air to water intercooler design experience

[Hans Blom]

Hi, i've been doing some research on air/water intercoolers and thought I might start a thread just on these in particular. I have read various threads where they are brought up and talked about a bit here an there, but not too much on the intercooler itself other than...pick an efficient one...

Your intercooler: From a design standpoint obviously you want one that will flow as much as possible for the allowable space in your car and with as little drop in PSI from air flow across the core. With knowing how much cfm you motor comsumes at max rpm you can pick a cooler with more cfm available...as in if my motor uses 1000cfm, a cooler that will flow 1500cfm should do the deed. as well you need to know the pressure drop at that rpm...fopr example some advertise a cooler rated at 1500cfm with only .2psi drop....This seems very good in my eyes, but maybe i'm missing something. I have done lots of reading in the past of air to air with regard to end tank design a flow, but all in all it really is a measure of how much pressure drop correct?
Another aspect is the core itself, where i have read the core on a air to water has smaller passages for the water to travel through and some manufacturers uese air to air cores which is not as efficient. I'm not sure I completely agree with this in it's entirety or in our application as you can vary your water flow to be able to manipulate how long the water in in the core which ahs a certian surface area which you are trying to extract a certian amount of BTU out of by the time the water leaves the core. All this will depend on temp of compressed air, surface of core, temp of water and flow rate...the temp of the water will of course be getting warmer the further you make it down the track.

Tanks: I have read a good estimate on amount of ice for your tank is about 10# per 100hp, so for 1000hp, you want 100lbs of ice and you can build your tank to suite....or as large as feasably possible, large being the opperative word. Insulate your tank and lines to the cooler. Have a large enough fill hole that it is easy to put in ice (and beer from another thread ), a drain petcock and a vent(maybe not needed?)
Pump: Any specific criteria here other than to get a quality one. Flow 'should' be determined by above mentioned BTU extraction if your getting technical, but I guess you won't have a problem with too high flow...

All above is just ramblings from an unexperienced air to water intercooler dumbass so feel free to pick it apart and give any advice or experience you have had with your system...that is what it's for....Hans

[jl222]

  Hans... one thing to watch for is that the outlet for the water is at our near the top of intercooler tank, otherwise how are you sure that water is flowing through top tubes. It seems that some intercooler manufactures are using higher volume pumps and smaller intercoolers these days, it used to be 6 gal min pumps and now we use a 55 gal min pump with a 12 x12 core we have a 35 gal tank [ a bit overkill ] with 3 compartments but usefull for weight if needed.
  Not sure about 10 lbs of ice per 100 hp, we use 6 of the small bags  that are normally for sale [71/2 lbs?] in last compartment  and over 2000hp.

[Seldom Seen Slim]

Yanno, as I read these many comments about ice -- I think of the Ohio State fuel cell car, whose team took their own icemaker to the Salt for the Shootout.  But while I could -- I don't think I want to have the responsibility to station someone at the ice machine all day to serve those folks (like youse guys) that need ice. 

And anyway, don't forget that for the past few years there's been an ice vendor on the Salt for Speedweek.  You don't need to buy multiple bags of ice before leaving town for the day.  But in case you want to do it that way -- Smith's Grocery store, in western West Wendover, has been stationing a large refrigerated semi full of ice at their parking lot for Speedweek, and I think they open pretty early during the event - just to serve the racers (although locals ARE allowed to shop early and stock up on tortillas).

[Hans Blom]

JL, As far as placement of intlet and outlet of your water fittings on the intercooler I would think you would want them in the middle and if possible with some distance between your welded fitting and the core of the intercooler...meaning you have a small tank on each end. I have seen some very nice and high dollar, high HP coolers with virtually no tank at though as well. My thinking is that with the viscosity of water it gives it a bit more time to flow to the outer tubes, as with any pressure vessel the pressure will try to equalize(or will) in the closed system but you will still have more flow right in front of the fitting, and the water will always take the path of least resistance. On the other hand if one of your inlets or outlets is at the top ot bottom(staggered), for sure I would think to put the opposite fitting at the exact opposite, so if you had an inlet at the bottom, put you outlet at the top. In my mind I look at it the same for the air side as the water side when dealing with distribution, it's all just fluid flow, they just have different viscosities.Here is a couple pics from Bell, who make very nice exchangers in my opinion. the first(Bell1) being a fairly traditional 12x6x6 rated at 400hp and the second(Bell2) being a bit more your style which actually has 2 cores at 18x8x10 each inside and rated for 3000hp. This small one has virtually no water tank on the ends, wheras the large one has 2 inlets/outlets for better distribution. it might be insignificant, but i would like to see a bit more 'tank' on the smaller one...I'm sure they would appreciate my advice...

SSS, yeah, I saw an old post you had mentioned the ICE TRAILER...good to know thanks..

[mkilger]

In our roadster I was able to put a 48 gal intercooler tank, less core and pump of course, should about do it I hope. and we got an ice maker for Bonneville too

[Hans Blom]

And yes in retrospect 10# per 100hp does seem like alot, seems you have a very nice system...nice and large....55gpm, wow that is moving some water! so a 12x12...what is the depth? Is the air blowing through the short side so you have short tubes for the air to travel though?

I have sent a few emails to intercooler companies but haven't gotten any response back on how the efficiency is rated as far as pressure drop. As said in first post some advertise .2psi drop and rated for 1500cfm...but is this at 1500cfm...and at what pressure is this drop recorded at?
Hans

[Hans Blom]

In our roadster I was able to put a 48 gal intercooler tank, less core and pump of course, should about do it I hope. and we got an ice maker for Bonneville too

You couldn't fit a 49 gallon???

[Seldom Seen Slim]

No doubt he elected to leave room for the beer.

[Jonny Hotnuts]

I feel an easier way to approach the HP vs size is to use about 10-20% more then the rated HP of the intercooler for B-ville. 10# per 100 HP seems like too much. We ran 450-500hp and used a cooler with about 3-10 pounders and have tons of ice left after the run.

One thing I would recommend is to make sure your outlet into the ice tank is on the opposite side of the feed. I have seen a few installations where the inlet is over the feed in a rectangular tank and causes one side to have ice and the other to be water. Having the feed lines on opposite sides causes the water to flow longways over the ice as apposed to taking a shorter path.

~JH

[jl222]

No doubt he elected to leave room for the beer.

   I've always thought that would make a great commercial, make a fast run get out with a big smile open the deck lid and pull out Budwisers for the arriving crew Whatcha think Budwiser?

               JL222

   

[SPARKY]

You might want to approach COORS---they float---Buds sink 

[joea]

just keep the system flushed....that way....plenty of margarita
mix.....and etoh helps keep it colder........at the end
of the run.....open bypass/drain.....works well on smaller
systems....at least cheaper to keep stocked...

[jl222]

 Hans... the core is 12x12 there is no short side, on our design the air blows into a 4in tube at the bottom turns and goes up 12 in through the intercooler and exits through another 4 in tube in the opposite direction. the water flows thru two 1 in
plastic tubes from pump and enters intercooler in two places in middle of intercooler 1 in wide tank and flows horizontal
through 12 in intercooler core and flows into another 1 in tank and exits through two 1 in tubes at top of tank and no air gets trapped in top of core as in other mid tank outlet designs.

                    JL222

 
 

[maj]

Anyone tried dry ice and methanol ??

[38Chevy454]

Anyone tried dry ice and methanol ??

Not tried it in a car, but it takes a lot of dry ice to cool down the alcohol to -40F.  If my memory is right, about the same volume of dry ice as alcohol being cooled from RT.  -40F alcohol gets real thick, like syrup.  We did it to quickly deep freeze some 2024 aluminum rivets to prevent aging.  It also gives off a lot of CO2 fog as the dry ice sublimes (solid to gas) as the dry ice is used up.