Induction heating
Induction heating
I've seen the hype on TV about boiling water in "seconds" with these induction hotplates. Interesting but I assume special pots are needed to make them work.
John Buck
Brother John's Brewing
The Monk at the Hartley Monastary
Brother John's Brewing
The Monk at the Hartley Monastary
Induction heating
Yes, you need a layer of magnetic metal in the bottom of the pot.
I've thought about building a big coil, and dropping a cast-iron plate (or a block of magnetic stainless) in a kettle. Never gone anywhere with the idea, though.
-Jim
Post generated using Mail2Forum (http://www.mail2forum.com)
I've thought about building a big coil, and dropping a cast-iron plate (or a block of magnetic stainless) in a kettle. Never gone anywhere with the idea, though.
-Jim
Post generated using Mail2Forum (http://www.mail2forum.com)
Induction heating
I've got a small induction plate that I use sometimes, but I've only got a couple pans that work with it. I just haven't had the time to look into how to build a big plate. I saw them make one on Mythbusters for making a huge amount of popcorn.
On Mon, Jun 25, 2012 at 12:05 PM, jjbuck <brew-equipment@crbeernuts.org (brew-equipment@crbeernuts.org)> wrote:
On Mon, Jun 25, 2012 at 12:05 PM, jjbuck <brew-equipment@crbeernuts.org (brew-equipment@crbeernuts.org)> wrote:
Post generated using Mail2Forum (http://www.mail2forum.com)Is the cost prohibitive?
Induction heating is just another means of energy transfer. By coupling electrical energy into the pot and directly generating heat in the body of the cooking vessel, it eliminates a thermal choke point and lowers the thermal energy transfer time constant. If you were trying to boil a cup of water, you would undoubtedly notice the pot heat up faster relative to a coil-based or flat-top electric stove. If, however, you were trying to boil 10 gallons of water, I doubt you'd see a difference, since the driving factor in that case would be the thermal mass of the water and the power level of the heating element.
From talking to a few guys at work about the topic, it's my understanding that the energy transfer mechanism in an induction heater is a combination of skin effect ohmic loss and bulk magnetic losses. If the cooker is designed to only couple energy into a ferrous plate, then you'll need to use something like a cast iron pot. That being said, if you were to design your own induction heater, you shouldn't need a pot made from a magnetically lossy material or a similar substrate with a good thermal path to your kettle. In a higher frequency induction heater, where the pot acts like a single turn loop on the secondary side of a transformer, the electric currents running through the pot will dissipate and create thermal energy in the walls of the pot. As long as it isn't a super-conductor, almost any metal will create heat nicely.
The first video, below, shows an example of melting an iron bolt (i.e. a ferrous material) with a home-made induction heater. The second video is similar, but they melt an aluminum can (i.e. a non-ferrous material). I suspect that you could build an induction heating loop to go around a stainless keg, but be prepared for an adventure. At a minimum, I would guess you'd need to set up a water cooler to dissipate the several hundred watts of heat coming from the coils, since the energy transfer probably won't be more than 90% efficient.
http://www.youtube.com/watch?v=CyG0Ri0dqI4
http://www.youtube.com/watch?v=d7DBS2Is ... ure=fvwrel
http://www.mindchallenger.com/inductionheater/
From talking to a few guys at work about the topic, it's my understanding that the energy transfer mechanism in an induction heater is a combination of skin effect ohmic loss and bulk magnetic losses. If the cooker is designed to only couple energy into a ferrous plate, then you'll need to use something like a cast iron pot. That being said, if you were to design your own induction heater, you shouldn't need a pot made from a magnetically lossy material or a similar substrate with a good thermal path to your kettle. In a higher frequency induction heater, where the pot acts like a single turn loop on the secondary side of a transformer, the electric currents running through the pot will dissipate and create thermal energy in the walls of the pot. As long as it isn't a super-conductor, almost any metal will create heat nicely.
The first video, below, shows an example of melting an iron bolt (i.e. a ferrous material) with a home-made induction heater. The second video is similar, but they melt an aluminum can (i.e. a non-ferrous material). I suspect that you could build an induction heating loop to go around a stainless keg, but be prepared for an adventure. At a minimum, I would guess you'd need to set up a water cooler to dissipate the several hundred watts of heat coming from the coils, since the energy transfer probably won't be more than 90% efficient.
http://www.youtube.com/watch?v=CyG0Ri0dqI4
http://www.youtube.com/watch?v=d7DBS2Is ... ure=fvwrel
http://www.mindchallenger.com/inductionheater/