Heat Loss on Cladded Sidewall
Has anyone done any measure testing....
Let's say a 4 Quart Disc Bottom (Vollroth, Atlantis, whatever) versus a 4 Quart Full Cladded Pot.
How much *heat loss* is there - whether it be surface temp on the bottom ......
A even just a potfull of water that is then put to simmer.
Are there measure statistical #'s out there...
What is the heat source? With a gas flame, some of the hot gases will flow up along the pot sides, heating the sides from the outside. An electric burner that is larger than the pot will do some of the same, On the other hand, an induction burner will only heat the bottom.
On an induction burner I can boil a few cups of water in a steel pan before the rim gets too hot to touch. On the other hand, thick aluminum, with a steel induction base, will get too hot to touch.
Hi Kaleo -
You hit it on various musings I had but could not be so concisely.
How the viscosity of the liquid would behave in pot - whether it be a cladded or non cladded sidewall pot. Or the merits of the heat on the sidewalls depending on that viscosity, or the insulating properties of it versus heat loss, etc.
All in All a good read.
I'm not really sure what you're after here, or what you're concerned about. Evaporative heat loss? Heat loss from the contents out through the wall of the pan? Hob heat that never makes it to the food? Your utility bill? Too-hot a kitchen?
Boiling water is at one end of a continuum of viscosity. At that end, convection currents in the water predominate and will even out the temperature (and within comparable timeframes) pretty much regardless of the sidewall construction. In that application, it is theoretically advantageous from a thermal perspective to have a highly conductive (or inductive) disk bottom and sidewall materials that act as an *insulator*, e.g., straight SS. However, straight SS-sidewall pans tend to have very thin walls, and so will bleed more heat than clad which uses the same total thickness of SS to clad something more conductive between it.
Nearer the other end of the continuum--thick contents--convection currents often can't develop (or strongly enough) carry the hob's heat away from the two dimensions of the pan's floor, in which case there will be--without stirring diligently--uneven cooking and perhaps scorching. In these applications, conductive sidewalls serve a purpose, to some degree converting a 2-dimensional hob to a larger, 3-dimensional one. As an example, dishes like chili can be seen to be simmering both at the bottom and *from the sides* of a very conductive pan (This can even be seen with boiling water in a copper pan, especially on gas).
There have been tussles here over the physics of where heat goes from highly conductive sidewalls. There are those who state categorically that heat only flows *out* toward the ambient kitchen air and therefore conductive sidewalls are wasteful and hot. It's my opinion that the heat conducted up the sidewalls actually goes both into the food and the air, so long as the sidewall is kept hotter than the pan's contents. I think one way to prove this might be to A-B two pans, one clad and one disk, in a simmer-to-dryness test. But you'd have to eliminate/equalize all the other variables, which would be difficult.
To some extent, the issue becomes what heat loss is it that bothers us? Is it that *hob* heat is being conducted up the walls "bypassing" the contents and radiating out into the kitchen? Or is it that the heat in the *food* is being "stolen" and conducted laterally? I think you can see it becomes abstruse very quickly.
A final point is cost of materials and manufacturing technology. The manufacturers have strong incentive to minimize the use of expensive materials like copper and favor aluminum and SS wherever possible. Doing so increases their price competitiveness. If a maker can cover 90+% of cooking with acceptable performance and a low price by going with straightwall SS, they'll almost always do it. And when some manufacturing genius figures out an economical, reliable way to *fully* clad thick aluminum with *very* thin SS, that'll be the next great thing.
I just looked up the tree lines of Demeyer on the Sur la Table website. The stockpots of about 8 to 9 qt. capacity are priced fro $320 to $420! I just bought a 9 1/2 qt. pot for under $100. I'd say if you want Demeyer, just get the one with the handles you like best, and not worry about heat loss.
For me, the considerations were: capacity, diameter, induction-capability, and cost.
No stockpots. I have too many to boot already.
For example, it boiled down to the 9Qt Atlantis Casserole at 11" - I chose the Viking 13" 6 Qt.
I know already how *heavy* my 4.2 Atlantis Saute is already.
Just debating about the merits and knowing the full breath I suppose, on a education cookware recap . Demeyere no Sur are disc based. SLT are fully cladded FWIW.
GH is spot on. The advantage of fully cladded cookware for a stock pot is very minimal -- if there is an advantage to begin with -- which is doubtful. For a saute pan, yes, a fully cladded cookware does help. For a casserole pot, Atlantis casserole/pot is disc bottom as you may know, while the SLT version is fully cladded. I would go for the Atlantis version if the price is not an issue. The disc bottom design for Atlantis is better.
In my opinion, there are too many variables and too small a payoff to make a scientifically valid study worth doing. My instinct, however, is that there is no value added by multiclad sidewalls in a large pot which is used mainly for mostly liquid contents. The most significant thing you can do to minimize heat loss in a stock pot is heat it with induction, in my opinion.
Have not been on a cookware *hunt* for awhile...so I was just debating the merits, the purpose, Demeyere's *philosophy* vs. the Industry 5 line, etc, etc.
Looking at a couple of things.
Plan to add the Viking Saute as I like the 13" footprint.
For volume + surface, planning to add a Sitram Prof. Rondeau or Paderno GG.
Etc, etc. Just wanted to see if anyone actually did any ~statistical~ testing
It is a difficult measurement to make because it depends on what is in the pot as well. An empty pot vs a filled pot vs a half filled pot. No, I doubt there is any meaningful measurement for it. However, the cladded sidewall definitely and absolutely do not have the surface temp on the bottom (assuming I read you post correctly).