Testing My JET ENGINE'S Water Injection System!

[@theplayonier7791]

Ive always wondered what a water injection system would do to a turbo-barrel setup. Looking forward to building one with my frieds this summer. Amazing channel ive stumbled into, keep up the great work!. Got here from yt shorts

[@eg_engineeringaustralia]

@theplayonier7791 I always love seeing a wild turbo-barrel so let me know how you go, be careful though they don't exactly have an off button 🤣 Thanks for the comments, I'm really happy to hear that others are interested in this sort of stuff!

[@johnwick9935]

First time here, subscribed!

[@eg_engineeringaustralia]

@johnwick9935 Thank you!!

[@hunnybunnysheavymetalmusic6542]

Very thought provoking! I've never thought of using water injection this way, but it definitely rings similar to water injection on reciprocating engines. I personally never thought of bleeding boost for side projects either. I've used it for cooling purposes, but that ended up still pushing the boost overflow back into the exhaust of the engine in my case.

[@eg_engineeringaustralia]

@hunnybunnysheavymetalmusic6542 haha yeah it's opened a lot of avenues for auxillary projects! I've got a bunch of things I'd like to test. Thanks for the comment - let me know how you go with your engines 😊

[@shawnrinkel8377]

Hell yea!! This is awesome and a question I have always had!

[@eg_engineeringaustralia]

@shawnrinkel8377 thanks mate! yeah I still have a few more questions that need answering haha but that can be next weeks testing!

[@flack3]

Nice stuff!! Ill be waiting for more

[@eg_engineeringaustralia]

@flack3 thanks a lot mate - been making plenty of changes this weekend, so after next weekend I'll have some new testing videos ☺️

[@Gin-ging]

not sure if you tried in an older video but if you added a bell-mouth to the compressor inlet you can gain some flow and efficiency, not sure the exact numbers but on a turbo for an engine it can be upwards of 10%

[@eg_engineeringaustralia]

@Gin-ging Thanks for the comment! I haven't used one before but they are a good idea - I'll have a look around and see if i can find one for a reasonable price to suit my turbo. Tbh I was considering making a muffler kind of inlet just to reduce the screaming a little for my neighbourhoods sake 🤣

[@jonmeacock8267]

fantastic work!!

[@eg_engineeringaustralia]

@@jonmeacock8267 thanks!

[@tsclly2377]

Add a bit of alcohol to the water to change the character of the liquid as to increase vaporization (I believe as little as 2% will do). Alcohol can add a bit of energy as fuel at a lower temperature combustion rate and add to lower temperature use (50-50% will keep the solution from freezing to around -25*C(+)..a(and it can be used as a after burner fuel).

[@eg_engineeringaustralia]

@tsclly2377 Thanks for the comment! Great idea for sure, I've read a lot about water / alcohol injection but am yet to test it - definitely on the list of things to explore so thanks a lot for the info! Vaporisation has proved challenging with such a low pressure pump, my plan was to go with higher pressure but alcohol might be worth trying before I upgrade down the track 😊

[@turkeyboyjh1]

@@eg_engineeringaustralia use a water methanol injection pump and nozzles

[@eg_engineeringaustralia]

@turkeyboyjh1 I'll do some testing first as that'll still cost a fair bit, for context, the current pump was like $35 haha

[@turkeyboyjh1]

@ oh yeah I never said they were cheap but they work very well

[@daviddroescher]

Most water meth injection systems companies are using 12dc RV fresh water supply pumps at 60psi like what you have . There is 1 company that I know of that has developed a 1000psi system pump, lines ( your hard lines are sufficient ), jets, and flow rate calculations. There name is RB racing , devloped for 1200cc to 600+cid motors at Bonneville salt flats My thoughts are; 1) the finer the mist the faster the evaporation .2) The higher the pressure drop the colder the water going in will be. 3) at some point as pressure increases explosive decompression will start to factor into ( like a coak a cola) .evaporation rate/ droplet size. Around 400usd gets you a bldc 3kpsi pressure washer as a pump at home depot.

[@sebbes333]

*@EG Engineering Australia* I actually think you get more power out of this 7:57 water, instead of this 2:11 system. Because now that water gets into the primary zone and gets a chance to boil to steam, and steam increases the volume MANY times (about 1'700x volume at sea-pressure), instead of as you said 5:54 that the water have no time to boil when in the dilution zone. 🤔 If you can pre-heat the water by using it as a coolant for some part of the engine before injection, it needs less energy to boil to steam, energy gained from otherwise waste-heat :D

[@eg_engineeringaustralia]

@sebbes333 thanks for sharing this, i definielty agree with your logic mate, and the benefits of wet compression like that at 2:11 are very well documented but there's a couple reasons why I'm avoiding it (for now). It seems to be more limited with flow compared to internal injection, and I need to be able to inject several LPM for my aux combustor project. I didn't measure the example at 2:11 but it wouldn't have even been 1/10 of that just for perspective. I'm sure you can do it, and I'd like to test again in the future but for now I want to give internal a proper crack. Second reason is, injecting at the inlet alters the composition of air entering the auxillary combustor which will mess up some of my future plans with the engine. Blade errosion (both comp and turbine) is another consideration but honestly it's going to happen no matter how I do this with these flow rates so it's just something that i will need to keep an eye on via inspection. Hope that helps and thanks for the informative comment 😊

[@sebbes333]

@@eg_engineeringaustralia Hmm... Blade erosion is something I haven't considered, but it's obvious when you mention it, the blades rotates at what? several 1k RPM? So throwing water, in there (even tiny mist droplets) would be similar to throwing sand into it but at lower RPM? that's not so good. It reminds me like the opposite of "cavitation bubbles" (vacuum bubbles collapsing) that fast water propellers gets eroded from.

[@eg_engineeringaustralia]

@sebbes333 the max for this turbo is 105,000RPM hahah so yeah it can be a serious problem. I'm fully expecting to need todo turbo rebuilds in the future if the blades erode but thankfully it's a very common turbo and I can get it done through a company here cheaply because they go through them like crazy. There's plenty of ways to reduce it, and tbh a lot of comments on here are on the money with suggestions, it's just a matter of what's cost and time effective to implement. My priority is testing the new CD nozzles with the current setup as people keep asking for more shock diamond videos haha but after that I'll revist the water system. I'm really glad that so many people have been interested in the technical side of this project it's great to connect and brainstorm ideas 😊

[@watt1241]

You can try to make superheat steam from exhaust heat injection, break down water's molecule. Better than atomizing droplet.

[@eg_engineeringaustralia]

@watt1241 thanks for the comment! I'm assuming you mean regeneration? Like heating the water through tubes in the exhaust to a steam and injecting the steam in to the combustor? If so I have thought about it but it's a lot more to consider than just pressure Injection of water. Definielty agree that it's more effective / efficient though 👌

[@TheBillzilla]

FWIW water injection on jets is normally placed with the nozzles in front of the compressor. You need to get the atomisation as good as possible as the droplets tend to wear down the leading edges of the blades a bit.

[@eg_engineeringaustralia]

@TheBillzilla Thanks for the comment mate! Wet compression like you're suggesting is very good for increasing power, but my main goal herr is to reduce TIT when I'm bleeding air off of the compressor for my auxillary combustor, and injection into the main combustor can achieve this while not affecting the composition of fluids going to the aux combustor which would be the case with inlet injection. I need todo a lot more R&D on this topic to find what works best so I'll likely revist inlet injection in the future ☺️

[@TheBillzilla]

@@eg_engineeringaustralia Sure, but injecting water in front of the compressor will also help reduce the TIT. I've got a couple of thousand hours on Metro 2's & 3's, and we use water/methanol injection on those to boost power for hot take-offs. The amount of boost the water/meth gave depended on how much the pump was turned up, the best I ever saw was on a TPE-331-10 in a Metro 2 (VH-UZY) and when you hit the pump the torque would go from 800 lb-ft up to 1,500 lb-ft! Then very careful tweaking of the throttles to get the torque up to the 2,200 lb-ft limit. You'd never be temp limited that way. Also FWIW when using just plain water they wouldn't make a lot more power, but the turbine temps would certainly drop. The reason being that as the droplets when through the compressor they'd phase change to vapour and that'd absorb a fair bit of heat.

[@neil_neil_orangepeel]

Nice build! I would be keen to see more detail on how your combustor is built... looks well thought out. What was the theoretical temp drop you were expecting based on the water rate? Just a suggestion if you arent getting the expected drop but it seems the vaporisation might be better if the water was introduced before the dilution air where the gas is hottest. Also some internal vanes or some other structure after the sprays to induce turbulence and help the water droplets break up might assist.

[@eg_engineeringaustralia]

@neil_neil_orangepeel thanks a lot for the comment mate! Take a look at my instagram if you have it (same name as my youtube), I've put up plenty of images a while back that show the inside of the combustor. I'll eventually do a video designing and machining a new main fuel nozzle which would be a good video to run through the flametube design etc but that might be some time away as my focus is this auxillary combustor for now haha. The temp drop is ballpark what I expected from just 3lpm but I'll need even more than that, so I'm going to bump up the pressure and also add the 4th nozzle in the primary zone. It's all a bit of R&D at the moment as I find out what works best 😊

[@daviddroescher]

you are running post combustion , equivalent to spraying in the manifold ( after valve before turbo) for a gas/diesel engine. My thoughts for an expairament of my own , using pre and post cylinder injection on my diesel. Pre reduces Altitude Density( higher lb per cubic ft) and in cylinder steam generation/expansion. Post to recover lost volume from 1st stage exhaust turbine contraction , yealding higher pressure raito in 2nd larger turbine housing that force feeds the 1st more lbs per min . Dream Big Chisel Down to Really

[@fishyerik]

Interesting subject! Could one of those spray systems for general evaporative cooling by misting that have a pump to increase the water pressure to significantly higher than ordinary tap water pressure to generate really fine mists also work? Not that I'm an expert, but I've heard that working on the sound quality can make a big difference for how popular videos/channels get, for comparatively little effort. Maybe you want to look into how to decrease reverberation/echo when you speak indoors. And maybe explain the benefits of water injection a bit more, on a basic level.

[@eg_engineeringaustralia]

@fishyerik Thanks heaps for this comment mate, really makes it all worth it! The purpose built misting systems would absolutely be better, and even better again are high pressure fogging nozzles. I actually have a very high pressure spray system (10,000PSI), that i used to use for the kerosene injection, but for the purpose of the video I just scraped together some stuff that was laying around and easy to chuck together. Regarding the internal spray stuff, I'll definitely upgrade this to a 1000psi system in the future but this was just a cheap easy way with mostly stuff I already had. I need todo a lot more R&D with the water injection before I go investing in a proper system. Hope that helps! Regarding audio, that's a great call and I'll definitely work on it for future videos, thanks again for the comment it means a lot ☺️

[@sterlingarcher813]

7:10 maybe give a regular car fuel injector a go probably want one for a big v8 or a semi truck so you have plenty of mass flow rate

[@eg_engineeringaustralia]

@sterlingarcher813 hahah Sterling, my man, huge fan 😂 thanks for the comment, I think I'll get some fogging / misting nozzles for next time I do this but the problem is pressure and the air assisted nozzles alleviate that issue. Pumps are expensive haha

[@ThiagoMarquardt]

Very nice! Steam in gas turbine!

[@eg_engineeringaustralia]

@@ThiagoMarquardt that's the goal! 😊

[@adamgaffer3991]

I'd love to see you run the jet on alternative fuels

[@eg_engineeringaustralia]

@adamgaffer3991 this jet was originally made as a platform for alternative fuel testing as part of my engineering thesis project! There's some other videos on the channel of it running both simultaneously and individually on kerosene and LPG, which I did for emissions analysis 😊

[@adamgaffer3991]

@eg_engineeringaustralia sweet I came into the series a little late but what about waste oils or bio diesel

[@eg_engineeringaustralia]

@adamgaffer3991 The videos are pretty old haha I did the project back in 2020 actually. The focus was on dual fuel with methane or hydrogen being combusted simultaneously with jet fuel. But, you can fun jet engines on just about anything combustible you just need to atomise it. Heavy oils could still work but you'd need to use an air assisted atomisation nozzle

[@Sir-Dexter]

nice work

[@eg_engineeringaustralia]

@@Sir-Dexter thanks!

[@ZachSwena]

Shouldn't you inject later in the combustion process? I would think that the heat absorbed by the vaporization could inhibit complete combustion if set up wrong...

[@eg_engineeringaustralia]

@ZachSwena it definitely can, and I'm absolutely expecting it to happen with this basic primary zone injector but the part that I left out of the video was I already had the holes there's from previous stuff so it was very easy to add and I just want todo some tests as more of a sensitivity analysis more than anything. It would likely be better to inject just after the primary zone so you don't disturb combustion as much like you said but we'll see 😊

[@buxybuilt1519]

Love it mate! What state are you in? I don’t know how you’re able to start this up with neighbours right next to you. If I started mine up I’d have the cops at my door within 5 mins

[@eg_engineeringaustralia]

@buxybuilt1519 SA haha! I've got 2 empty blocks next to me and commercial buildings behind me and I only do short runs on weekends. I am looking for an industrial location for longer tests runs. Limited run time is by far my biggest hurdle for progress with this entire project though

[@buxybuilt1519]

@ ahh ok I’m in Perth, you can see the contraption I’ve made on my channel, have since gone 160km/h with it. But yeh same problem, I have to drive out where there’s no one for miles to run it. The afterburner can be heard from a long way away. Your build looks very professional. Will keep an eye out on your channel for more updates 👌🏻

[@eg_engineeringaustralia]

@buxybuilt1519 looks great! that would great fun but yeah the afterburners are crazy loud, I was designing one for my engine to run on my old kero system but nowhere to test the damn thing 😅

[@bareMinimumExample]

how about putting 2 or 3 in series for increased pressure and hopefully efficiency. and intercooler between each stage

[@eg_engineeringaustralia]

@bareMinimumExample 🤫 that's on the list of things todo haha

[@hardbackbreaker567]

is it possible to drive another turbo from the first outlet and get the compressed air from that?

[@eg_engineeringaustralia]

@hardbackbreaker567 take a look at compound turbo setups - little different to what you're describing but they do offer some interesting benefits 😊

[@paulthepilot5]

Any idea what percentage of the mass flow are you bleeding off the compressor for the second combustion chamber?

[@eg_engineeringaustralia]

@paulthepilot5 depends on the throat area of the nozzle that I'm using, I've started small (around 15%) but plan to work my way up with larger nozzles and just keep an eye on temps 😊

[@paulthepilot5]

@@eg_engineeringaustralia interested to see how it goes. I’m in the planning stages of an HX85 based turbine and a bleed air generator for turbo/supercharging system on an engine. Never had considered water or Water/meth injection to compensate for the bleed air losses

[@eg_engineeringaustralia]

@paulthepilot5 yeah it's a unique concept, I still have a lot of r&d testing todo to improve it though.. Let me know how you go with your project, sounds like it'll be an interesting one! 😊

[@laser69beam]

Why not add a second turbo…? Current setup as is, just pipe the final exhaust through a second turbo and use that fresh air for the nozzle testing

[@eg_engineeringaustralia]

@laser69beam thanks for the comment mate and really good thinking, but there's some major drawbacks to consider. firstly you need to buy a turbo, which even second hand in 75mm size is expensive.. and the big one is that the second turbo wouldn't get anywhere near the pressure of the first one due to the horribly inefficient turbines which basically all turbochargers have by desing. Compound setups are a slighty different story and something I am keen to test in the future but there are similar considerations to be made. Hope that helps 😊

[@Emprivan]

Maybe add a little methanol to the water.

[@eg_engineeringaustralia]

@Emprivan this is just a temporary setup for testing so I'm running straight from a hose. I'll have to add a tank so I can filter water easily and can add alcohol or methanol for testing down the track but this should be fine for now 😊

[@ThiagoMarquardt]

And ethanol injection?

[@eg_engineeringaustralia]

@ThiagoMarquardt im going to stick with water for now but alcohols would help