Is Temperature the Future of Digital Vaping?

[kiwivap]

an unregulated ego puts out 4.2 at first and do to voltage drop under load it hovers around 3.7-3.9 volts

regulated ego batteries can put out 3.3 or 3.7 volts with no drop under load... depending on what ego battery you buy it will be 3.3 or 3.7

Things have changed then. Standard egos were always 3.3-3.4 volts - a cooler vape than other regulated batts. We used to advise new members on that all the time before the twists hit the vaping world. Yes, I think they drop down quickly from 4.2 straight off the charger. The regulated ones are 3.7 volts as I understand. But anyway...
Great video. If we go with 3.7 v and 1.8 ohms - 7.605 watts - around 20C. Which is even more interesting because its more power and so should be a warm vape. 20C is not cold. Least not where I live. Breathing in a 20C gas - doesn't strike me as unusual.

 

[rurwin]

10°C would be .397 mV

in my test it hung out around .7 mV with a peak of .9 mV
or around 20°C

37C

Ambient temperature is about 20C. At ambient temperature the thermocouple reads zero millivolts, because both hot and cold junctions are at the same temperature. The cold junction is where the meter connects to the thermocouple wires. The difference in temperature between the two junctions is what develops the voltage and is what you are measuring.

However it is not quite that easy, because you have to convert the cold junction temperature to a voltage and then add that to the measured voltage and convert back. It doesn't work if you do it any other way.

I assume that your room temperature is around 20C, (most rooms are,) which would be 0.79mV. You measured 0.7mV. Adding those together makes 1.49mV, which we convert back on the chart to read 37C

 

[kiwivap]

37C

That seems high for a 7.6 watt vape. 37C is very warm.

 

[happydave]

37C

Ambient temperature is about 20C. At ambient temperature the thermocouple reads zero millivolts, because both hot and cold junctions are at the same temperature. The cold junction is where the meter connects to the thermocouple wires. The difference in temperature between the two junctions is what develops the voltage and is what you are measuring.

However it is not quite that easy, because you have to convert the cold junction temperature to a voltage and then add that to the measured voltage and convert back. It doesn't work if you do it any other way.

I assume that your room temperature is around 20C, (most rooms are,) which would be 0.79mV. You measured 0.7mV. Adding those together makes 1.49mV, which we convert back on the chart to read 37C

aww yes that makes sense i am in a temp controlled room right now at 69°F

 

[kiwivap]

aww yes that makes sense i am in a temp controlled room right now at 69°F

37C? From an ego? I'm astounded. Seriously.

 

[happydave]

37C? From an ego? I'm astounded. Seriously.

kanthal starts to glow at just over 400°C. with out e-liquid and airflow that ego will make that kanthal glow very bright.

 

[rurwin]

It sounds about right to me. It's a dripper with an extended air hole, and 37C is about the temperature of a warm bath, or the human body. And it's only 17C above ambient.

 

[Ryedan]

Here's what Mad Scientist did as while back on 'Temp / Time curve inside an atomizer'. Interesting experiment

IMO you don't have to get inside the wick. Close enough and radiation & convection would probably get you good enough coil temp data to be able to drive a PV from. There would certainly be delay between wire temp change and sensor reading change, but that's part of 'the devil is in the details thing'. Microprocessors are also amazing tools and can be programmed in almost unlimited ways.

Now, I'm not thinking this is going to be quite that easy. Just thought I would toss this thought out there, for whatever it's worth.

 

[kiwivap]

kanthal starts to glow at just over 400°C. with out e-liquid and airflow that ego will make that kanthal glow very bright.

Sure, but if you step into a 37C controlled room the first two things that you notice are the heat, and that you are breathing in hotter air. Its quite noticeable.

So what I'm getting at here is 37C is quite a warm temp. I have vaped at 7-8 watts - vaping at 7 now actually - and its not near a 37C temp going into my lungs.

Which makes me think that getting the temp of the vapor is difficult - partly because it cools depending on the chamber its in. That's the whole bottom vs top coil argument that people have. Although I can't see a problem with bottom coils and prefer them - just turn up the watts. Or build a coil.

Anyway - hope you get my drift here. I love how you do these vids. Look forward to the vv one. Will be very interested to see volts correlated with temps from that.

 

[kiwivap]

It sounds about right to me. It's a dripper with an extended air hole, and 37C is about the temperature of a warm bath, or the human body. And it's only 17C above ambient.

Yes, 37C is core body temp. Trust me, that's actually quite warm. Imagine a 37C day - its pretty hot. I think that is what he measured, but I think the vapor must cool.

 

[happydave]

Sure, but if you step into a 37C controlled room the first two things that you notice are the heat, and that you are breathing in hotter air. Its quite noticeable.

So what I'm getting at here is 37C is quite a warm temp. I have vaped at 7-8 watts - vaping at 7 now actually - and its not near a 37C temp going into my lungs.

Which makes me think that getting the temp of the vapor is difficult - partly because it cools depending on the chamber its in. That's the whole bottom vs top coil argument that people have. Although I can't see a problem with bottom coils and prefer them - just turn up the watts. Or build a coil.

Anyway - hope you get my drift here. I love how you do these vids. Look forward to the vv one. Will be very interested to see volts correlated with temps from that.

we smoked cigs, i bet the temp of the smoke coming out of the filter is much hotter than the vape.

 

[kiwivap]

we smoked cigs, i bet the temp of the smoke coming out of the filter is much hotter than the vape.

It got hot near the end as I recall - cooler to start with. Its hard to remember exactly now - been quite a while. I don't doubt there are some very warm vapes - some people are vaping at high watts. But from an ego, which at best is giving 3.7 v with a 1.8 ohm coil -I think the vapor cools.

 

[happydave]

It got hot near the end as I recall - cooler to start with. Its hard to remember exactly now - been quite a while. I don't doubt there are some very warm vapes - some people are vaping at high watts. But from an ego, which at best is giving 3.7 v with a 1.8 ohm coil -I think the vapor cools.

oh for sure, the vapor cools down a lot as it makes its exit.

here is the VV mod and tank test

 

[kiwivap]

oh for sure, the vapor cools down a lot as it makes it exit.

Will watch that - while you were doing that I was reading this study which measured cigarette smoke temps.
Basically, temp depended on .... length (we know this ), - the range is what interests me. Non-filter starting in at 37C or so. Filters higher and seemed to average at 60C.

Now onto the video....

 

[rurwin]

Yes, 37C is core body temp. Trust me, that's actually quite warm. Imagine a 37C day - its pretty hot. I think that is what he measured, but I think the vapor must cool.

I've worked in a 60C oven. That was rather warm. I've burned my lip with smoke too, so that got hotter. happydave said that the ambient air temperature was 69F = 20.5C

I said earlier that you have to add voltages, not just temperatures, because I'm used to working with engines where the stuff I'm measuring is at least 100C. At those temperatures the thermocouple response is a curve so you have to do things right. However with this test everything is close enough in temperature to make it approximately a straight line, so we don't have to be so careful. 0.7mV is around 17.5C above ambient. You might argue that with only one significant digit it could be anywhere from 16.5C to 20C depending on how the meter rounds, but it is somewhere around there.

 

[kiwivap]

. However with this test everything is close enough in temperature to make it approximately a straight line, so we don't have to be so careful. 0.7mV is around 17.5C above ambient. You might argue that with only one significant digit it could be anywhere from 16.5C to 20C depending on how the meter rounds, but it is somewhere around there.

That makes more sense to me.

You worked in a 60 degree oven. That's hot. I've been in 40C weather and though that was too much

 

[kiwivap]

Ok, The first result - 3.7 v with 2.2 ohms - 6.222 watts. Medium value 0.5mV. So around 20C which tallies with the ego result. Correct me if I'm wrong here, but taking the last result - and let say the mod put out 4.8 volts with 2.2 ohm coil - so 10.472 watts. Watching the video the meter was hovering around 1.0mV. So are we looking at around 35C? Want to read the chart right here.

I think it must be.

 

[happydave]

here is the sub-ohm test.
the 18650 was fresh off the charger right before i shot this video.

 

[happydave]

Ok, The first result - 3.7 v with 2.2 ohms - 6.222 watts. Medium value 0.5mV. So around 20C which tallies with the ego result. Correct me if I'm wrong here, but taking the last result - and let say the mod put out 4.8 volts with 2.2 ohm coil - so 10.472 watts. Watching the video the meter was hovering around 1.0mV. So are we looking at around 35C? Want to read the chart right here.

I think it must be.

what Rurwin was saying is that you need to add voltage (.798 mV) to whatever reading the meter is showing
then taking that number to the chart to convert mV to °C
i totally forgot this part until he reminded me.

 

[kiwivap]

what Rurwin was saying is that you need to add voltage (.798 mV) to whatever reading the meter is showing
then taking that number to the chart to convert mV to °C
i totally forgot this part until he reminded me.

No its ok - here's what he said:

I said earlier that you have to add voltages, not just temperatures, because I'm used to working with engines where the stuff I'm measuring is at least 100C. At those temperatures the thermocouple response is a curve so you have to do things right. However with this test everything is close enough in temperature to make it approximately a straight line, so we don't have to be so careful.

Your on a straight line here - so adding voltage can be like over-correcting.