The Technical Questions Thread

[csl177]

Couldn't water be filtered in much the same way fuel is? 2 or 3 stage carbon filters are very effective at getting contaminants out. Of course they need periodical replacement, but air, fuel and oil filters do as well.

If you mean for drinking/potable water, coming soon are carbon nanotubes but for now there's reverse osmosis filtration, or on a basic level this: Survival Water Filter Straw

A lot of water-born diseases are being avoided by distribution of the simple version in the third world. Pretty much standard in most campers kit anymore.

[Sledgehammer]

You could always setup a distillery in your car

[NSXType-R]

Couldn't water be filtered in much the same way fuel is? 2 or 3 stage carbon filters are very effective at getting contaminants out. Of course they need periodical replacement, but air, fuel and oil filters do as well.

I don't think fuel filters are made of carbon, but I wouldn't know.

I guess what you could do is try and distill water from the exhaust heat. That might be cheaper than using filters, but I'm sure it's pretty complicated to set up.

[Magnum9987]

but, if you need large portions of water (like 3-5 gallons in a small car, or try 20-25 in a large truck) distilling using exhaust heat would be impossible, or take an incredibly long time. A complex exhaust, a condenser, and all the piping would negate one of the principal benefits of using a 6-stroke, which is to eliminate the cooling system.
Which would mean filtration is the way to go, but again, they need periodical replacement, and possibly alot more frequently than a fuel filter, which could be a serious pain in the ass to replace.

[NSXType-R]

but, if you need large portions of water (like 3-5 gallons in a small car, or try 20-25 in a large truck) distilling using exhaust heat would be impossible, or take an incredibly long time. A complex exhaust, a condenser, and all the piping would negate one of the principal benefits of using a 6-stroke, which is to eliminate the cooling system.
Which would mean filtration is the way to go, but again, they need periodical replacement, and possibly alot more frequently than a fuel filter, which could be a serious pain in the ass to replace.

Why are you trying to put a water filter into a car or truck?

[pimento]

Why are you trying to put a water filter into a car or truck?

Read the rest of the comments talking about a six cycle engine..

[NSXType-R]

Not a car question, but an airplane question. Close enough, they have wheels too.

Do piston engined aircraft have gearboxes? I know that they can vary the pitch of the propeller blades, but I don't think they have gearboxes.

I'm talking about radial engined aircraft mainly though.

[f6fhellcat13]

I think some have a final drive reduction, but you're right that pitch variation is the predominant way of varying thrust.
Most aeroengines are designed for maximized performance over a pretty narrow band, so, in theory, a gearbox would be a useful way of keeping it within that band. However, if you spin the prop too quickly, the accelerated air on the propeller's front face starts moving at sonic speeds, which introduces all kinds of shock waves and other problems and is generally to be avoided.

[NSXType-R]

I think some have a final drive reduction, but you're right that pitch variation is the predominant way of varying thrust.
Most aeroengines are designed for maximized performance over a pretty narrow band, so, in theory, a gearbox would be a useful way of keeping it within that band. However, if you spin the prop too quickly, the accelerated air on the propeller's front face starts moving at sonic speeds, which introduces all kinds of shock waves and other problems and is generally to be avoided.

How appropriate that this question was answered by you.

Thanks.

I do understand that the peak of max speed for propeller airplanes was reached by around the end of WWII, at around 450 mph because of that shock wave phenomenon.

[ruim20]

How appropriate that this question was answered by you.

Thanks.

I do understand that the peak of max speed for propeller airplanes was reached by around the end of WWII, at around 450 mph because of that shock wave phenomenon.

Hum, i was under the impression that the TU-95 flew faster than that, closer to 550mph (counter rotating propelers)

And the US had a crazy propeller plane, the Thunderbolt or something like that, it think it flew close to 700mph... I think.

[pimento]

According to the font of all knowledge, the fastest is the Tupolev Tu-114.

[NSXType-R]

According to the font of all knowledge, the fastest is the Tupolev Tu-114.

Sounds about right, the 450 mph I talked about was operationally attained, not experimentally.

[clutch-monkey]

the US made some propellor driven aircraft in which the propellor itself moved at supersonic speeds, i'll have to look it up. apparently standing on the deck of an aircraft carrier when it was going was quite an experience

[NSXType-R]

Hum, i was under the impression that the TU-95 flew faster than that, closer to 550mph (counter rotating propelers)

And the US had a crazy propeller plane, the Thunderbolt or something like that, it think it flew close to 700mph... I think.

Missed your post earlier, 450 mph was a rough estimate of what WWII planes got around to. Concept planes weren't counted.

the US made some propellor driven aircraft in which the propellor itself moved at supersonic speeds, i'll have to look it up. apparently standing on the deck of an aircraft carrier when it was going was quite an experience

I would be interested in what you dig up.

[clutch-monkey]

Republic XF-84H 'thunderflash'
nicknamed by crews as the 'thunderscreech'.

..the supersonic propellor set up severe vibrations and resonance that caused acute nausea in anyone standing nearby..