]

Cool air being denser than hot air, using the fan to blow cool air in will shift a bigger mass of air per minute than the other way round.

[tenacity2986]

how much C02 in ppm is in the air we exhale

[urgr8estfear]

Originally Posted by tenacity2986

I have a tightly sealed closet.

I am going to playce 2 4'' holes at the top of my grow room door with a vent cover so it looks like central ac/heat.

One hole will have a hose connected to an inline fan.
The other wont have anything.

What will happen if I

A) draw cool air into the growroom using an inline fan. Will the other hole push out the hot air?

B) draw hot air out of the growroom using an inline fan. Will the other hole pull in cool air?

Dont want to purchase another fan. Trying to simulate laws of physics and air pressure. Let me know which one you think would be more effective.

Originally Posted by Ganja Guerrilla

yes and no

if you use a fan to pull the hot air out is correct but the intake needs to be near the bottom (hot air rises)
convection alone will help with the cool air coming from a bottom hole (hot air rising draws cool air in from below)

Wrong!

It's yes and yes!
Push or pull doesn't really matter.
Volume of air displaced stays the same.

The only real choice you have is 2 holes at the top or 1 hole at the top and 1 hole at the bottom.
2 holes at the bottom is not a good idea, since heat rises.

I myself chose the put the fan sucking out air bottom right of the box.
The intake hole is top left.

In my box, 'cold' air falls in from the top left while 'hot' air from the bulbs goes up.
This causes the air in the box to rotate which mixes it nicely.
Again I say volume of air pulled/pushed through the box remains the same.

Ofcourse you can do holes at the top two that wil work fine.
But in that case, the kinetic energy the 'hot' air has moving up will be lost outside the box.
Instead of being used to 'rotate' the air.

I like my way best!

[Spanishfly]

Originally Posted by urgr8estfear

Wrong!

Volume of air displaced stays the same.

Not so.

Cold air is denser than warm air, so using the fan to blow in cold air will shift a greater mass of air than using it to extract warm air.

And the warmed air then exhausted will have a greater volume than the cold air blown in. It has expanded and become less dense.

[ChronicFTW]

Originally Posted by Spanishfly

Not so.

Cold air is denser than warm air, so using the fan to blow in cold air will shift a greater mass of air than using it to extract warm air.

And the warmed air then exhausted will have a greater volume than the cold air blown in. It has expanded and become less dense.

Wouldnt that also depend on weather the fan is better sucking or blowing

[urgr8estfear]

Originally Posted by Spanishfly

Not so.

Cold air is denser than warm air, so using the fan to blow in cold air will shift a greater mass of air than using it to extract warm air.

And the warmed air then exhausted will have a greater volume than the cold air blown in. It has expanded and become less dense.

Wow, you've been paying attention in class.
You're right!
The numbers of liters drawn into the box is not the same as that comes out.

And you're wrong.
This will happen regardless of wether you push in air or suck it out.
So the volume of air displaced does not differ wether the fan blows or sucks.

So Spanishfly you got the theory right, but it doesn't apply to the questing 'blow or suck'.

[youngandstupid]

Originally Posted by tenacity2986

how much C02 in ppm is in the air we exhale

A lot, I don't remember exact #s but I remember an overgrow thread where someone measured it to be so high that it's toxic levels of CO2, even for a plant. That's just hte breath itself obviously it becomes diluted the instant you exhale so the more you breathe near your plants the better.

[froggy]

if i had to make a choice, i would exhale the air out of my grow room to the outside. then u dotn get the smell inside the house. i would blow it out of the top of room b/c hot air rising and i would have open holes on the bottom of it b/c cool air is down there. this also gives u a circulation effect.

and really, it doesnt matter that much if u suck or blow. personally i prefer to get blown than to suck, but that is me. but trying to force air into a place makes things harder than sucking air out. hot or not hot air, it doesnt matter cuz equilibrium will always be taking place. even tho u cannot see it, air has mass.

how much C02 in ppm is in the air we exhale?

it depends on how fat u are, and if ur a man/woman. and if ur active or a lazy potato.

the ave man @ 150lbs at resting state puts out somewhere around 12g of co2/hr. if ur in there having sex(excersise factor = 1.7)? 2ppl x ur fat girlfriend cuz u dont have a job cuz u smoke way too much weed is 3x ur weight x ur 6minute holding power = 8.16g of co2/intercourse.

now, how much time does it take for a plant to breath in ur sex gas? that is gonna be a much longer formula. but if u need me to do that, i will need to know how many plants u have and size, weight and health. so u must rip out ur plant and weigh it, roots and all. let me know if i can be anymore help...

[tenacity2986]

lol, ur Wayyy toooo funny frooggy. got a chuckle after that one... are these tested experiments that you've tried?