New test and tune bench for Nano turbines from www.HAB.se
Kolibri T25 (exact same engine)
2650grams / 5.84lb @ 27C / 80F
2880grams / 6.34lb @ 10C /50F
3250grams / 7.16lb @ -3C /27F
Well i can say i knew it along that jetcat is fooling with the egt probe
i measure it too
they made a big mistake in the engine , but that is something different
i can understand that the t25 is much more powerfull because of the completely different chamber , but also the much bigger impellor and turbine
Martin did a very good job , and jetcat has a basic engine
thats how i see it
congrats on the testing , very nice.
ps, i tuned the juniors
2,3 kg is not bad heeee
Regards,
Martin.
Since 'Power = thrust x exhaust gas velocity'- and we're only measuring the thrust here, that alone is not enough to say one turbine is more powerful than another.I agree the exhaust gas velocity on all jets is so fast anyway that thrust is by far the most important factor to focus on, but it's only one component when it comes to 'Power'.
Could the thrust of the T25 and P20 be increased by slightly enlarging the diameter of the exit nozzle? This would decrease the exhaust gas velocity for sure, but would the thrust then not increase too?
Well i can say i knew it along that jetcat is fooling with the egt probe
i measure it too
ps, i tuned the juniors
2,3 kg is not bad heeee
Regards,
Martin.
Well i can say i knew it along that jetcat is fooling with the egt probe
i measure it too
they made a big mistake in the engine , but that is something different
i can understand that the t25 is much more powerfull because of the completely different chamber , but also the much bigger impellor and turbine
Martin did a very good job , and jetcat has a basic engine
thats how i see it
congrats on the testing , very nice.
ps, i tuned the juniors
2,3 kg is not bad heeee
Regards,
Martin.
Since 'Power = thrust x exhaust gas velocity'- and we're only measuring the thrust here, that alone is not enough to say one turbine is more powerful than another. I agree the exhaust gas velocity on all jets is so fast anyway that thrust is by far the most important factor to focus on, but it's only one component when it comes to 'Power'.
Could the thrust of the T25 and P20 be increased by slightly enlarging the diameter of the exit nozzle? This would decrease the exhaust gas velocity for sure, but would the thrust then not increase too?
i put larger compressor in
Regards,
Martin
all the jetjoe juniors i had , had only 1,3 kg
if you raized the temp ,with closing exhaust , then you get barrely get 1,5, not more
so this is an improvement for me, and i am realy happy about it
oke, its absolutely not the a t25 , but i dont have that turbine wheel , need 2 blades[]
not much
all the jetjoe juniors i had , had only 1,3 kg
if you raized the temp ,with closing exhaust , then you get barrely get 1,5, not more
so this is an improvement for me, and i am realy happy about it
oke, its absolutely not the a t25 , but i dont have that turbine wheel , need 2 blades[]
I think it's the other way around. Smaller outlet will increase the power. Look at a fighter jet taking of, the tailcone is closed when throtteling up. I bet Frema has the correct answer :-)
A smaller diameter exhaust nozzle would cause the gasses to exit faster – i.e. the only way a fixed volume of gas can exit through a smaller aperture within the same timeframe, is if that gas is moving faster. If the power were to remain constant, then this increase in gas speed must come to the detrimental cost of thrust.
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Just like a conventional propeller, Power = Thrust x Pitch-speed. If the Power remains constant, then for the Thrust to increase (by increasing the diameter of the propellor), the Pitch-speed must decrease (by decreasing thepitch of the propellor)
Everything in a gas-turbine is probably highly-balanced/matched though, so perhaps you can’t simply increase exhaust nozzle diameter without also changing something else, but nevertheless, the principle is right. :-)
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Just like a conventional propeller, Power = Thrust x Pitch-speed. If the Power remains constant, then for the Thrust to increase (by increasing the diameter of the propellor), the Pitch-speed must decrease (by decreasing the pitch of the propellor)
A smaller diameter exhaust nozzle would cause the gasses to exit faster – i.e. the only way a fixed volume of gas can exit through a smaller aperture within the same timeframe, is if that gas is moving faster. If the power were to remain constant, then this increase in gas speed must come to the detrimental cost of thrust.
thrust equals mass flow times velocity. At same mass flow by core engine, faster exhaust means always more thrust.
Gaspar
Thrust equates to the mass of gas being displaced during a period of time (lets say 1 cubic metre per second).
But ‘Power’ is the product of this and the velocity at which that 1 cubicmetreof gas per second, is being propelled.
For example, to displace 1 cubicmetreof gas in one second through a drinking-straw requires far more power than to displace 1 cubicmetreof gas in one second through a drain-pipe, as the velocity of gas will be far higher.
In the video below, one guy is producing perhaps 80kg of thrust, but probably only 1500W of power, because thevelocityat which the gas is beingpropelledis so slow.
[youtube]http://www.youtube.com/watch?v=g3oUkyMae0c[/youtube]
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How far are you with completing your own Jets Munt nano-turbine ?
Any data available ?
I do believe you informed us at JetPower last year to come up with one having 3,5 kg of thrust ? Or did I misunderstand ?
Best,
Nicolas.
Hi Gaspar,
How far are you with completing your own Jets Munt nano-turbine ?
Any data available ?
I do believe you informed us at JetPower last year to come up with one having 3,5 kg of thrust ? Or did I misunderstand ?
Best,
Nicolas.
2:20->
[youtube]http://www.youtube.com/watch?v=vMa1USIlIic[/youtube]
Wow! 60mm and 4kg - that looks very nice! Please put my name down for one!
Wow! 60mm and 4kg - that looks very nice! Please put my name down for one!
If it happens, it would be amazing, but like you say, let's wait and see. After all, I can claim to produce a 60mm turbine which outputs 5kg of thrust... unless someone wants to actually see it ;-)
Does anyone know what would happen were you to squirt nitrous-oxide into the induction of a jet engine? Could this yield short-term gains in thrust due to the extra oxygen?<o></o>
The ECU would restrict the max RPM anyway (in this case, by lowering the pump voltage and hence the amount of fuel feed).
Suppose there would not be a set maximum (hypothetically speaking), you would perhaps have higher RPMs, but most of all, a destructive exhaust temperature, causing rear BB failure.
If your objective would be a higher RPM, I think you'd better tweak the software to do so .
Perhaps injecting small amounts of water in the compressor (hence causing perhaps steam internally and higher thrust at same RPM), would serve your theoretical objective better.
Just my 2 c, and wild guess. I am not an engineer nor turbine expert, just some logical thinking.
Nicolas.
if you only knew what i know
you can do soooooo much more with nano turbines
lots more then the factories know
We have not made the same static tests with the Kolibri and gas start as we have been flying that combo the whole summer with no problems.
Video will be up soon.
More testing useing FLIR later during the hollidays.
Sorry for posting here, but this great threads seems to be accumulating some knowledgeable miniature turbine folk. :-)
My P20-SX has been out-of-action for a couple of weeks, as by accident I plugged a 4S (14.4V) battery into the ECU instead of the correct 2S (7.4V) battery. The ECU went bang (there was smoke!) and that was that. :-(One of the consequences after I blew-up the ECU, was that if you tried to power it up again, the starter motor would just spin without being instructed to by the transmitter.
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I sent the ECU back to JetCat and they repaired/replaced it reporting that the PSU element had been fried. With the new/repaired ECU they returned however, although my P20-SX now trys to start normally, it fails with a “LOW RPM”. Please see the video below, it seems like either the RPM sensor is faulty, or the logic in the ECU which reads the RPM is faulty?<o></o>
Does anyone have any suggestions what I should check?
[youtube]http://www.youtube.com/watch?v=hARHQ_iuHy8[/youtube]
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your starter is slipping
yo need to clean the oring or put new one in
Regards,
Martin.
Make use to wait a good 15min before starting the engine so that the break cleaner evaporizes, else dooms day