intercoolers

[Dakin Engineering]

Hope this is the correct forum, I'm building an EFI system with a W/A intercooler.
Is there  a formula to predict pressure drop in an intercooler?

Sam

[isiahstites]

Don't know if this is what you need but maybe it will help.

Scott

http://www.rbracing-rsr.com/intercoolers.htm

[Dakin Engineering]

RBR has been a part of my reference material for some time, lotsa good info.

And Well Done! for your effort this year.

Sam

[Harold Bettes]

Measure the drop on a flowbench at a known pressure. The rest is easy as you can select the intercooler on the best flow at a given pressure. You want to have the best ratio of flow vs pressure vs square inches exposed to the cooling media (air or water). That is sorta a simplification, but it will get you to the right answer the quickest.

Regards,
HB2

[Dakin Engineering]

Harold,
  I'm experimenting (read killing time) with building my own W/A intercooler with available (scrap) materials. The copper version is built and aluminum is in progress.
  I started with the cubic inch cross section of the intake and maintained or exceded the cross section thruout. I know there is some loss when changing direction, I was hoping for some math to apply.
  I'll get to a flow bench someday....

Sam

[Harold Bettes]

A cheap and easy comparator and a good one at that is to use your shop vac as the vacuum source and take a pressure (vacuum) reading on the side of the device to be evaluated. The measurement can be something so simple as a u-tube manometer with water in it. The water u-tube is measured against a plain ruler. 1" of movement is really two inches of water vacuum. The better the flow characteristics, the less the vacuum draw on the shop vac. Use a 12" ruler and the u tube can be made of plastic tubing that is about 1/4" id. You fill up the u tube with water up to the 6" level and you will have a very accurate measurement for up to 12" of water vacuum.

Unfortunately there are no super simple formulae to apply that would be as easy as that described above. It can surely be calculated and then would need to be flow tested anyway, so the previous description is really super easy to apply. The output of the shop vac is directly dependent upon the power (electrical) at the plug, so assuming that there is not a great deal of power fluctuation at your shop space, it will work as described.

TIP: Before fabricating a complete intercooler, you can measure the sections to select the best one to use. The same can be said of the tanks and the piping. You can first make up models of cardboard and tape to decide on a design before committing to welding.

Some handy equivalents are: 1"H2O = 13.6"Hg  1"Hg = .49psi

Enjoy. Good Luck.

Regards,
HB2

[Rex Schimmer]

Harold,
You must be staying up to late! 1" of Hg =13.6" of H20. I know you were just testing us.

Rex

[Harold Bettes]

 :-DYa caught me Rex

I guess that shows what a real problem I have for short term memory loss, er whatever ya call it! 

Thanks for the correction.

Regards to All,
HB2