A better gel for shipping...TESTED!

[sbreland]

Now that's what I'm talking about. So basically it stayed 55 degrees until where it says Monday but stayed 45 or warmer for the entire trial. I know it says Sun-Mon, but how many hours are we talking from beginning of trial to the end on that one?

[Dancing frogs]

That test was from 24, Feb, 18:37, to 26 Feb, 19:17.
So just a little over two days.

[sbreland]

Nice, that was longer than I thought. So it looks like it held over 60 for about the first 24 hours and 70 for at least 16-18. This sounds like a dream and looks like this could be the answers to all of our shipping problems.

[Dancing frogs]

Getting closer...

My most recent test, a 9x9x9 homemade styro cooler made of building insulation.
Used 4 homemade gels using the phase 22, each contains the contents of 2 of the hard panel pcms.
The box can hold 3-4oz. gladware containers, weighs in at 5 lbs, and should ship priority fedex for $50
Here is the ambient test conditions:


Conditions inside box:


The spike to 86F at the beginning can be eliminated simply by waiting a little longer after preparing the pcm (hot water bath), so that they may come down to the desired temperature (this is where a temp gun really helps), as you can see, the material loses heat fairly fast above the phase change temperature.
I plan on further testing (in more realistic temps) to try to lose some of the weight, and expense of the material used.

[Dancing frogs]

Originally Posted by joshsfrogs

The phase change temp of the gel pack?

So at less than 10 degrees the package stayed above 50 degrees for over 12 hours!? I think when you factor in late night dropoff, pickup at the station, and the fact that your freezer is far more harsh than the temps seen in shipping...wow, these things are pretty sweet.

I wonder if we would want the phase change temp a little lower like 55 degrees. At 71 degrees, the phase change could happen soon after packaging and at the hub (68-70 degrees) and then be vulnerable during the rest of transit. Have it have a phase change below 60 would also allow it to gain more energy in transit during times of warming (i.e. loose energy on the tarmac, gain it in the 60 degree cargo compartment, etc.)

I think I missed this post, sorry Josh, and yes you are correct on the phase change point of the superior gels...I did a longer test using those gels, and with two gels in a small 1" thick styro cooler, in a 4F freezer, the temp fell fairly quick to 32F, but stabilized after that, and did not fall below 32F for 24 hours!
Yeah, a lower phase change point may make winter shipments more weight effecient (compared to using more phase22), however, the PCM's work both ways...once they get cold beyond their phase point, though temps will fall fast after that, they will also come back up fairly fast, until they reach phase temp, and level off again.
TCP also makes a Phase 5, which is somewhere around 40F...but again, if the temp fell low enough to get to 40, it would take alot of heat/time to get back above that temp...but would keep the contents of the box from freezing.
I am very pleased with the results of the more realistic garage tests I have done (with the phase 22) recently...have to post those one of these days...

[Dancing frogs]

Here is an example of the phase change of the superior gels:


Test was performed in a single digit (4-7F) freezer. with the gels in a standard shipping cooler.

Here is a graph showing how the phase 5 responds in the freezer. Data logger was surrounded by a mere 200g of the phase 5 in bags, then put in a similar cooler as above. Note how it took over 13 hours to get to freezing:


Not that 40 degrees is ideal for shipping frogs, but I think it shows how it would be beneficial to have a PCM with a lower phase change point for winter, as it would last longer with less material (like Josh was getting at).

[Dancing frogs]

Just had a thought...
I wonder how butter would work?