Crazy radiator idea
 

A weird radiator idea

Construction materials: Aluminum sheets, and piping


Build a car underbody tray out of the aluminum sheets. Make sure all the sheets are solidly physically connected together. They don't have to be welded, but atleast some overlap and firm pressing.

Zigzag a few times along the length of the car, under neath, pressed against, above the aluminum sheets some form of piping that conveys heat decently well. Have it distribute the heat from the piping into the aluminum sheets.

Have the engine coolant run through the pipes before it hits the radiator. This will reduce the need for a radiator.

Insulate the exhaust manifold (or header), exhaust pipes, and for the hell of it, even the muffler.

This will reduce under car temperatures, which will allow the sheets to cool down from undercar wind.

This will in effect make the underside of your car a radiator.

The next part of the trick, is to use a temperature controlled grillblock.

Completely using plexiglass block off the top grill. For the lower grill, use any of the forum's designs for temperature controlled automated grillblock.



Put some tape over the cracks into the engine compartment for the hood, headlights, etc. Get it pretty well sealed off.


I'm not sure how well this would work, but it was an idea.


What inspired me was reading an article about running the coolant fluid through the frame of the car to reduce radiator dependancy.

This is a potentially awesome idea. You could run a 95% grill block year round.

As long as someone lives in a colder climate this should be OK, although just running a cardboard grill block and underbody corrugated plastic (coroplast) should be fine in that situation. If someone is doing a lot of stop/go driving in higher temps they may need a normal size radiator with a fan to make wind and remove heat.

I wasn't saying getting rid of the radiator. I was saying self actuating grillblock.

In theory, I like the idea until the first time I get stuck in bumper to bumper traffic on a 95F day and have all that heat radiating upward through the floorboards. Practically, I think it's going to be risky, as one medium sized rock between the wheels and you just lost all your coolant.

I do think there's potential there, but there are also significant engineering challenges to make it something that won't create new vulnerabilities and liabilities.

Yep, radiator is needed the most when the car is stationary.
Having the heat soak up into the car and the vulnerability of underneath the car is an issue, given the aluminum must be thin if spread out over a large area, or it would add a lot of weight.
Note that in the Prius hybrid, the engine is stopped when the car is stopped! So the radiator would only needed when the car is moving.

I have another novel approach for a radiator I'm going to be testing in the MGeo.

Angelus,

As I recall you mentioned that you have a late model Aveo. As far as I'm concerned you can turn the entire car into a radiator and it won't improve your FE. But you certainly will be warmer in summer months... :eek:

You said it's a crazy idea.

I agree. It is. :D

I think it's a great idea if coupled with auto engine start/stop. And keeping the heat out of the passenger compartment is nothing that couldn't be solved with a bit of insulation. The aluminum could also be close to 1/4" and still be very light.

Some copper tubing for the antifreeze and a bit of heat transfer grease such as used in computer heat sinks or even some old fashioned soldering of the tubing to the aluminum would be conducive to the heat conduction. And with such a large surface area, the lack of air flow at a standstill may not even be a problem.

This would be most beneficial for a vehicle that is mainly used on the highway for the same reason a full grill block would be most helpful for a highway vehicle; ie high amounts of air flow.

This mod is nothing without its entirety

You either automatic/manuallyadjustable actuating grillblock AND do the underbody radiator, or you don't do the mod at all.

I once had a classic Beetle with a/c; the condensor was under the floorpan. It took a helluva beating down there.

If someone doesn't want to do a mod this extensive, they could just build the underbody cover for near the front bumper, use a refridgerator backing, run the coolant through that, as its pressed against the alluminum plate, and then do the actuating front grill block mod.

I like the idea. I was thinking of a similar mod that would use an aluminum hood with counter-flow pathways in it, so that the heat would rise giving better natural convection while stopped. I haven't done the math, but most radiators are specified based on surface area so your under car area would need to be around that range to compete with the original radiator. Another idea to allow the use of a radiator while reducing drag would be to place the radiator is such a place that the inlets could be 'NACA duct' shaped. I think I'd want it on the bottom as part of a belly pan for center of gravity and beauty reasons.

+1 Really like the idea. Much better way of dealing with convection to prevent overheating in the car in stopped traffic. The only problem I see is opening and closing the hood without kinking hoses and the weight of the hood full of 2+/- gallons of fluid (an added 16 pounds, plus the weight of the additional layer of aluminum and ducting), but the engineering challenges seem far better than the undercarriage. Obviously engineering it so the hood would fold, like an OEM hood, would remain a priority to prevent decapitation or passenger compartment hot steam injection, but again, I think these issues could be overcome with the right thinkers.

The gain is what exactly? :confused:

the gain would be to get rid of the grill openings. I think there are better ways to get around this, especially when the goal is hyper-milling, but if it were to be done I wouldn't make the hood hold the entire amount of coolant, but I would install a higher flow water pump to move the water faster. I'm gonna break out my heat transfer book and see what kind of cooling is achievable from a hood and under the car for kicks.

The engine compartment needs ventilation, radiator or not. Heat, ozone, fumes, etc. kill all the non metal parts.

not to mention that the car has to have an inlet for the combustion. I see your point.

This has the problem of heat coming off the hood would distort your vision.
And how do you open the hood.

If the goal is just a grill block, you can make it actuate so its open when the fan is on, and closes with the fan off, much like a Porsche Spoiler raises up only when the car is going over xx mph.

ive been thinking of ways to accomplish something similar far longer than this thread has been up, but my thinking was more towards the AC condenser (I think that is what it is) thus no longer blocking the radiator, and allowing for better cooling from it.
there are several ideas I toyed with, but the one that I felt was easiest accomplished was by using 2 pieces for the condenser, and putting them on either side of the fender, with a series of small, thin vertical cuts along that portion to allow the air flow to pull heated air from them while moving, and maybe a low fpm fan for when stationary.
this would allow a much larger area of grill blocking since the air would no longer be blocked and heated from the AC portion that sits in front of it.
as far as removing the rad, and replacing it with a hood system, it could be accomplished in the same way.
to keep the engine bay cool and allow gases to escape, a couple of inverted slits along the hood itself would accomplish this, and all you would really need is a small slit in the front for air flow. I mean, look at that aerocivic, it has almost no frontal inlet for airflow and has no problems that I know of.

all in all, I think its a novel idea and something that could be pretty easy to accomplish
with just a little bit of ingenuity and some trial and error.
heck, you could do both if you chose, 1 part at the hood and 1 part in the undercarriage.