Does this seem cool?

[Domsz06]

SP,

so I'll just turn the air over then and it should work,cool. That will save me battery juice.

But as far as the gains, I need to re read your thread on that one. I have turned my gain down, and the amp still gets very hot without a fan on it. I'll look into it all once I get all of them all lined up.

[jleger98]

so the gist of all this is, just have a fan that circulates the air in the compartment, preferrably blowing on the blades of the amps and everything should be fine.

[spharis]

Here's a formula just to help show how the differnce isn't worth the effort.

amount of heat transferred = mass x change in temperature x specific heat

I am going to assume aluminum for the heat sinks, and a mass of 100...just to make it constant. We just want to see the difference in temps. The specific heat for aluminum and air are real close, so we wont worry about them being different materials either....We will assume one large chunk of aluminum (although it is air and aluminum)
SH:
Air 1.01
Aluminum 0.902

the heat transfer is measured in Joules. calc for joule into a calorie is
4.18 J = 1 cal.

Let's assume the heat sinks are 120 degrees.
Lets assume the air is 95 degrees
Let's make the specific heat 1 (the average of the two materials).

Ok lets do some math.
heat tranfered = 100 (mass) * 25 (change in temperature) * 1
heat transferred = 2500J

Let raise the temp in the compartment to 120 and the sinks to 125
heat transferred = 100 * 5 * 1
heat transferred = 500J

difference of 2000J
thats about 500 calories

a calorie is the energy required to raise 1 gram of water 1 degree. So if you have 500grams of water, the temp would go up 1 degree.
1 ounce(weight) is 28 grams.
500/28 = 17ounces(weight) of water.

500 grams (1 pound) of water wieghs .99 pounds.

A pound of water is rougly 15.8 ounces ( I think??)

So figuring that you have 100 grams of heatsink, the difference in cooling it with the air temperature difference of 25 degress isn't enough heat energy left over to heat a bottle of water 1 degree, you can see how non-efficient the effort to add cool air vents would be.

[spharis]

SP,

so I'll just turn the air over then and it should work,cool. That will save me battery juice.

But as far as the gains, I need to re read your thread on that one. I have turned my gain down, and the amp still gets very hot without a fan on it. I'll look into it all once I get all of them all lined up.

Amps, get hot....hot to the touch, they are designed to. You should be able to hold your hand on it, albiet a little uncomfortable for a while. Your amps aren't going into protect are they?

[Domsz06]

yeah they are, that's why I put fan on it and it solved the problem and opend the compartment. I do't want to have to always open the compartment.

[spharis]

Amps are real inefficient.....about half the energy is converted to heat with them.

What kind of fans, how are they installed? You might need to add more. what amps are you running?

Another option might just be to add a passive port on top of the compartment. Just something to let the air circulate. Kind of like the old/new cooling for houses using solar chimneys.

[jleger98]

So figuring that you have 100 grams of heatsink, the difference in cooling it with the air temperature difference of 25 degress isn't enough heat energy left over to heat a bottle of water 1 degree, you can see how non-efficient the effort to add cool air vents would be.

Yeah, but getting you to spew all this hi tech stuff sure is fun

[Domsz06]

well right now it's just the PPI amp I have and I Just have one squirl cage fan, like this on it.


http://www.cardomain.com/item/STISF3N

I'm making it 6 ppi amps, one like i have, 3 1500's and then two small 180s. I think just placing air on them will be ok, then drawing the air out will be ok. The problem with the one I have now, I think is the internal cooling fan is blowing into a corner. and not really getting the air out. I'm bringing the amp out this weekend, and gonna run it in a big box, but allow it to not be in a corner to see if that still over loads it and see what happens.

[spharis]

Dom, I think in your case, you are going to need to exchange the heat outside the compartment, but for most setups (2 amps) there is really no need.

Even so, you should be able to just add a vent or 2....no forced cooling.

[spharis]

Yeah, but getting you to spew all this hi tech stuff sure is fun

Hah...well if someone wanted to get real fancy they could add space time to the formula as well, but I am not about to undertake theat one.....maybe I'll call my physcisist bud and run it by him.

[Ruune]

I've toyed with a similar idea- although I was going to vent through the cupholders.

[jleger98]

Hah...well if someone wanted to get real fancy they could add space time to the formula as well, but I am not about to undertake theat one.....maybe I'll call my physcisist bud and run it by him.

My head already hurts. For a while there I felt like I was back in HS physics

[Domsz06]

Dom, I think in your case, you are going to need to exchange the heat outside the compartment, but for most setups (2 amps) there is really no need.

Even so, you should be able to just add a vent or 2....no forced cooling.

I planned on doing that. This is why I thought about pulling from the bottom of the boat, as since it's on the water, and the water is cooler, it should be a cooler air. but then we got started on the gas fumes. So what I'm toying with now, if the just air exchange doesn't work is this.

(ok, you know it's friday and your bored at work when you think this one up)

Using the built in tige cooler, fill it with ice. Run a fan that would suck air out of it, and up into the compartment, since the ice and the cooler (full of soda right ) will be very cool, right around 32, the compartment should have no problem staying cool with that type of air blowing over the amps.

The problem I'm having, is how Can I pull air out of the cooler, but still keep it water tight so that water isn't leaking all over and the ice makes it past 30 min in the +110 F bako days.

Just an idea, but I'm hoping just the air blowing on the amps will be ok. I do know that when I leave the compartments cracked while driving it promots enough air that the amp is fine, just wonder how it will be with 6 ppi amps, as opposed to just one and two regular amps.

[jleger98]

Using the built in tige cooler, fill it with ice. Run a fan that would suck air out of it, and up into the compartment, since the ice and the cooler (full of soda right ) will be very cool, right around 32, the compartment should have no problem staying cool with that type of air blowing over the amps.

The problem I'm having, is how Can I pull air out of the cooler, but still keep it water tight so that water isn't leaking all over and the ice makes it past 30 min in the +110 F bako days.

NOW YOU'RE TALKIN!!

If your cooler is similar to mine, you can get at it from underneath. All you gotta do is put the intake end of your blower as close to and as low as you can get it. If you got ice in the cooler you'll feel the cooler spot. Run a hose over into the compartment and viola!!

OR you could just find a marinized airconditioning compressor and mount it on your engine. That way you could ACTUALLY air-condition your compartment.

OR just drop a block of dry ice in the compartment before you go out.

OR you could put a scoop on the bottom of the boat (or T off the water intake line) and run it through some sort of radiator contraption in the compartment.

Oh hell, just go buy some water cooled amps

[Domsz06]

they don't make water cooled amps, least none that I have seen, although I have toyed with the idea of running a small pump to some small lines and wrap them around the amps that way it would be water cooled. Using like a small aquarium pump. Circulate it through an ice cooler with water in the bottom, be money in the bank right now.

Your cooler is just like mine so I could just do that as well. Who knows really, I"m just hoping that it doesn't matter and the first, easiest solution works.

My other option is to just not use PPI amps and upgrade to a better one, but since I have all matching PPI's I really don't want to. Took me some $$ and looking to find them all. Plus they are all underrated, so they KICK @$$ when it comes to bumping!