Ventilation Inlet Mods

[rh77]

Something occurred to me as I changed the oil yesterday and cleaned the debris and leaves away from the ventilation air inlet near the wiper resting area...

(now that Summer's over, and the A/C probably won't be required until next year... )

With the hood closed, the vent inlet "grate" has less than 1" of clearance between the hood. Since this region is generally a low-pressure area at highway speeds, the air is probably sucked from the engine compartment (which I can attest is HOT air most of the time through that vent into the car).

Proposal 1)

Rig-up something to re-direct fresh air into the inlet (with a mild scoop or similar). Question: would this create more drag than it's worth???

Proposal 2)

Let's say I stop by the ice machine before I leave work and fill a large travel mug (the cubes are nearly "crushed" sized -- not the big chunks). If the ice is dumped down into the inlet, would this effectively act as an evaporate chiller for the incoming air? Water production shouldn't be an issue, since built-in drains handle rainwater.

Is this a viable idea for alternative A/C???

RH77

[boofighter]

could work in theory, but it might lead to a really humid ride home.

[bones33]

In the days before widespread A/C there was this thing that hooked on to a rolled up window. It scooped in air from the outside and ran it past a small block of frozen CO2, (dry ice). It probably kept the drivers head cooled off pretty well.

Convince the boss to get a dry ice maker for drinks. Hey, it's almost haloween!

[rh77]

Originally Posted by beatr911

In the days before widespread A/C there was this thing that hooked on to a rolled up window. It scooped in air from the outside and ran it past a small block of frozen CO2, (dry ice). It probably kept the drivers head cooled off pretty well.

Convince the boss to get a dry ice maker for drinks. Hey, it's almost haloween!

There's a thought -- our research campus has live-in volunteers for early-phase drug research. They have to ship refrigerated lab samples to a central-lab using:

Dry ice! I bet they have leftovers at the end of the day...

[oneinchsidehop]

Originally Posted by rh77

Something occurred to me as I changed the oil yesterday and cleaned the debris and leaves away from the ventilation air inlet near the wiper resting area...

(now that Summer's over, and the A/C probably won't be required until next year... )

With the hood closed, the vent inlet "grate" has less than 1" of clearance between the hood. Since this region is generally a low-pressure area at highway speeds, the air is probably sucked from the engine compartment (which I can attest is HOT air most of the time through that vent into the car).

Proposal 1)

Rig-up something to re-direct fresh air into the inlet (with a mild scoop or similar). Question: would this create more drag than it's worth???

Proposal 2)

Let's say I stop by the ice machine before I leave work and fill a large travel mug (the cubes are nearly "crushed" sized -- not the big chunks). If the ice is dumped down into the inlet, would this effectively act as an evaporate chiller for the incoming air? Water production shouldn't be an issue, since built-in drains handle rainwater.

Is this a viable idea for alternative A/C???

RH77

AFAIK this is a high pressure area and thats why it works so well for "ram air" hood scoops. Hot rod mag prepped a car for Bonneville and found sealing off/ transitioning that area was good for a .01 reduction in drag (I think I'm remembering it correctly, anybody have that link?)

Sooo... little scoop there? not needed for intake ventilation. more drag? eh, if we rent a wind tunnel we might figure it out.

As far as the cooling? I'm gonna try it today. I think it brilliant. (of course it's only supposed to be about 70f today, so I'm probably gonna be cold.

[Steve Peters]

My two coolers (desert =dry air):
1) Fill the vents with wood shavings and send a window washer inlet in there. Cool air at first, but gets humid unless this air is evacuated quickly.
2) Fill a new, trigger-and-tube style garden sprayer with sterilised water.
Either pump pressure in by hand and trigger-release spray into path of incoming air, or attach a quality 12V compressor to sprayer tank for permanent running. Once again, thru-flow of air is essential.

Care! Legionella bacteria are only dangerous when inhaled. They exist in many water sources and multiply when lukewarm. Use boiling, chlorine tablet, etc to sterilise.

[rh77]

So I tried ice in the inlet area last week, and it just got humid in the cabin. The outside temp was 75F, but it seemed the same temp inside, but with added humidity...

My two coolers (desert =dry air):
1) Fill the vents with wood shavings and send a window washer inlet in there. Cool air at first, but gets humid unless this air is evacuated quickly.
2) Fill a new, trigger-and-tube style garden sprayer with sterilised water.
Either pump pressure in by hand and trigger-release spray into path of incoming air, or attach a quality 12V compressor to sprayer tank for permanent running. Once again, thru-flow of air is essential.

Care! Legionella bacteria are only dangerous when inhaled. They exist in many water sources and multiply when lukewarm. Use boiling, chlorine tablet, etc to sterilise.

I think the problem was, in fact, a lack of high-flow air. The blower fan on high probably isn't sufficient as a air mover. A "scooplet" might be needed to test out air flow first.

Regarding the bacteria, wouldn't this be present in most air-con systems? I've seen nasty, old window units cause this problem when I worked in EMS, but I haven't heard of this in vehicles. Sometimes I'll get a blast of moldy air, which is great for the allergies, tho. I'm assuming that the use of additional water could create a breeding ground for this stuff.

RH77

[ffvben]

I just took out an incabin air filter after 50k it was black and full of junk, the new filter is white. I also use frigi-fresh, just turn the ac on using outside air, spray it the grill near the wipers and it supposedly kills bacteria inside the vents/fan and coats the surface to kill for a while. also don't breathe this stuff in for the first few mins it will make you grow another head
Instead of ice can you freeze a few coke bottles if it fits? this way only sweat is produced and you can re freeze the bottles, cleaning them every use to lower bacteria.