Project help please, Heating element

[hemant]

Hi

my son is trying to make a heating element for his project

needs to use a small battery idealy rechargeable AAA to heat a ceramic, glass or copper plate

the device has to be portable so all components have to be small as possible

tempreature has to be regulated either by a thermostat, dial or switch between 180

 

[revjames]

Cant imagine an AAA battery providing enough current to heat something up to 200C

 

[steptoe]

it is actually very easy,

but as I am rubbish on computers it will be easier for a more intelligent lifeform to post you a drawing than me try to explain to you.

are you sure you are not trying to make an incendiary device by the way.?

---------- Post Auto-Merged at 22:56 ---------- Previous post was made at 22:55 ----------

Cant imagine an AAA battery providing enough current to heat something up to 200C

rev, a watch battery would do the job very easily.

 

[hemant]

He is trying to create a portable device that someone can do experiments in the feild, the intention is to heat samples in a glass test tube or ceramic bowl with a liquid. you can either wrap a coil around the test tube or create a cooper plate which wraps the test tube thats why he needs to be able to control the temp accurately.

 

[Riggy]

rev, a watch battery would do the job very easily.

Do you really believe a watch battery can hold enough energy to heat even a very small amount of liquid to 180 degrees?

 

[steptoe]

Do you really believe a watch battery can hold enough energy to heat even a very small amount of liquid to 180 degrees?

I dont know,

but I do know a watch battery will generate enough heat to ignite a disposable lighter if utilised in the correct manner.

it can also be used in a similar manner to ignite cotton wool embalmed in a mixture of "alcohol" and sugar to the correct proportions.

my point was that if a watch battery could do it then a AAA should deffo have the capabilities/power to do so, it would be the amount of repetitions that would be the limiting factor.

in all honesty I dont think a watch battery would ever come close to doing it more than once, and even then it can sometimes be temperamental.

 

[Riggy]

I dont know,but I do know a watch battery will generate enough heat to ignite a disposable lighter if utilised in the correct manner.

it can also be used in a similar manner to ignite cotton wool embalmed in a mixture of "alcohol" and sugar to the correct proportions.

my point was that if a watch battery could do it then a AAA should deffo have the capabilities/power to do so, it would be the amount of repetitions that would be the limiting factor.

in all honesty I dont think a watch battery would ever come close to doing it more than once, and even then it can sometimes be temperamental.

Your knowledge of incendiary devices using small batteries is frightening (but may be saleable in the right market!)

 

[Sidewinder]

Riggy,

Do you know where Steptoe hails from? :^O ; \

 

[hemant]

Do you really believe a watch battery can hold enough energy to heat even a very small amount of liquid to 180 degrees?

I never once said it was a watch battery. AAA battery is the small long tubular battery which is used for toys, flash lights, remote controls etc surely that can be used

if you dont want to help dont. stop side tracking my question please i need help with what i am trying to do not debate what my intentions are

---------- Post Auto-Merged at 21:48 ---------- Previous post was made at 21:44 ----------

i also never said i want an incendiary, do you think i have time to make stupid things like that, are you trying to wind me up, it is not appreciated. i thought i was joining a serious forum

 

[Sidewinder]

hemant,

You have joined a serious forum, it's just we try to have a laugh while we are here.

You may not think that anything has been gained from the previous posts, I think you are wrong!

You mentioned an AAA battery, the energy capacity of this was questioned by the Rev.

Steps came back and suggested that even a watch battery could hold enough energy to do this, but perhaps only once.

So you have had some valuable info.

Also NO ONE has accused you of attempting to make an incendiary device.

As i have just finished off my work for the day I'll try to put something helpful together for you, but you will have to give us some more information.

At what level is this project?

GCSE, A Level, ONC/D, HNC/D, 1st Degree, Masters, PhD?

The academic level will have a bearing on the complexity of the device.

First thing is you need to establish the liquids that are to be heated, then find their specific heat capacity.

You need to estimate the delta T.

You need to decide on the ambient temperature limits through which this device must operate and reach its final 180/200 Deg C

Then you will need to estimate / model the heat loss during the procedure, it is doubtful it will be adiabatic.

(See guys told you it has other uses, different form though...)

The problem you have immediately is the small volume of substance, small volume in a large container = large heat loss.

Once you have these factors you are then in a position to decide how much energy you need and in what time period.

From this you can look at the energy supply needed.

You will then need data on the AAA battery, different makers will have different capacities as will different battery technologies.

Will the same battery power the control system?

Remember a basic resistive control will dissipate energy, thus wasting your available energy reserve.



Have a think about this then come back to us.

 

[Andy™]

consider how a soldering iron works. you can get small battery powered ones.