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>> Interesting. On my oven, it does.
>
> It's broken then. In a cold oven, any temperature setting significantly
> above room temperature should cause the maximum size flame to be used.
> Once the oven gets to that setting the thermostat should then regulate
> the gas flow to keep that temperature.
Well, we've since thrown the old oven away. But the brand new one we've
got does exactly the same thing. And that has a mechanical thermometer
inside which shows me it's working correctly.
>> [There is some kind of sensor that detects whether the gas has
>> ignited. When you turn the oven on, it lets in a tiny amount of gas
>> and ignites it. Then, after a few seconds, the flame suddenly grows to
>> full size. Thereafter it remains at that size until you turn the oven
>> off.]
>
> That is a different system, that is there to stop the gas coming out
> full whack until the oven knows that it's actually ignited. Otherwise
> if there is a fault (and the gas is not ignited) then you might end up
> filling your house with gas, which is not such a good idea.
Uh, yah. I figured. ;-)
>> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
>
> The specific heat capacity of air is roughly 1 Joule per gram per degree
> Kelvin. So I make that about 45 kJ.
Right. I had no idea what the technical term for that is.
Now I simply *must* know if the specific heat capacity of oil is
significantly different from water... (Every time I make cheese
toasties, the cheese inside is hotter than lava! They should fill
storage heaters with that stuff or something...)
> You probably want to heat up some of the metal inside the oven too...
Oh, for sure. And I assume that there's some kind of air pathway to let
more oxygen into the oven too - and hence a similar pathway that lets
the hot air escape. I just wanted to get some idea "how big" the number is.
>> (And how much energy is released when you burn some methane...)
>
> Googling "energy density methane" seems to give 55 MJ / kg.
On the other hand, what the HELL volume of methane gas weighs 1 kg? ;-)
--
http://blog.orphi.me.uk/
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