Wire cooling down?

[Renoster]

Good day... i was just wondering, what type of wire cools down the quickest? As i think obviously wires that stays hotter for longer after you vaped still sucks up your juice... I know i can google it, but i find the advice here alot more accurate and true than mr.google! And the poeple here are great!!

 

[blujeenz]

Good day... i was just wondering, what type of wire cools down the quickest? As i think obviously wires that stays hotter for longer after you vaped still sucks up your juice... I know i can google it, but i find the advice here alot more accurate and true than mr.google! And the poeple here are great!!

Let me be the first poeple to say I think its titanium.
SS is def longer and even the thinnest kanthal clapton(26*32) is longer than both, dunno about Ni though.

 

[KZOR]

I found the following post helpful when I wondered the same thing awhile back.

https://mrlongdrag.com/2015/11/02/4-types-of-wires-used-for-vaping/

 

[Atsbitscrisp]

This is a fairly complex issue if you wanna dive down into the theory of material science. The shortest answer I can give you is the thinner the wire, the quicker it will cool down. A single strand of thin wire in a spaced coil will cool the quickest. A thick and complex coil like a staple coil or multicore clapton with no spacing on wraps will take a lot longer to cool. Clean coils will cool quicker than gunked coils. Get your technique right.

In terms of material, a general rule that could be followed is "the lower the specific resistivity, the faster the thermal conduction." This means that lower resistance wires will be able to cool down quicker. The problem with this is that we build to a specific resistance so we end up using more material by wrapping more loops. This means that even though the coil dissapates heat faster, the pool of heat it needs to dissipate will tend to be larger. This needs to be calculated using the integral heat capacity equations for the specific type of wire being used. If I had to hazard a guess, I would choose kanthal for the best blend of resistivity vs thermal conduction and heat capacity. However, it is practically insignificant so no need to be worried about this on such a small scale. EDIT: changed my mind, titanium ftw!

One must also consider the gauge of the wire being used. As the diameter of the wire decreases, we have a change in the specific surface area to volume ratio. This has a great impact on the heat transfer. The smaller diameter wire will be able to get rid of the heat alot faster than a thick wire. These equations are further complicated by complex coils which have many different interacting surfaces. This also affects how spaced vs close packed coils hold heat. Spaced coils have a greater area exposed to the cooler surroundings. The metal-metal interactions and the increase heat density of the contact coils means they will tend to cool down slower.

The issue of coils getting gunked will also have an effect on the cooling of a coil. The buildup can act as an insulator which will cause the coil to hold heat a lot longer as heat from the core is not allowed to dissipate fast enough to surroundings. Heat may also be absorbed in this layer meaning your coil will heat up slower, have more heat capacity as well as cool slower. EDIT: This effect may also be possible with metal oxide buildup. Toss the rusty ones, its only wire...

Wicking and vaping techniques can also affect the cooling of your coils tremendously. Thick wicks with lots of cotton-coil contact allows for greater transfer of heat to the juice and wick. Conduction has the ability to transfer heat better than convection so the greater this contact, the more conduction can occur cooling the coils quicker. Convection will also play a role in the cooling of coils. This is influenced by the type, style and technique of the draw. DTL will give greater airflow over coils causing them to cool quicker. Airflow directed at the coil allows it to cool quicker vs non direct airflow to coil. In terms of technique, the moment of power release will also influence the final temperature of the coil after a draw has been taken. I tend to draw on the device for a further 0.5s after releasing power button just to counteract this effect.

Uhmmm.... thats about all I have for now, if anyone else can chime in, it would be helpful. #sciencemuststayexactlyhowitisbecauseitrocks. #dontknowwhyiamusinghashtags #these#seriouslyirritateme #ishouldstopdoingthis #youshouldstopreadingthis #infiniteloophelp!!!

 

[Silver]

Wow @Atsbitscrisp , that was awesome!
Thanks
Very interesting and insightful!

 

[Renoster]

This is a fairly complex issue if you wanna dive down into the theory of material science. The shortest answer I can give you is the thinner the wire, the quicker it will cool down. A single strand of thin wire in a spaced coil will cool the quickest. A thick and complex coil like a staple coil or multicore clapton with no spacing on wraps will take a lot longer to cool. Clean coils will cool quicker than gunked coils. Get your technique right.

In terms of material, a general rule that could be followed is "the lower the specific resistivity, the faster the thermal conduction." This means that lower resistance wires will be able to cool down quicker. The problem with this is that we build to a specific resistance so we end up using more material by wrapping more loops. This means that even though the coil dissapates heat faster, the pool of heat it needs to dissipate will tend to be larger. This needs to be calculated using the integral heat capacity equations for the specific type of wire being used. If I had to hazard a guess, I would choose kanthal for the best blend of resistivity vs thermal conduction and heat capacity. However, it is practically insignificant so no need to be worried about this on such a small scale. EDIT: changed my mind, titanium ftw!

One must also consider the gauge of the wire being used. As the diameter of the wire decreases, we have a change in the specific surface area to volume ratio. This has a great impact on the heat transfer. The smaller diameter wire will be able to get rid of the heat alot faster than a thick wire. These equations are further complicated by complex coils which have many different interacting surfaces. This also affects how spaced vs close packed coils hold heat. Spaced coils have a greater area exposed to the cooler surroundings. The metal-metal interactions and the increase heat density of the contact coils means they will tend to cool down slower.

The issue of coils getting gunked will also have an effect on the cooling of a coil. The buildup can act as an insulator which will cause the coil to hold heat a lot longer as heat from the core is not allowed to dissipate fast enough to surroundings. Heat may also be absorbed in this layer meaning your coil will heat up slower, have more heat capacity as well as cool slower. EDIT: This effect may also be possible with metal oxide buildup. Toss the rusty ones, its only wire...

Wicking and vaping techniques can also affect the cooling of your coils tremendously. Thick wicks with lots of cotton-coil contact allows for greater transfer of heat to the juice and wick. Conduction has the ability to transfer heat better than convection so the greater this contact, the more conduction can occur cooling the coils quicker. Convection will also play a role in the cooling of coils. This is influenced by the type, style and technique of the draw. DTL will give greater airflow over coils causing them to cool quicker. Airflow directed at the coil allows it to cool quicker vs non direct airflow to coil. In terms of technique, the moment of power release will also influence the final temperature of the coil after a draw has been taken. I tend to draw on the device for a further 0.5s after releasing power button just to counteract this effect.

Uhmmm.... thats about all I have for now, if anyone else can chime in, it would be helpful.

Thanx for the detailed reply!