Intercooler modelling programs

[JustenGT8]

Has anyone come across something like this lurking out there? Seeing there are a myriad of turbo sizing and supercharging programs out there, some knowledgable soul might have developed something for intercoolers as well? Lots of variables to play with so something like this would cut down my calculator battery use a heap

Edit: seems there are I didn't think google would deliver, but it's found a couple so i'll have a play and report.

Edit of edit: no good so far

[tomvale13]

All I can find are ones that are used to prove something but are not editable, ie; spreadsheets converted into PDF's to sell someones invention..

[JustenGT8]

Still no joy but have done some initial calcs on what i currently have to play with.

Existing china spec bar and plate cooler 100x300x600. Seems to work OK but not alot of hard data. Flows easily enough air for 400rwkw @ 16psi. With WI i have never seen intake temps above 35deg at full boost...even @ 31deg ambient.

x-section flow area = 9750mm2
flow path = 600mm
frontal area = 180,000mm2

New core. Vertical tube and fin style 590x290x70. Also china spec i suspect and quality is patchy. Tubes are fine but end plates and internal turbulators are a bit shite. The turbulators themselves are OK but they have pretty average contact with the tube so heat transfer won't be as good as it could/should be. But:

flow x-section 170% greater
flow path 50% less
frontal area 95%

So, there's less time for heat exchange to occur but with more runners there's effectively more air in contact with the tubes for heat exchange. I'm not sure how to go about comparing the effective efficiency of the 2? What's more important..area of contact for heat exchange or time in contact with surface?

Tube and fin is ALOT lighter.

Ideally i want the tube and fin 100mm thick (which is what i ordered ) which would give me a massive 240% increase in flow, plus alot more surface area for heat exchange and knowing how effective the WI is i'd be confident this would be the way to go.

As seems to be the trend these days it's not a clear cut call

[Supra967]

the heat transfer side is failry involved, and you need to know a bit about what the air is doing either side. Most likely easiest to log and test manually.

Total internal fin-air contact area is the main thing in the equations that you want to compare. You can (maybe incorrectly?) assume all else is similar. The bar and plate looks like it has a bit more internal contact area per unit of flow area?

The lighter one might be better for track as it will cool down quicker off boost?

[love ke70]

id be saying, if you already have the dodgy china spec tube and fin, and it wasnt what you wanted, what have you got to lose by installing it?
air in contact is the important, not necessarily time in contact, the gaps between the fins on my water to air intercooler are absolutely tiny, and it works better than anything.

even if it cools the same, you have better flow, and you drop some weight, its all a win isnt it?

[JustenGT8]

No chance of testing them back to back as completely different intake piping....that's part of the decision, quite a bit of work to reconfigure for a vertical core IC. My gut feel is it will be worth it and it was the way i originally wanted to go...tricky though and was talked out of it by fabrication mate.

Some back of the envelope calcs to compare should be enough to determine the quantum of the difference? If it's large i'll give it a shot,, if it's bugger all i'll probably just go with a similar FMIC configuration but source a lighter tube and fin cored (HDI maybe?)

[Supra967]

In its simplest form the equation is q=UAdT

U is the overall heat transfer coefficient, which at a guess would be pretty much the same between cores (similar materials/air flow etc). Leaves surface area as the comparisen point.

Measuring every bit of surface area would be great fun, but maybe a waste of time. I'd imagine the air flow tubes/plates are similarily spaced on each? If so just look at an individual tube on each and see which one has more internal surface area. Or perhaps you can get a value for the perimeter of a section of tube on each, then just multiply based of overall size.

[wilbo666]

One could set up a form of empirical testing.... ?


Maybe something such as pumping hot water through each intercooler (at the same mass flow) while measuring the inlet and outlet temps, and the core pressure drop for example....



Cheers
Wilbo

[JustenGT8]

In its simplest form the equation is q=UAdT

U is the overall heat transfer coefficient, which at a guess would be pretty much the same between cores (similar materials/air flow etc). Leaves surface area as the comparisen point.

Measuring every bit of surface area would be great fun, but maybe a waste of time. I'd imagine the air flow tubes/plates are similarily spaced on each? If so just look at an individual tube on each and see which one has more internal surface area. Or perhaps you can get a value for the perimeter of a section of tube on each, then just multiply based of overall size.

One of the biggest differences between cores is their heat transfer capacity in surface area....it's why some china cores are pretty good and some are complete shit. The types of internals fins, their density and their arrangement are all very important and not just for the surface area but how they interact with the air eg same density of internal fins between 2 cores but one uses offset fins and the other are a simple row.

In this case the cores are very different in every aspect. Core shape, spacing, fin density etc. The tube and fin will flow more for sure (both internally and thru the core to the radiator) but i'm concerned how well it will cool.

I was hoping someone had done the hard yards and had some figures for this type of thing, like they have done for turbo calcs etc?

[love ke70]

would there be a way of doing this with hot air instead of hot water? to give a more real world experiment?

10 hairdryers plumbed into some PVC pipe?

[JustenGT8]

Ever seen a dyno fan? and they don't even come close to the airflow you get on road....no way to experiment with this.

I either try a gazillion calcs playing with options or find a calculator that is set up to do the same

[JustenGT8]

This gives a pretty decent run down of all the theory and what i'm up against trying to guestimate numbers to do a comparison:


http://www.gnttype.org/techarea/turbo/intercooler.html

This is the only calculator i can find and you have to buy the whole thing, which might be interesting but not what i need.

http://horsepowercalculators.net/int...ler-calculator

[trdee]

The problem is that every intercooler will have a different overall heat transfer coefficient (due to the materials used and the efficiency of the design), which affects the calculations. Unless you have a half decent idea of what the overall heat transfer coefficient is, then trying to calculate it from the Q=UAdT formula is not going to give you a useful answer.

[JustenGT8]

The problem is that every intercooler will have a different overall heat transfer coefficient (due to the materials used and the efficiency of the design), which affects the calculations. Unless you have a half decent idea of what the overall heat transfer coefficient is, then trying to calculate it from the Q=UAdT formula is not going to give you a useful answer.

Yup

Just like the turbo calcs out there i was hoping someone had done the hard yards based on the types of constructionetc. There's very good info on the ARE site on the types of cores etc so i have a good gut feeling for what will work and what i want. It would just be nice to back that up with some rough calcs, eveb if only to give a relative comparison.

I'll have a crack with the 2 set ups described in the 1st post and see how they theoretically stack up?

[trdee]

Hmm. Unfortunately I think you wont find what you're looking for. As every single manufacturer is going to have different OHTCs. And I highly doubt those chinese factories actually "design" the heat exchangers, they'd just make em to a size, which means they would have nfi of the OHTC of the cooler you have bought

You can get rough values for typical OHTC ranges for different types of heat exchangers (ie typical tube and fin vs typical bar and plate), but they wont give you any better indication than what you already know.......... best bet would be to just give em both a go and log the temps/pressure drops.