Myth Busters – Relative Humidity

[strife]

Seem like sound logic so far?

Sounds good, can I steal this for my nephews 4th grade science project? okemyeye

Yep, a vodka expert was able to determine the order of quality from the crap vodka, through the various rounds of crap vodka thru the filter, and the good vodka.

Good thing my friends aren't experts! :bottle:

 

[Andytex]

This is extremely interesting and I am learning everyday I log on to this place. Thank you BOTL.

 

[kockroach]

Hey Mitch, I found the following page...which is a class lesson on humidity and dew point.

http://www.faqs.org/faqs/meteorology/temp-dewpoint/

There are a bunch of equations, so some of it is a bit over the top, but most interesting is this from the introduction section:

If you have a closed container with water and air (like a beaker) then there an equilibrium will develop, where the air will contain as much vapor as it can.

So the closed container is going to affect the experiment. It should reach an equilibrium, but it will be dependent upon the amount of total water in there, as well as the temperature and the pressure. Pressure at different altitudes will affect the RH for a given temperature. Both pressure and temperature will affect the density of air, which can affect the vapor pressure. If I understand things correctly.

 

[Danilo]

Really like the way you are doing this!!
Looking forward to all the results.


I'll be a guinea pig :chat:

 

[Mitch]

Hey Mitch, I found the following page...which is a class lesson on humidity and dew point.

http://www.faqs.org/faqs/meteorology/temp-dewpoint/

There are a bunch of equations, so some of it is a bit over the top, but most interesting is this from the introduction section:

If you have a closed container with water and air (like a beaker) then there an equilibrium will develop, where the air will contain as much vapor as it can.

So the closed container is going to affect the experiment. It should reach an equilibrium, but it will be dependent upon the amount of total water in there, as well as the temperature and the pressure. Pressure at different altitudes will affect the RH for a given temperature. Both pressure and temperature will affect the density of air, which can affect the vapor pressure. If I understand things correctly.

I think that is true if only air is present, but I've also found writings (over the top as well) that talk of rate of saturation or absorbtion coeficients. I think the point being that diffirent materials seek out a diffirent equalibrium.

Should this be simpler?

 

[Mitch]

OK, ran into the first snag. But in the bag of beads yesterday and found condensaion on the inside of the container this morning with RH of 74 and temp of 94. I wiped up about a table spoon of water and will keep checking. One cigar's wraper got a little wet from where it was sitting.

 

[Danilo]

OK, ran into the first snag. But in the bag of beads yesterday and found condensaion on the inside of the container this morning with RH of 74 and temp of 94. I wiped up about a table spoon of water and will keep checking. One cigar's wraper got a little wet from where it was sitting.

Would this be due to the beads not reacting fast enough to the amount of humidity? do you think the size of the container has to do with it?

 

[SmokeProper]

Sweet.

 

[PLUSH]

Mitch,

I did something similar to this years ago. I took 3 same cigars (for consistency, and to limit variance) I took three air tight sealed containers that I had prepped with 69% Boveda packets for a week trying to reach a stable equilibrium. I then inserted each of the cigars into the separate containers with three calibrated hygrometers. One I place in the freezer (0), one in the fridge (35) and one outside (90-100), and of course the one I kept in my humi inside t 68/68. from what I remember, the one in the freezer, was frozen (duh) and did not smoke that well. Any humidity in the cigar was frozen. As for the others I seem to remember that they smoked well. The humidity seemed to stay consistent as each of these was in a fairly small container.


I look forward to seeing what you discover as well.

 

[Mitch]

Would this be due to the beads not reacting fast enough to the amount of humidity? do you think the size of the container has to do with it?

My guess is that I had the box off heat for too long messing with it and it cooled down to room temperature causing the condensation. it's been on ever since and seems to be doing fine.

 

[Mitch]

First post updated, they are equalizing to the temp RH now. I'll give them a few more days before I make any judgements.

 

[Mitch]

First Post updated, not much to report, cigars are aboout back to starting point in weight and feel, but at 94 degrees.

 

[DeeDubya]

I've noticed the effects of temperature in my walk-in. The humidistat that controls the humidifier responds to the moisture level in the air. So as the temps drop in cooler weather it seems to cycle more often and run longer cycles to maintain the set RH. Of course the ambient air is also drier which would account for part of the problem.

Unlike a passive type humidifier the Honeywell that I have must cycle on and off to maintain a constant. There is an inherent "differential" between on and off so it will normally have a +/- 5% swing. My experience is that a low of 65% and high of 70% seems to be about right while keeping the temperature between 65F and 70F.

 

[Mitch]

I've noticed the effects of temperature in my walk-in. The humidistat that controls the humidifier responds to the moisture level in the air. So as the temps drop in cooler weather it seems to cycle more often and run longer cycles to maintain the set RH. Of course the ambient air is also drier which would account for part of the problem.

Unlike a passive type humidifier the Honeywell that I have must cycle on and off to maintain a constant. There is an inherent "differential" between on and off so it will normally have a +/- 5% swing. My experience is that a low of 65% and high of 70% seems to be about right while keeping the temperature between 65F and 70F.

Do you think the temp drop could be making your seal not as good, or making the air outside the humidor drier from heating?

 

[Mitch]

First Post updated. Cigars seem to be stabalized at 93 degrees and 68 RH.

I'm thinking about changing up the second part of the test with the Oasis. I think I'm going to put one in that is about half full, but not turn it on for the first couple of days. I'm woundering how well the Oasis does at not raising humidity when not turned on. If it rises, I'll take the Oasis out. But, I'm starting to wounder if the air gets "hungry" so to speak when it gets warm, will it go over 70% just from evaporation. I know this is an extreme test, but I think many people have experienced finding an Oasis empty and RH very high, so I want to test if this happens and how quickly a peak temperature could cause it, if so.

 

[L8A]

Great experiment Mitch and one of the best threads I've read. Some really good input from others as well.

 

[DeeDubya]

Do you think the temp drop could be making your seal not as good, or making the air outside the humidor drier from heating?

I've got it sealed as well as can be. This is an 800 cubic ft room and every time I open the door I get an air exchange. My reasonable objective is to keep the temp at 70 or below and the RH between 65% & 70%. It's the 100+ summers that cause most of my grief. The A/C has to cycle to keep the temps down but of course this dehumidifies so then the humidifier has to work overtime to keep up.
IMO most cigars burn more evenly, draw better and are less likely to bust a wrapper if kept at 65%.

 

[IndyPaintballSmoker]

I would never keep sticks at RH
Mythbusters are not always right!

 

[Robinsond]

Very scientific! Can't wait to see results

 

[Danilo]

I would never keep sticks at RH
Mythbusters are not always right!

I don't get it... if you don't keep em at a RH level... how do you keep em?
Am I missing something?