Cooling The Coil

[ciaonzo 5,000+ posts]

im pretty sure that the air being pushed by the fan would have less pressure than what your sub could produce so it really wouldnt do much, it might actually hurt more than help.

That's logical thinking for sure, but the fact that the air being moved across the coil is inside the shroud would negate that effect. Assuming the shroud is built well and it's air-tight, it would be a completely different "environment" than the inside of the enclosure. It wouldn't be susceptible to the rear wave from the driver.

 

[mossberg385t 10+ year member]

The whole environment, including the vehicle where the meter is going to be placed //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

you're running out of troll pellets

 

[hatedonmostly 5,000+ posts]

It will cool it. Have you not been paying attention. Cooler coil = more power handling before thermal limits and more effenciency which both could = db gains.

That wouldn't affect efficiency //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif the only way it would be more efficient is if it wasn't generating heat, and since it truly is generating heat and you're only attempting to cool it, it would still be as inefficient. That's like using painkillers to mask the pain of a broken leg and saying you didn't hurt yourself.

If it hurt people wouldnt do it.. i have seen it done but mostly by hardcores...

You've seen people run A/C into a box. That would cool the entire box, as apposed to putting a small fan inside the box and using that to cool just a component of the sub.

 

[hatedonmostly 5,000+ posts]

you're running out of troll pellets

I lol'd.

 

[350regal 10+ year member]

That's logical thinking for sure, but the fact that the air being moved across the coil is inside the shroud would negate that effect. Assuming the shroud is built well and it's air-tight, it would be a completely different "environment" than the inside of the enclosure. It wouldn't be susceptible to the rear wave from the driver.

yea with a good airtight shroud it would work but he didnt mention that. he just asked about a fan in the box not about sealing the motor.

 

[ciaonzo 5,000+ posts]

yea with a good airtight shroud it would work but he didnt mention that. he just asked about a fan in the box not about sealing the motor.

Indeed. I was referring more to what I suggested. //content.invisioncic.com/y282845/emoticons/thumbsupwink.gif.129404938effda6ad9cca39e7f4b58a3.gif

 

[ciaonzo 5,000+ posts]

I'm trying to remember what company it was that used this approach. It was a huge servo-driven subwoofer with two 15" cones in a face-to-face configuration which was used for outdoor venues. Anyway, the DC servo motor was huge and created gobs of heat so they had to fan cool it so it didn't die during the concerts.

 

[*SlappinAzz*]

No reason to get upset bro, I personally think it's a stupid idea but I suppose you could try it, you'd probably be the first lulz.

Its a smart idea actually...

 

[350regal 10+ year member]

I'm trying to remember what company it was that used this approach. It was a huge servo-driven subwoofer with two 15" cones in a face-to-face configuration which was used for outdoor venues. Anyway, the DC servo motor was huge and created gobs of heat so they had to fan cool it so it didn't die during the concerts.

yea i remember that but no idea on what the company was, it was a huge isobaric servo set up with blower fans on the motors right?

 

[ciaonzo 5,000+ posts]

yea i remember that but no idea on what the company was, it was a huge isobaric servo set up with blower fans on the motors right?

Yep, that's the one. I know the early versions didn't have the cooling setup but they implemented it after they were having failures in the field. I remember the hoses looked the ones on my vacuum cleaner.

 

[ahole-ic]

Here is what is on the table. We know that natural convection does not cool things quickly enough. The hot air pools around the device and slowly rises away from it. Coils are not efficient at convection cooling like a heatsink would be. A fan blowing creates positive pressure. Anything in the path of the airflow creates eddies or pools of air that do not move, and it also redirects the air that does. A fan blows and sucks at the same time. If you utilize the negative pressure or suction, you MUST use a shroud, but by doing this you direct the airflow. The pools of stagnant air are no longer an issue because they can't redirect air.

What does any of that mean? It means just blowing a fan on the voice coil without careful planning will probably not help by any measurable amount. It CAN actually hurt if the cooling that the sub designers built in is obstructed by the airflow you've forced into its environment.

In my opinion, formers built out of high thermally conductive ceramics should be utilized and flat-wound coils could have their shellac sanded away on the side to come into contact with the former (as it is an electrical insulator) Then the ceramic naturally turns into a heat spreader, and inside of it, could be heat pipes. (Hollow channels that contain fluids that evaporate at low temps.)

Then make the dustcaps a lightweight aluminum heatsink. I don't know how much moving mass this would add. It would certainly add to production costs, but it SHOULD up the thermal power handling limits considerably.

Don't forget, the subwoofer moves on its own so the coil is already moving through air. I realize that this air stays basically stagnant and the same heat gets re-introduced to the voice coil, but the fan WILL NOT necessarily break this stagnant air up. It could actually CREATE more stagnant air. It's a great idea, but it will probably fail in implementation.

 

[*SlappinAzz*]

I just crank the AC on Cold to keep the air freezing inside the car.

 

[k_schutte 10+ year member]

Whats the flash point of NOS and how hot does the surface of the coil get. Not to mention a steady flow of electricity could easily equal and explosion.

hows that? Nitrous is not flammable...

 

[CRXBMPN 5,000+ posts]

put your hand in front of the port at or near full tilt, tell me how a little fan blowing onto a coil/motor is going to actually keep that air going in that direction when you have massive amounts of air going all over hell and creation in the box... I see it impossible to concentrate that airflow into the area you want it to. I will however say that I try and keep my subs/amps as cool as possible before a burp or whatever, because cooler coils = less imp rise, yes? I think you have a great idea but in theory it wont work. Try and blow air out of your mouth and concentrate it onto something while you are standing in the middle of a hurricane, I just dont see it working.

 

[CRXBMPN 5,000+ posts]

plus, you want to mimimize the ampreage taken away from the amp, so adding an electrical device will use a bit of energy, albeit not much, but hey... voltage = smiles //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif