Creating an Air Flow Meter Using an Iron Heating Element

AI Thread Summary
The discussion revolves around creating an air flow meter using a heating element from an iron, with plans to measure air flow based on changes in current as the element cools. Concerns are raised about the accuracy of measuring resistance changes due to self-heating and the potential dangers of overheating the element when powered at 12 volts. Suggestions include using thermometers to measure temperature differences upstream and downstream for better accuracy. The user aims to convert the current to voltage for microcontroller integration. Overall, the feasibility of the proposed method and safety considerations are central to the discussion.
RApak
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Homework Statement



i am trying to make an air flow meter using an heating element which i got from an iron..basically i have thought of inserting the element into a duct through which i will pass air using a blower,to connect the element with a 12v supply in series with a ammeter...thn i ahve planned to scale the amount of air flowing with respect to the cahnges in current tht it produces.i am not sure if i will suceed with this idea..i would like to know what others tink about it

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The Attempt at a Solution

 
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You mean to measure the changes in resistance due to self heating? I don't think that will be very accurate. I'd think you'll need an upstream and a downstream thermometer.

I hope this is an 110V heating element, that you run with such a low voltage that the temparature can't get dangerously high? Even at only 1% a heating element without attached iron can get quite hot already.
 
i just want to measure the air flow using the element..if i apply 12 volts across it and let air flow across it it would cool down and the resistance would change causing the current to change right??..i have to further convert the current to voltage so that i can use a micro controller ahead..if u have any other ideas of how to make an air flow meter please do post them
 
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