Question of Aerodynamics

I am not an expert, but I think that you have some validity with your point. However, that depends on so many factors like distance from screen to radiator, radiator's permeability to air, etc. The radiator may be the gating item.

The easy way to determine the outcome is to do some empirical testing.

I'd say the only way you'll know is to test.

But my guess is that the area will be plenty anyway..I don't s'pose it was 'designed' in the first place..someone prob' just made a big hole and covered it with 'stuff' to keep other 'stuff' out.

It smacks of 'overthink' to me...

If it was the air inlet for an F1 rce car I'd be worried... but air inlet for the rad...surely not a precision bit of design...?

I'm going to hide now so Blink can't get me...

That's my thoughts too Del, they didn't do any testing, they just guessed at best.

I'm going to hide now so Blink can't get me...

Del, you miserable wretch....

Actually, I agree with you and Labyguy. Just try it. It will probably work. I just put together an entire vehicle out of popsicle sticks and chewing gum, and it works just fine. Granted, I had a momentary impulse to say "you really ought to look at this with CFD," but sheesh, it's a darn diesel rad. You can probably throw together something, and test it in the real world in about 1/4 the time it would take to just find the drawings to even begin to use CFD!

Two things come to mind, 1) that the screen is used to prevent airborne contaminants (bugs, pollen, etc.) from reaching, sticking to and fouling up the radiator, rendering it less efficient, and 2) that the bends (pleats?) increase the surface area, so the screen itself would take longer to clog up (and experience reduced air flow). A louver would be less likely to clog up, but would not filter the contaminants either.

Yes, yes, and again Yes,

What I'm finding is that no mater how valid my arguments, the reply will always be "What if...." I have an endless battle of defending my ideas against "What if..." I wish I could play that game... it would go like this..

"What if a rhino escaped from the zoo and charged the radiator, will the screen protect it?"

or

"What if woman wearing a sun dress walked by the radiator when the engine was running, would the fan rip her dress off and block all the air flow?"

It seems I just can't engineer out all the "What if's..."

Going back to my "dum' ol' farm boy" experience (before becoming a dum' old engineer), it was common for farm equipment radiators to have a "pleated" perforated metal screen to keep chaff, bugs, straw, leaves, and other stuff from plugging the air-side of the radiator. When in got blocked and caused the water to get too hot, it was time to stop the equipment and knock off, scrape off or blow off the screen.

I would guess it was sized by finding the free air area of the radiator, selecting an area of perf metal that matched the free area required, and sizing and pleating it to match the desired shape of the radiator.

A number of these screens would be replaced with a perf. metal spinning wheel that would be less prone to plugging because the centrifugal force would keep the chaff from sticking.

I don't know where your particular diesel engines are operating, but be careful of air born contamination plugging a radiator. Even in urban areas there can be air borne debris that can cause the engine's cooling system misery. Sometimes it takes a lot of work to make something new and convince people it will work.

I want more about the woman in the sun dress....

Labguy:

I am an automotive designer from waaay back. Remember when there weren't any warning stickers on cars???? Now you have a warning sticker on everything imaginable. For example, on the fan shroud you have a warning sticker to warn people from sticking their fingers in the fan blade. Engineers/designers now have to make everything "idiot-proof". Just remember this when you are designing your screen.

What's the problem with making things idiot-proof???

They keep making a better idiot.

Good point, I have to revise my sticker,

"DO NOT STICK FINGERS, TOES, HAIR, EARS OR ELBOWS INTO MOVING PARTS OF THE FAN!" (knees are ok, but not ankles)

Or better yet,

"KEEP OUT, YOUR TO STUPID NOT TO GET HURT!"

I wonder if marketing will go for that last one?

The trouble with making things idiot proof is that the idiots keep trying new dumb things to get past the protection!