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Water Injection for Industrial V-Twins

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karmarepair

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...has been suggested for cooling at high power levels.

Have you done it?
How would you do it?
I have my thoughts, after researching it a bit, but I'm wonder what the GroupMind thinks.
 

stanislavz

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has been suggested for cooling at high power levels.
In car world it is ok to spray some water on radiator (especially inter-cooler) for better cooling effect. I would suggest to spray it on head, near exhaust valve.

Water injection is no win for low compression/no turbo issues - it is for internal mix cooling to avoid detonation.
 

soupercooper

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Ive installed water injection in my supercharger system on my Shelby mustang its a pretty simple system, i also add methanol to the distilled water to increase octane level as well. water injection was invented in WWII for supercharged aircraft to get to higher altitudes. it also cleans combustion system of carbon and reduces EGT and CHT temps. . im sure you could research the products from the automotive industry, but you need to look at direct port injection option instead of boosted application.


three companies that come to mind are snow performance products, AEM and devils own, i use devils own products but if done it over again I use snow or AEM and i use the simpler System of using a Hobbs switch, but they have computer controlled units as well. but been mostly used for boosted applications and I believe you need direct injection Option application or naturally aspirated option, go to their websites and check it out, cool stuff, BMW is now using water injection, technology been around like I said since WWII but hasn't really taken off for automotive until recent years. the pumps are high pressure (300 psi or thereabouts) though and may pull some hefty current/amperage though?

 

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stanislavz

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Water/methanol injection was meant for internal air-fuel mixture cooling to allow bigger boost level. But not to decrease necessary external cooling.
 

soupercooper

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Water/methanol injection was meant for internal air-fuel mixture cooling to allow bigger boost level. But not to decrease necessary external cooling.
I dont think the author meant for external cooling but for internal? Ive never heard of external water injection? or spraying? Im sure its been done but again I think he meant internal injection application.
 

soupercooper

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there is now kits for not just for boosted engines but now for Naturally aspirated EFI and direct injection engines but dont know if good for carbureted engines?, I did see though a carb spacer with injection nozzles on one companies website so maybe rare but possible to use for carb engine.
water or water/meth injection are not just for boosted engines anymore, look at the top link I shared above that's exclusively for naturally aspirated EFI engines, you can get the Industrial v-twin engines with EFI so I say the possibilities are there, but is it worth it for this application is the best question to ask. again I have installed and designed water injection systems on muscle cars but for boosted applications but there are other benefits as well for non-boosted engines, there is a ton of info on this, go to snow performance for the best explanation of all this as they can explain it better than I can or want to.
 

pictsidhe

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Water injection has mostly been used to suppress detonation. IIRC, injecting equal parts water and fuel raises effective octane 8 points. There's a paper out there I calculated this from. That isn't this threads topic, though.

I first thought of using water to aid air cooled engine cooling at high power levels some years ago. It didn't take me long to find three papers on the subject. Here's one.
"Based on this work, several pertinent recommendations have been made: (1) utilize water
injection for short-duration, very high-output operation which would otherwise be destructive
due to thermal overload"
Yep, exactly what I had in mind! This particular study was done on diesel engines to investigate total cooling from water injection. Port injection was found to need a 3.36 ratio of water to fuel for complete engine cooling. The actual numbers will vary a bit for SI. As a guess, we may need 4:1 for complete cooling.

Now, if I'm hosing in water at high power levels, I might as well take advantage of the effective octane boost as well and raise the compression. I'll have a more efficient engine at part throttle cruise that doesn't need water. A more powerful engine at full throttle, that does need water. Other than added complexity, it's all win. The injected water substitutes for the rich mixture traditionally used, so offsets the system weight.

I'm wondering if I could make a water 'carb'. It may be hard getting a fine enough spray.

Meth/water could be used too, but then it becomes fuel, which complicates dosing. It's going to be far harder to top up with meth/water at the average airfield. Water tends to easier to find than fuel...
 

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Hot Wings

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Have you done it?
<< >>
How would you do it?
Direct spray cooling on an industrial engine - Yes. Decades ago when I modified the family B+S lawn mower to run on model airplane fuel*. It worked. I'm just lucky I didn't loose a couple of feet.
Water into the intake - on several engines over the years. It is treuly amazing just how much water you can dump through a Mopar 361 without getting hydraulic lock. Did it work as intended on any of them? Don't really know. I didn't do any testing. I do know the spark plugs stayed cleaner.
<< >>
How would I do it on an industrial engine?
Simple way is with simple switches. Head temp/throttle position/manual. If you don't have objections to little black boxes then let the electrons do the deciding. Water/alcohol in the intake being the first add. Having to resort to external cooling - to me - indicates the engine is being pushed too hard for normal aviation use.
A basic windshield washer pump is all we need for the industrial engines. In the early days (when having a windshield washer was an add in the sales brochure) we could buy add on systems that came with the pump and tank.

*Had little problem getting nitro-methane and denatured alcohol back then. Getting castor oil to mix my own for the models was actually a problem - for me. The world has changed.......
 

stanislavz

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"Based on this work, several pertinent recommendations have been made: (1) utilize water
injection for short-duration, very high-output operation which would otherwise be destructive
due to thermal overload"
Yep, exactly what I had in mind! This particular study was done on diesel engines to investigate total cooling from water injection. Port injection was found to need a 3.36 ratio of water to fuel for complete engine cooling. The actual numbers will vary a bit from SI.
Thank you for article. My sorry - yes, you are able to coll engine with injected water only.. But ratio is on extreme side, and you have to able to spray it directly on heated parts.. + proper timing..
 

pictsidhe

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Thank you for article. My sorry - yes, you are able to coll engine with injected water only.. But ratio is on extreme side, and you have to able to spray it directly on heated parts.. + proper timing..
That study was for complete cooling. Once you run out of air cooling, you need a plan B. 50% more power than your engine can happily dissipate is going need about 1.33 as much water as fuel. At 25%, about 0.8:1. It does not have to be directed at any part. It can be simply added to induction air.

With sprayed water, if we get 100% heat to evaporate from the engine, the ratio is about 2.7 water to fuel. That probably lends itself better to intermittent use, but directing the water where needed could be tricky. If you spray water into the cooling air intake, at least some water will not hit the engine and be wasted. You may well end up with very similar water use compared to direct injection, but without the side benefits to combustion. Both systems have their pros and cons, both will work. Take your pick and experiment! Even better, try both! A pair of spray nozzles could be tested in the induction air and in the fan.
Another alternative on engines like my Briggs is to partially weld up the passage under the rockers. Add a thermocouple and flow water in to keep temp a little above boiling point. You would need to use distilled water.

Edit, fixed numerical error.
 
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soupercooper

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Snow performance has a water injection digital control unit that works with the EFI mapping (ECU) to control the water injection so maybe a good candidate for the EFI version of kohler engine which use Delphi EFI ECU unit. Carb version engines maybe more challenging to install water injection system? Im sure other members have touched base on this already and I will read their comments.

Using a windshield washer pump already integrated in a water tank is a good idea to consider as stated by member Hot Wings. I didnt think that pump put out enough pressure? typically on automotive application they use 300 psi (capable) diaphragm pumps. that would be awesome if windshield pump would be suffice! on my cars I use the existing washer fluid tank and convert it to my water/meth tank but I bypass the windshield washer pump and use the diaphragm pump that comes in the kit. nozzles are very small orifices and of course pump pressure is defined by orifice size of nozzle, Im guessing you need at least 60+ psi for these nozzles, its just a guess as I dont have a pressure gauge on my system but I think thats what I read once on the websites of these products.
 
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pictsidhe

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An ECU controlled water injection is going to need its own ECU output. That rules out stock ECUs. Some systems measure injector pulse length and inject accordingly.
We only need water at fairly high induction velocities. I will be playing with simple 'carbs'. I don't like the weight of the car water systems.
 

stanislavz

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Idea - our most heat strssed area is exhaust. I would bet on internal injector to spray only at exhaust cycle. Hence quite low pressure.
 

soupercooper

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An ECU controlled water injection is going to need its own ECU output. That rules out stock ECUs. Some systems measure injector pulse length and inject accordingly.
We only need water at fairly high induction velocities. I will be playing with simple 'carbs'. I don't like the weight of the car water systems.
Excerpt below from the EFI system controller from Snow products as I already posted this link but I guess some folks just dont read any of it and geared up to just be nay-sayers ALSO Im using automotive kits for reference only as its OBVIOUSLY too heavy for aircraft application, at least the pump is and Hot Wings had a suggestion to use windshield water pump as a viable option if it can produce enough pressure.
Im seriously done butting heads with always one particular member. I gave my 2 cents worth...
I will lets you guys have at it. I avoid pessimistic folks.

Snow Performance states...
The Stage 3 Boost Cooler® is unmatched for accuracy and adjustability in water-methanol injection systems! This system can be used on any engine with a traditional EFI (electronic fuel injection) system, and features our LCD display with on-the-fly adjustability. The Stage 3 DI creates a injection map based off the gasoline fuel injector pulse width (and optionally boost pressure when used in a turbo- or supercharged engine).

Extremely easy to set up and dial in - the software creates a delivery map based on boost and/or EFI signal from just a few easy to set points you punch in from the drivers seat. The LCD Screen displays boost pressure, fuel injector duty cycle, as well as water-methanol injection percent. Quick, easy, positive adjustments are made with 2 push buttons. Low profile design allows for easy-to-view and discrete mounting. Note: The EFI-System can´t be used in direct injected engines.
 

Hot Wings

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The washer pumps I used are pretty low pressure. Never bothered to measure them but I'm guessing well under 20 psi. I just fiddled with the stock sprayers scavanged from various systems to get the mist as fine as I could and simply pointed them at the carb opening depending on the intake turbulence to further atomize the spray.

If we want to do timed injection of the water/OH then I have little real world experience to offer.

I remember reading a paper on the best droplet size for cooling. Been a long time and I don't remember ANY of the details but for intermittent use, like 5 minute TO power, I guessing that the droplet size is secondary to just getting enough H2O/OH in. Who cares if we need 100% more to get the job done? Even at a coolant/fuel ratio of 2 that isn't much cooling fluid. - even for a part 103?

I could be wrong about the quantity needed. I remember? my father telling me that the WEP tank on the P-51s he worked on carried around 50 gallons of H2O/OH. To me that seems like a lot of fluid to be dumped into a Packard/Merlin in 5 minutes. My garden hose/ Mopar 361 experiments were a result of that bit of trivia.:rolleyes:
 

pictsidhe

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Soupercooper: Pessimistic? Haven't I been the main HBA proponent of this idea? I'm looking for something that will work, and doesn't weigh or cost too much. I've also probably done more research on this than the rest of you here. If you had read some of that, you'd also know that an ADI system isn't optimal for us, but could be adapted or have parts used. Please forgive me for trying to share some of what I have learned.

You said the Snow system was ECU controlled, not controlled by the injector signal.

Welcome to the list.
 

pictsidhe

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I've measured up to 40psi on washer pumps. Headlight washer pumps are apparently even better. Regulating flow by line pressure causes a big variance in droplet size. If I can't get my carb idea to work, I will likely try multiple nozzles controlled by small solenoid valves. 3 valves would give 7:1 turn down ratio, 2 valves 3:1. That's without affecting droplet size.

I think the paper on the effect of droplet size was by the same authors as the one I already posted. It's been a few years. IIRC, they found droplet size larger than optimum for ADI is better for internal cooling. The droplets are more likely to splatter on surfaces, to evaporate during the latter part of the exhaust stroke. Where they are most beneficial.
 
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