>> 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/
http://www.zazzle.com/MathematicalOrchid*

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