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Rocket Scientist Designs "Flare" Pot That Cooks Food 40% Faster
An anonymous reader writes Oxford University engineering professor Dr Thomas Povey just invented a new cooking pot that heats food 40% faster. The pot is made from cast aluminum, and it features fins that direct flames across the bottom and up the sides, capturing energy that would otherwise be wasted. The pot is set to hit the market next month in the UK. "Povey specializes in the design of high-efficiency cooling systems for next-generation jet engines. He is also an avid mountaineer and says that this invention was spurred by the long time it takes for water to reach a boil at high altitudes. He and a group of his students worked three years experimenting with different designs before they came up with one being marketed."
The pictures show it to be quite different.
much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
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Not to mention that as a mountaineer, I'd think he'd care more about cooking efficiency than cook time. And while it's great to utilize the flame energy more efficiently, there's a far more significant optimization one can do - make insulated cozies that fit your pots. Bring to a boil, shut off the heat, put the pot it in the cozy and let it cook. For my pots, I made an underpiece and a lid that fits over each other, both out of aluminized foam; it works very well.
(Of course, he could be one of those people that doesn't eat any "cooked" meals, only the "just add boiling water" meals. In that case, then I guess it's all about the efficiency of using the energy from the flame
What I want to see in backpacking is a full integrated system. Where the tent is a hammock is a backpack is a ground cloth is a pack cover is a camp chair and so on down the line, where most components serve multiple uses. When I think about how much "fabric" and "rigid structures" I carry with me that if designed properly could be eliminated, it just seems like a waste.
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A liquid boils when it reaches the temperature at which the partial pressure of its vapor equals the external pressure. Higher altitude means lower external pressure which means water boils at a lower temperature at high altitude which means a pot of water boils faster, but food cooks more slowly.
No, I don't believe it boils faster. Granted, as you correctly explain, it takes less energy to boil water at high altitude, but there's other factors you're leaving out, for instance, the big one I know about: efficiency of combustion. So while it takes less energy to boil that water, guess what you're getting from your stove? A lot less energy...
I use a couple of inch (5 cm) high ring of aluminum foil, shiny side in, around the burner. That reflects heat from the burner and the pot itself back onto the pot, and reduces convection losses by partly blocking air coming in around the edges. Obviously if you are using gas burners, you need enough air for the flame. A strip of foil is going to be way way cheaper than an $85 pot.
When choosing pots, pick one that is black, not shiny, or make it black by burning stuff on the outside. Black surfaces absorb heat better.
So, what this pan does is actually very simple; the fins on the sides provide more surface area to catch the heat that slides up the side by convection forces when the pan sits on a gas burner. The "gas burner" part is incredibly important, as if you have an electric burner there will be negligible benefit, and maybe even a negative result. That extra surface area can bleed heat as well as it collects it. And since the pans are cast aluminum, if you have an induction cooktop they won't work at all.
So, let's say you have a gas burner, and one of these pans. Here's what I see as a potential issue. The walls of this pan will get hotter than they do when you use another more traditional type of pan. And that's not necessarily a problem, as long as you keep stirring. But that extra heat will tend to cause liquid at the edge/top of the contents of the pan (the meniscus) to heat far more aggressively. Which means that you will likely get a degree of crusting, scorching, etc...depending on what's in the pan, of course. Water? No problem, it's water. But if you're cooking a sauce, or making something like boxed risotto (not the real hardcore risotto, which requires constant stirring and so would not scorch) or some other grain, you may have some issues. They have a stockpot, which at first would seem like the ideal situation...except that if you're doing most things you would do with a classical stockpot (like making a large batch of stock or soup or stew) you may have MAJOR issues with that scorching.
I have to say...I have a gas cooktop, I cook a lot, I cook elaborately, we have a gas dryer, we have gas-fired heat in the winter. It's a decent-sized single family home. And my gas bill doesn't get high at all...average is a bit less than $50/month. I find it hard to imagine that these pots would make much of a difference in my gas consumption at all. Maybe if my cooktop were really wimpy, the speed of cooking would be nice...but isn't the better option just to get a better cooktop in that case? These pans don't help if you're using a skillet, or the oven (which would also probably be weak if the top burners of the stove are weak), and they cost quite a lot. It'd be cheaper to just upgrade the cooktop than replace all of your pans with this, and the results will be more controllable. I'd love a big pot to boil water for pasta that worked like this...but for every other application it seems to me that upgrading the range would be a better way to go.
But hey, that's just my two cents.
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When I was in the military and trying to cook frozen food over a camp stove in the Arctic we used pressure cookers. It is fast and heated the food completely without burning the bottom. It is also the most energy-efficient method of cooking Now if they added the flare design to a pressure cooker they might have the best of both designs.
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Well, field trials revealed that he was too good and raised the temperature to nearly the melting point of aluminium! The flue gases and soot abraded the bottom of the pots and they started leaking in just a few sessions. The older inefficient method wasted firewood, but the pots lasted longer.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I'm not much of an aluminum fan for cookware. Since its made via casting, how about an iron one?
Suppose you were an idiot. And suppose you were a member of congress. But then I repeat myself. -- Mark Twain
Or I guess he never heard of or used MSR equipment, eh? Y'know, 'cuz it's only been around, like, thirty-five years or so.
This is a good opportunity to quote this famous faxlore.. Heaven is where the police are British, the lovers French, the mechanics German, the chefs Italian, and it is all organized by the Swiss. Hell is where the police are German, the lovers Swiss, the mechanics French, the chefs British, and it is all organized by the Italians.
I'd hardly call the Flare pot a breakthrough, although it is a very smart design.
Corrugated, punctated, ungulated, and other stressed-surface cooking pots have been around for thousands of years for this exact reason. The Guarani of Brazil basically perfected the technique in their incredibly efficient cooking pots--this was the topic of my Fulbright archaeological research in 2008-2009.
In ceramics, a corrugated finish not only takes better advantage of the fire, but also prevents thermal stress fractures, so long as an appropriate temper has also been added to the clay. Archaeologist James M. Skibo has been studying the profound efficiency of indigenous cookware since the '80s. Where once archaeologists though of cookware as "crudware", it is now generally viewed as a technological feat of immense importance and skill.
The pictures don't show the inside. If the inside bottom is as tortuous as the outside, the cleaning is gonna be a real challenge indeed.
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Jetboil is great for camping - not so great for everyday stovetop use - the exchanger is way too delicate and the insulation jacket is impractical for a set of pots and pans. MSR Reactor is similar (I prefer it - no jacket - if my MSR Rocket ever fails it'll be next), and I expect a lot of the benefit from both comes from a much better windscreen - and that includes the Jetboil accordion that helps channel the heat. The biggest issue with any camp stove that perches a pot above a burner is the relatively giant wind-whipped space between them. You learn to practice a delicate dance of non-flammable objects upwind of your stove - chef included - with most others. The trusty old suitcase Coleman stoves are still revered for having this built into the design, but for backpacking they're an albatross. Jetboils are also only for boiling water - cooking in them can cause the aluminum exchanger to fail, as they depend on the constant flow of heat into the water - this has been an issue with Jetboils, though predominantly with the Ti version.
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JetBoil has a lot of pieces that can become damaged and compromise the efficiency of the product. This one is a single, solid piece that just functions by having a much larger surface area due to the rippled surface of the pan, thereby allowing it to contact more of the heat source than a conventional, single solid piece pan. This pan would appear easier to clean by far, and more difficult to damage.
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http://patentscope.wipo.int/se...
the patent seems to talk in terms of surfaces for heat transfer, and does not mention anything about turbulence. When he first mentioned to me that he was working on it, I conjectured that it was vanes or ribs of some kind, and he told me that it was more complicated than that and had to do with the interaction with turbulence (I forget whether to increase it or decrease it). However, nothing like that seems to be reflected in the patent. I'll ask him to respond here on Slashdot if he can.
The
Chefs prefer gas over electric stoves because it heats the cookwares fast, directly - not indirectly through a cooking plate that has to get warm first and stays warm afterwards.
Induction stoves are just as fast as gas burners, and has better thermal efficiency, plus being safer.
The drawback is that the cookware has to be of iron and have a flat bottom. Cast-iron pots and pans used to be very heavy, but there is cookware today where the iron layer is sandwiched with ceramic or aluminium which are much lighter. You can't use a round-bottomed wok, though.
"We mustn't be caught by surprise by our own advancing technology" -- Aldous Huxley
I don't want BTUs in my food, I use metric, so it has to be Joules.
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Where do you live that they ban gas-flame cooking?
It is a solid piece, and is dishwasher safe. How would the cleaning of it be any different than a ridged pie tin, a soufflé pan or a cupcake pan?
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Or very, very right.
I hate printers.
A pressure cooker cooks faster by boiling slower. If water boils at 90C instead of 100C, (say 190F instead of 212F) it boils faster, but keeps whatever you're trying to cook at a lower temperature, and because of that, the cooking time lengthens. This is an issue at high altitudes where air pressure is low, say 700 mmHg instead of 760 mmHg (or 12 psi instead of 14 psi at sea level) and the boiling bubbling equalizing pressure is reached at 90C instead of 100C at sea level. A pressure cooker is like taking a pot up high on the mountain, and carrying it deeper to sea level, or even below: it increases the boiling temperature by increasing the pressure inside the pot. The end result is 110C (230 F) boiling water, and in the higher temperature everything cooks faster, including eggs, pasta, veggies, etc. That is how a pressure cooker is more efficient in cooking, not by better heat transfer, but by creating a higher temperature, faster cooking environment inside itself. That's a lot of energy savings. However, ever since the Boston marathon bombing manhunt, the authorities don't like people buying pressure cookers.
Wouldn't a standard pressure cooker set to sea level pressure solve this problem?
Pressure cookers help, a lot. But they're not "set to sea level pressure", they are set to a differential pressure of whatever the current pressure is + some fixed PSI. (Or, in the case of the one I use at home, your choice of 2 pressure offsets.) So you need either experience or some mental juggling to estimate cooking times with one.
So, yes, depending on your altitude, they can help a lot, or make it just like cooking at sea level, or make it faster. And they do make lightweight portable ones for camping. But "lightweight" and "portable" are relative. You would NOT schlep one of these along for a solo backpack trip. But if you have any kind of vehicle, or porters, supporting a more heavily-equipped trip, then it's certainly an option.
Likely because they ain't cooks. The pot works well if the pot is full, if not it burns food up the sides of the pot, especially those bits you leave behind when stirring. The pot has far more surface area to clean. The pot only work with gas. The catch is for those who cook you really only want your heat at the bottom of the pot and not so much at the sides, in fact optimum pot design is insulated sides and a very conductive base. Even the base tends to be better for cooking a thick cast iron in order to balance out the vagaries of thermostats. Yep he is definitely a rocket scientist and not a cook.
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Nope:
http://home.howstuffworks.com/...
The clear winner in the energy efficiency battle between gas and electric is gas. It takes about three times as much energy to produce and deliver electricity to your stove. According to the California Energy Commission, a gas stove will cost you less than half as much to operate (provided that you have an electronic ignition--not a pilot light).