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When it rains the atmospheric pressure is usually low, which means a carburetor runs richer.
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Didn't Tyrell use this in F1 years ago? I seem to remember it being the subject of a protest, breaking the rule about "power-boosting additives". I think the final somewhat bizarre conclusion was that it was an additive and did boost power, but was somehow NOT a "power-boosting additive".
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newatlas.com/bmw-water-injection-efficiency-power/.../
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..........................and the road being wet there is less friction for the tyres so it seems it runs better?
dvd
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..........................and the road being wet there is less friction for the tyres so it seems it runs better?
But energy is used by the tyres displacing water.
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newatlas.com/bmw-water-injection-efficiency-power/.../
V interesting, but two things puzzle me - firstly, although the object is to lower combustion temperature, it says a much higher compression ratio can be used...which surely must increase the temperature of the compressed materials. Secondly, it uses water from the aircon, which therefore must have to be permanently on during the 99.9% of the UK year when it is not needed, thus needlessly consuming energy!
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newatlas.com/bmw-water-injection-efficiency-power/.../
V interesting, but two things puzzle me - firstly, although the object is to lower combustion temperature, it says a much higher compression ratio can be used...which surely must increase the temperature of the compressed materials. Secondly, it uses water from the aircon, which therefore must have to be permanently on during the 99.9% of the UK year when it is not needed, thus needlessly consuming energy!
A/c isn't just about reducing temperature - it's more about reducing humidity, something we have a lot of in the UK so A/c is more useful in spring/autumn than summer - that's why mine's on all year round.
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I think the biggest drawback stopping manufacturers seriously persuing water injection is that the byproduct is lots of very hot steaming nitric acid. Great for exhausts...not.
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I seem to remember seeing 'Steam injection' units being sold which comprised of a boiler which was piped to ports drilled into the inlet manifold. Haven't seen any for sale for years.
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newatlas.com/bmw-water-injection-efficiency-power/.../
V interesting, but two things puzzle me - firstly, although the object is to lower combustion temperature, it says a much higher compression ratio can be used...which surely must increase the temperature of the compressed materials. Secondly, it uses water from the aircon, which therefore must have to be permanently on during the 99.9% of the UK year when it is not needed, thus needlessly consuming energy!
A/c isn't just about reducing temperature - it's more about reducing humidity, something we have a lot of in the UK so A/c is more useful in spring/autumn than summer - that's why mine's on all year round.
As far as I was aware, very few, if any (perhaps some of the prestige marques) have actual air conditioning - on cars, A/C is manual comfort cooling and heating, climate controlled A/C is the same but auto temperature control. As RT says, REAL air conditioning is the control of temperature AND especially humidity, inthe case in buildings via introducing steam (water vapour) or removing it via various means, as thermal comfort is affected by the relative humidity than temperature.
As such, to be able to control internal humidity and to use water for engine purposes (especially if it had to be discarded or requiring a far larger/complex condensing system), surely this would add further complexity (and thus potential sources of unreliability/failure) of the vehicles, just at the time when many manufacturers are losing shed-loads of money on fixing problems that arose from similar 'complex developments' in recent years.
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Nitpicking
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So it's used in the BMW M4 MotoGP safety car ? can't be bad then :-)
I initially thought this was for diesels but they appear to be planning to use it on petrols. Several things puzzle me:
Does it consider how wet the incoming air is - and then supply air of a constant humidity to the inlet ports ? If so, then we have another sensor in the airstream to worry about.
You only get condensation from the climate control system when it's reducing the humidity. You don't get it in dry conditions - which is just when the engine is going to need water. You're going to need to top up that water tank yourself, and make sure that you use distilled water, just like you'd get from the aircon system.
So the BMW system is going to pump all this pure water into a freeze-proof tank when you turn the car off. That's the bit where I run out of the showroom.
Water Injection has been around for many years, not been successful at all for the general public.
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Actually, that link to the MotoGP car may be significant.
The race organisers would not want the safety car to be losing ANY(*) fluids, and so BMW are faced with finding a way to get rid of it - and a simple bottle may just overfill.
(*) A bike race may be red-flagged if the marshalls see fluid on the track, assuming dry-race conditions.
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Andy - car a/c does do both jobs - cooling the incoming air condenses excess moisture which drains out of the system and the air is then warmed to required temperature by the car's engine coolant.
They may not have the fine control that buildings use, and certainly don't increase humidity in dry air - but they do control it to some extent.
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Andy - car a/c does do both jobs - cooling the incoming air condenses excess moisture which drains out of the system and the air is then warmed to required temperature by the car's engine coolant.
They may not have the fine control that buildings use, and certainly don't increase humidity in dry air - but they do control it to some extent.
I was under the impression that most cars' comfort cooling system does not actively control the relative humidity - it rises/drops as a result of wamer/cooler air being introduced into the cabin, hence why on the vast majority of cars you don't see any knob or button for relative humidity level (%). Effectively the driver has little control on what the humidity level is without seriously changing the temperature.
I suppose they (climate control systems only?) could come with an in-built humidity (high limit only - no way of introducing moisture into the system without an in-built reservoir of water) regulation system, say between 30-70% RH, which the limit most people will hapily tollerate for extended periods. Having a reservior of water would be a throw-back to the 'good ol days' of steam locomotives stopping to take on water!
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Andy - car a/c does do both jobs - cooling the incoming air condenses excess moisture which drains out of the system and the air is then warmed to required temperature by the car's engine coolant.
They may not have the fine control that buildings use, and certainly don't increase humidity in dry air - but they do control it to some extent.
I was under the impression that most cars' comfort cooling system does not actively control the relative humidity - it rises/drops as a result of wamer/cooler air being introduced into the cabin, hence why on the vast majority of cars you don't see any knob or button for relative humidity level (%). Effectively the driver has little control on what the humidity level is without seriously changing the temperature.
I suppose they (climate control systems only?) could come with an in-built humidity (high limit only - no way of introducing moisture into the system without an in-built reservoir of water) regulation system, say between 30-70% RH, which the limit most people will hapily tollerate for extended periods. Having a reservior of water would be a throw-back to the 'good ol days' of steam locomotives stopping to take on water!
Car a/c can/does reduce humidity - but can't normally increase it - in the UK's humid maritime climate that's all that's needed.
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The higher compression ratio produces higher temperatures, which are then reduced by injecting water which evaporates, thus reducing the temperature due to latent heat of evaporation.
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Didn't Tyrell use this in F1 years ago? I seem to remember it being the subject of a protest, breaking the rule about "power-boosting additives". I think the final somewhat bizarre conclusion was that it was an additive and did boost power, but was somehow NOT a "power-boosting additive"
It was nothing to do with a power boost but all about weight saving.
Tyrell spotted a loop hole in the regs that allowed you to top up fluids after a race before the car had its weight checked. So they fitted bottles of water that were supposed to be used for cooling the brakes but in reality at some point very early in the race all the water was dumped onto the track and as if by magic the car is lighter, Top up after trace and car is legal.
Had no advantage after the first race since all the other teams copied it.
Then it was banned, imagine what would happen if 24 cars all dumped a few gallons of water onto track leading into the first corner.
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