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Post by Johansson on May 13, 2017 15:58:55 GMT -5
Since I am not very interested in the Eurovision finals I spent an hour modifying the fan instead. I removed the curvic coupling from the fan and cut the bore cylindrical so I can fit a centrum hub with a 25mm bore and a keyway slot. The angle grinder might not be everyones tool of choice when modifying gas turbine rotors, but it is darn handy. Almost there... And it is done! When I have made and fitted the new fan hub I can mount the fan to a dummy shaft and true the angle grider cut edge in the lathe. Cheers! /Anders
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Post by Johansson on May 12, 2017 15:28:24 GMT -5
Aha, interesting! Innovative as always! Keep up the good work! The venturi injection was Johns idea, clever as always.
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Post by Johansson on May 12, 2017 15:16:44 GMT -5
Still trying to figure out how it all will fit together with the fan.... Nice work Anders! I saw somewhere that the fuel flow to the EBK was calculated to 30liters/minute. Have any plan yet on what pumps to use? 10pc of biltemas finest Bosch 044 copy? No pumps at all will be used, we will either pressurize the fuel tank with P2 air or make a venturi injector upstream the fan so that it sucks the fuel by itself.
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Post by Johansson on May 12, 2017 14:31:41 GMT -5
Thanks guys!
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Post by Johansson on May 12, 2017 12:38:33 GMT -5
I spent last night working on the turbofan, first up was to make a ss2333 stainless bushing to fit the turbine wheel with 30mm bore on the 25mm drive shaft. A snug push fit, perfect! The bushing fitted to the turbine wheel, this surface will push against the rear bearing inner race. Something I have been thinking a lot about is how to couple the NGV to the shaft tunnel, my first idea was some kind of bolt circle with countersunk and wire locked screws but the lack of space made this almost impossible to machine. While standing there scratching my head I suddenly realized that I could make a threaded coupling in the lathe! The shaft tunnel threaded. The matching nut that is going to be welded to the NGV. Both parts finished, but will they fit? Oh yes they do. Here the exhaust manifold is placed over the NGV, next up is to turn the inside of the shaft tunnel to a snug fit for the bearings. Cheers! /Anders
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Post by Johansson on May 11, 2017 17:00:46 GMT -5
It certainly will be interesting to see what the water does to the overall performance. I'll be following. Increase fuel flow along with the water to stay withing temperature limits and potentially end up with more power. It sure will! I´ve read the statement here and there that "increasing fuel flow will raise temperatures and give more thrust", sure it will but as the engine they refer to is already running at 100% of the design RPM (why wouldn´t it?) I don´t understand how pumping even more fuel into that engine can be considered a wise idea. Or will RPM drop when water is injected and adding fuel is a way to compensate for that loss and get the engine up to 100% again? Cheers! /Anders
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Post by Johansson on May 10, 2017 11:57:58 GMT -5
I am keeping my fingers crossed for you!
Just remember to video tape the run, video footage of the engine and the gauges is very valuable to have. I keep looking at my old test bench videos for reference when I have done a new bike test.
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Post by Johansson on May 9, 2017 22:56:16 GMT -5
Progressing steadily :-) I rather envy you guys having someone to sit and "talk crap" with about a build, my shed is rather empty of laughter . 200 kph+ should be easily achieved , Olov might need some "aero controls" for steering and stability at its full potential ;-) Cheers John Hi John, Actually meeting up was a rare occation, 99 evenings out of 100 we are working on our own with a weekly lunch time phone call if we need to discuss anything. We Swedes are a solitary breed, or at least I hope so since the alternative would be that Olov and I are social misfits. Cheers! /Anders
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Post by Johansson on May 9, 2017 16:48:46 GMT -5
That is great of him, always good to have an expert check in on things when you are stuck. I would know since I must have emailed you a thousand times about my engine problems...
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Post by Johansson on May 9, 2017 16:43:38 GMT -5
It will be a tight fit to get everything packed in there in a service friendly manner, making a snakes nest of glowing hot exhaust ducting around the whole engine would make heat shielding a nightmare... We´ll try to make the exhaust as flow friendly as possible, as it will exit on top of the fairings I think that the air passing by at 200+km/h will help evacuating the exhaust gasses. Olov and I was throwing ideas around after work today and couldn´t keep from giggling like two school girls, this will be a fun ride for sure! Cheers! /Anders
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Post by Johansson on May 9, 2017 16:22:59 GMT -5
After thinking it through I´ve decided to make the bike ready to race with water injection and try to get at least one good run out of it at the One Mile race this year, as long as the engine is in running condition I will keep racing it while sorting out JU-02 but if something more serious happens I´ll retire it. I spend an evening tonight rerouting the scavenge oil lines to make the suction line between the engine and pump as short as possible, it was tricky to fit everything but I finally figured out a position that worked and was rewarded with a pump that sounds to struggle a bit less. I also removed the gas producer from the bike to check the turbine and freepower NGV, nothing seemed damaged so that was a relief. I was a bit worried knowing how hot it was after the run with the oil leak... Finally I connected the water injection pump through a relay with the throttle grip micro switch providing the signal, now I can set a high idle around 1 bar with the throttle module potentiometer and as soon as I touch the throttle at the starting line the water injection starts. The signal will be routed through an existing P2 pressure switch so that the water injection cannot be accidentally started when the engine isn´t running. Before I can start the bike again Olov will reprogram the throttle module since the idle potentiometer range is set too low, at its max setting the engine just barely reaches idle revs so that needs to be upped a bit. It will be very interesting to find out how the water will affect things! Cheers! /Anders
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Post by Johansson on May 9, 2017 0:31:56 GMT -5
Hi guys,
Looking at yesterdays video with fresh eyes the temps were bad but not terribly bad, for some reason the engine use to run hot up to 1bar where it drops down to more normal levels. At the end of start no.2 there was a small drop in temps when I passed 1bar so it might be the non-spinning freepower that upsets the temperatures a bit.
Perhaps I should keep it as it is and try the engine again with water injection just as Mark suggested, if the temps drops just a tad I´ll tie up the loose ends on the bike and save it for One Mile at the end of the summer.
I really need to start focusing on the turbofan if we want to have it running next winter, so racing the bike as it is this year and start the JU-02 development when the turbofan is finished sounds like a good compromise.
Cheers! /Anders
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Post by Johansson on May 8, 2017 16:08:59 GMT -5
Hi Anders, I'm a keen fan of this thread! It seems that the high temps readings are not accompanied by physical signs of heat damage internally. Are you confident that there is no electrical interference. Have you tried an external temp sensor that is isolated from the bikes electrical system. Is an IR gun an option? Keep up the good work. George Hi George! It might very well be as you say that there is some kind of interference messing with the readings. The thing is that I have been fault finding the temps in JU-01 for the last 5 years or so with very limited success, and I am actually worried that I will get tired of the whole bike project if I don´t move on to the new engine soon. Hopefully I will get me some new and interesting problems to sort out with JU-02. Cheers! /Anders
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Post by Johansson on May 8, 2017 14:49:21 GMT -5
I see two ways ahead right now.
1. I keep working on JU-01 trying to figure out the issues and if I succeed I might be able to add a handful of km/h's to the 284 I ran last year if I push it hard.
2. I decide to set JU-01 aside and spend my time getting JU-02 running in the test rig instead, I need the bike systems for the testing so it won't be doing any racing until JU-02 is installed in it.
If I go for no.2 I will of course get JU-01 sorted out in the test rig once JU-02 is in the bike, no way I am giving up on it but it is starting to feel like I am spending a hell of a lot of time on an engine that at the end of the day is to weak to give the bike the kind of speeds I want.
I know what I am voting for, but I'd still like to hear what you guys think. It is a pretty big decision after all.
Cheers! /Anders
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Post by Johansson on May 8, 2017 13:48:31 GMT -5
The strange thing is that during the first test run I had a temp of 700°C when I held the engine at 1 bar, but when I held it at the same P2 during the second test run the TOT is suddenly stable at 800°C. How in the holy Moses name can this happen??
Looking at last years One Mile video of the dashboard I can see the same temp rise, perhaps I should try to get the bike tested with the freepower spinning before I draw any conclusions?
Cheers! /Anders
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