Does humid air rise or drop?

[rick12string]

I have been under the impression that humid air rises and the RH would be higher at the top of a humidor. I have a 150 count desktop with a tray. All the slots in the tray are not blocked by cigars in order to allow air flow. I have 2 rectangular humidifiers, filled with beads in the bottom of the humi, one on each side standing on their sides facing inward.
Under the tray the RH is 65% and above the tray the RH is 62%. I checked with two digital hygrometers, put them side by side on top and they both read 62% so I know they agree. Even tried switching them when checking the RH above and below the tray with the same result, 65% below and 62% above.
Did I have this backwards all this time and it’s actually more humid at the bottom of a humidor as opposed to the top?
It’s not that big a deal but just curious. :dunno:

 

[RonC]

humidity does rise

 

[Starz26]

[ame]http://en.wikipedia.org/wiki/Humidity[/ame]

 

[openendstraight]

Great question. Humid air obviously contains water molecules, which makes it dense, so most may think humid air falls, and therefore humidification systems should be placed at the top of a humidor. In reality, eventhough humid air is dense, water molecules are still lighter than air molecules, which means humid air actually rises. This is commonly overlooked by ciagr smokers.

Since humid air actually rises, it is important to keep electronic humidification devices at the bottom of your humidor. The humid air from the humidifier will rise and humidify your cigars evenly.

Hope this helps! :ccool:

 

[rick12string]

Thanks, I didn't think I was crazy (well that's a matter of opinion) but now to figure out what's up with that humi or screw it because it probably will make me crazy. lol

 

[funkejj]

In my walk in the top shelf is the driest then they increase as it goes down so the bottom stays 65% and the top with out fan runs 60%

 

[Danilo]

I too have 2 digital hygros, and they both read the same if left next to each other, and I had both in my small humi at the same time, and the top one was 2% lower than the bottom one (only 4 inches apart height wise)

 

[Starz26]

Increasing humidity actually decreases the density of the air....Once of the hardest things for me to get through my head when I was studying for my pilots license as I always thought the opposite.

 

[openendstraight]

Keep in mind we are talking about a controled enviroment compared to outside weather. Also if your beads are on the bottom, this could be a factor. Are you using a fan?

 

[RonC]

In my walk in the top shelf is the driest then they increase as it goes down so the bottom stays 65% and the top with out fan runs 60%

temperature is an issue in this case. as temp rises, relative humdity goes down. JJ, put a hygrometer on the floor of your walkin, and check out the TEMPERATURE reading. Then place that same hygrometer close to the ceiling. I bet you see a 2 or 3 degree difference with temp near the top higher than on the floor.

that 2 or 3 degree difference can make humidity levels vary buy at least 5 %.

 

[petroleumengineer]

Great thread. In my vino I see the same thing. It has always been 2-3% lower at the top than the bottom so I figured roll with it. CC's top and NC's towards the bottom.

I also do have most of my beads below the bottom shelf too though which probably helps it stay more humid down low.

 

[Barndog]

Thanks for the information guys.I will be putting this to use today.

 

[Kurtdesign1]

Lets throw this classic variable into the discussion: If temperature effects relative humidity, can we assume (using the above example) that the 60%Rh on the top shelf is still the proper amount of humidity for the tobacco to maintain proper hydration? OR... Can we assume that the 63 degree & 65%Rh lower shelf is too moist for the average smoker; assuming, of course, that 65/65 is the preferred level? I love playing devil's advocate and provoking all to see all sides.

 

[Starz26]

Lets throw this classic variable into the discussion: If temperature effects relative humidity, can we assume (using the above example) that the 60%Rh on the top shelf is still the proper amount of humidity for the tobacco to maintain proper hydration? OR... Can we assume that the 63 degree & 65%Rh lower shelf is too moist for the average smoker; assuming, of course, that 65/65 is the preferred level? I love playing devil's advocate and provoking all to see all sides.

Well lets see if i can get this right.

If we talk about absolute volume say 1cc of water in 65f temp being 65% RH then if the air warms and rises with the same volume of water the RH should decrease as the capacity of the air to hold water increases.

Similarly, as the air cools and falls to the bottom, the RH will increase as the ability of the air to hold water decreases.

Think of it in terms of percentages. Warm air can hold more so the same 1cc of water is less of a percent of the total than it is in cold air which can hold less.

I am not sure that all this actually happens to a significant degree in a humi cabinet but oust fans do help.

of course this mayhelp as well....[ame]http://en.wikipedia.org/wiki/Relative_humidity[/ame]

 

[openendstraight]

Lets throw this classic variable into the discussion: If temperature effects relative humidity, can we assume (using the above example) that the 60%Rh on the top shelf is still the proper amount of humidity for the tobacco to maintain proper hydration? OR... Can we assume that the 63 degree & 65%Rh lower shelf is too moist for the average smoker; assuming, of course, that 65/65 is the preferred level? I love playing devil's advocate and provoking all to see all sides.

You are comparing relative humidity, absolute Humidity, and specific humidity

Also something we are not taking into effect is the air pressure.If you use wine fridges like I do (Mine stay about 5 degres blow the room temp even when not plugged in) they have a very thight seal, and will have a slightly different air pressure than the room itself, thus haveing an effect on the humidity.

 

[RonC]

excuse me while i go throw up.

 

[openendstraight]

excuse me while i go throw up.

:dunno:

 

[RonC]

:dunno:

LOL, just a little sick humor. while its fun, sometimes this stuff gets so techincal that its hard to understand

 

[Kurtdesign1]

I'm sure Ron is alluding to the fact that Rh, Ah & Sh is an oft discussed "serious" cigar thread posted throughout the history of cigar boards. It never goes anywhere & is most likely to become a bone of contention among posters. Perhaps I shouldn't have brought up a silly, annoying FOG joke.

:bottle:

 

[RonC]

I'm sure Ron is alluding to the fact that Rh, Ah & Sh is an oft discussed "serious" cigar thread posted throughout the history of cigar boards. It never goes anywhere & is most likely to become a bone of contention among posters. Perhaps I shouldn't have brought up a silly, annoying FOG joke.

:bottle:

that just about sums it up. you wind up understanding the humidity aspect, then varying temps get introduced, then something else has to be considered.