bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jun 23, 2017 12:35:43 GMT -5
Hi John, Sorry for my late reply on this. Concerning the compressor wheel, What I'm looking to make is a compressor for 350pounds output: My latest drawing board work gives: 7.1 exducer 5.6 inducer(inches) 1.1 inch hub I put in the values to jet specs and I get: 46,805 max rpm.
What can you suggest please Thanks in advance Sorry for my late reply Cheers, bournaVee
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Post by racket on Jun 23, 2017 17:34:27 GMT -5
Hi BournaVee Theres problems with your dimensions , the hub will need to be bigger than 1.1" simply for strength reasons , this will then require your inducer and exducer to increase in size . With a 5.6" inducer your inflow speeds will need to be very high to achieve your desired thrust level , this combined with the rather high Trim number for the wheel will start to produce "sonic"problems despite your relatively low exducer tip speed , the "lowish" tip speed will produce modest Pressure Ratios, which in turn will produce less thrust per pound of mass flow , which in turn means more inflow area required , lets use our TV94 comp wheel as an example , it has ~11.7 sq inches of inducer area and an engine using it will produce ~120 lbs of thrust , so ~10 lbs of thrust per sq inch , your 350 lbs of thrust will need 35 sq ins , this then means a 6.6 inch inducer diameter, and with a relatively large 56 Trim, an exducer of ~8.8" , in a casing of ~14 inches .....LOL, sounding very much like my Skuld dimensions ;-) For such a large thrust level the costs in both time and money when making your own bits will become prohibitive , it would be more prudent to use some commercially produced parts as I tried with my SKULD engine jetandturbineowners.proboards.com/thread/371/skuld-666 but even when using such parts , the job becomes "troublesome" :-( There are large turbocharger bits form locomotive turbos that could be used for the thrust levels you are looking at producing Cheers John
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jun 24, 2017 4:56:36 GMT -5
Hi John, Thanks for that. I get what you are saying..not to mention irregularities that might come with the design. What locomotive turbocharger rotor would you suggest?
Cheers BournaVee
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Post by racket on Jun 24, 2017 6:02:50 GMT -5
Can't recommend a turbo , its more a case of trying to find something thats suitable , both with regards size as well as turbine wheel material/design , a 2-3,000 HP locomotive could have what you need .
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jun 24, 2017 7:08:28 GMT -5
Hi John, Thanks a lot. Still reading through the skuld thread, you really got me hooked to that engine..
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Post by racket on Jun 24, 2017 18:05:26 GMT -5
The TPE331 comp and turb parts come up on Ebay from time to time , or if you can find a friendly overhaul facility that might be persuaded to supply you with some bits from the "scrap bin"
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jun 25, 2017 0:58:38 GMT -5
i will be looking it up on Ebay. thank you so much. just that in Nigeria here its hard to find any aero bits.
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jul 6, 2017 17:59:44 GMT -5
hi please i would like to know if there are any problems associated with extracting shaft power from the main engine shaft. like the way solar t62 gas turbine does?
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CH3NO2
Senior Member
Joined: March 2017
Posts: 455
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Post by CH3NO2 on Jul 6, 2017 21:57:37 GMT -5
You need to have very well engineered gears to reduce the extreme RPM's of the shaft.
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jul 11, 2017 19:28:50 GMT -5
hi CH3no2, okay, what about the bearings? will the load not affect the engine bearings?
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CH3NO2
Senior Member
Joined: March 2017
Posts: 455
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Post by CH3NO2 on Jul 12, 2017 7:26:27 GMT -5
It certainly can. Directly gearing down a turbo shaft to do work is a specialty field of advanced engineering. It's done all the time on larger turbines, by aerospace and power generation companies, but I have never heard of it implemented by amateurs.
Another example is from a automotive company like Pro Charger. They do it in reverse however. They use a engine fan belt to drive a pulley which drives a gear box which is used to power up a super charger compressor wheel to 60,000+ RPM.
It's possible but not easy to do.
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Jul 12, 2017 18:13:57 GMT -5
alright, thank you
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Aug 18, 2017 3:48:45 GMT -5
Hello every one. I know its been a while. Thanks for all the advice and assistance you've given me.
I've finally started the turbine helicopter project. The frame has been constructed.
I'm going with my 91mm turbine system. I recently acquired the required ball bearings for the system. The combustion chamber is 110mm in height and 208.6 mm as outer diameter.
Can't seem to find a way to upload the pictures via mobile.
Cheers! BournaVee
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bournaVee
Junior Member
Joined: January 2017
Posts: 66
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Post by bournaVee on Aug 25, 2017 4:52:22 GMT -5
Hi My combustion chamber is 150mm in length and 8 inches in diameter. John, anders, jeff
1) what size of holes can I use for the primary, secondary and tertiary holes.
* I obtained NSK 6203DD7D duplex bearings. The outer ring of these bearings have two O-ring grooves machined into them.
So how do you suggest I used them? And does anyone know how to make O-rings. So sorry about the absense of pictures. I sold my computer to get funds for these. But if anyone needs pics just send me your email address
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Post by racket on Aug 26, 2017 0:56:31 GMT -5
Hi BournaVee
Without a lot more details about your flametube its impossible to recommend hole sizes etc etc .
Same with the bearings needing O rings , what are the groove dimensions ??
Cheers John
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