Any benefit from air straighteners?

[Peter7307]

This is a little thinking outside the square so feel free to chime in with what ever comments you think might apply.

Vehicles are subject to turbulent air , both from natural winds and other vehicles, as they drive along and with grill blocks the volume of air flowing through the radiator is diminished anyway.

So my question is this:
Is there any benefit from fitting an air straightening device to the car to minimise the turbulence factor of the air flowing through the radiator?

Clearly this is not a priority for car makers but for an Ecomodder it may be worthwhile.

As I said above...any comments welcome.

Peter.

[Daox]

Air going through a radiator is made turbulent by the radiator on purpose to increase heat transfer. If you straighten the air you diminish the pressure differential between the front and back (thus decreasing drag) and also decreasing the cooling capacity of the radiator.

[Bill in Houston]

what is an air straightening device? can you post a link to a picture?

[Peter7307]

Daox,
The idea is the put the air straightener ahead of the radiator to introduce "clean air" (in the aerodynamic sense) to the matrix as opposed to having the radiator sit in a disturbed air flow.

Bill,
I don't have a picture or a link.
What I had in mind was a box structure to sit ahead of the radiator and let the air enter the radiator in a more controlled fashion.
The logic being this would then allow a smaller radiator for the same job.

Most formula car designers go to great length to make sure their radiators sit in clean air within the limitations of the rules so this is an extension of that idea.

The best I can think of just now is a lightweight box the same dimensions as the radiator matrix. Into this box is a series of tubes or vanes to direct airflow similar to an egg crate arrangement used to separate glasses or bottle inside cardboard boxes.

Peter.

[Exalta-STA]

Hi Peter, have you tried radiator cooling plates? I am actually thinking of giving them a try since they focus the air coming from the grille and bumper into the radiator..

I'm thinking that aside from the top, I could add plastic plates on the side and bottom of the bumper and these would funnel the air into the radiator...instead of the air passing through somewhere else...

Would this result in more drag though or would it be cleaner aerodynamically?

[Frank Lee]

I've read (IIRC Hucho) that a properly designed radiator inlet/outlet duct system can theoretically add thrust due to the addition of the heat energy. Since they said "theoretically" I take it nobody has done it, or measured it?

That said, I don't know all the ramifications (pun!) of having such a system.

I do recall that my '64 Spitfire had nicely ducted flow to the radiator, probably to help a marginal cooling system with marginal inlet area get the job done. Careful attention to ducting may allow a smaller radiator to work, or allow the energy-consuming fan to come on less. But if the vehicle doesn't have a cooling system deficiency I don't know what gain there could be.

[Bill in Houston]

Yeah, I don't see how what you are describing could help anything. But then again, I still have no idea what you are actually talking about.

[Phantom]

An air straightener looks like this that is the first image I found but for the most part in a screen that is atleast 2-3mm in depth that calms the air. They are often used in front of the cars MAF so that it can get accurate readings.

Exalta-STA I like those pics I have thought about doing that on my car to force the air into the radiator instead of having a way to go over it.

[TomO]

Mythbusters was good for at least one thing, lol. If you want to experiment with this idea, just buy boxes of drinking straws and cut off the ends of the box:


You can then place them between the bumper and radiator and test. If they don't work or negatively affect things, you then have straws to put into your drinks this summer!

I run a home-made cooling plate for my radiator on my VX, it was made from a strip of plastic and Gorilla Tape. Has been holding up for a couple years now through all the seasons. I have also taped the sides of the radiator so that all air coming in through my (reduced size) front bumper is directed through the radiator:

[Bill in Houston]

Ah, right, thank you. I have seen a bundle of straws used for the same thing. You know, a radiator itself looks a lot like an air straightener to me...

I guess if you had a radiator that was undersized, and had reason to believe that airflow was only going through a small portion of the radiator, then maybe a straightener would do something. I don't think that rads are undersized on any production cars these days.