What's the best 30,000 lb+ class gas turbine engine?

[SgtPappy]

Hello,

 

I'm working on a group project for one of my final year courses, in which the requirements are to design a 150-passenger, 12,500 km range, Mach 2.1+ supercruising airliner (doesn't have to supercruise at Mach 2.1).

 

Does anyone have ideas as to what engine I could use that produces over 30,000 lbf of static, wet, sea level, uninstalled thrust? I can't find thrust curves for the newer engines like the F110-GE-132.

 

Info on my ideas

 

I'm trying to find information on low frontal area, low-bypass turbofan engines that can produce 30,000 lbf of static, wet, sea level, uninstalled thrust. The closest I got was the F110-GE-129 and the F100-PW-229. I have thrust and specific fuel consumption for both when installed in an F-16C. Preferably, I would like to utilize the F110-GE-132 as it has massive thrust, but I cannot find performance curves anywhere. I like these smaller engines because they are not much larger in diameter than the Concorde's engine, yet they produce almost as much thrust.

 

Unfortunately, I cannot upload the design here as my group captain has not allowed me, but from preliminary calculations, we assume we need almost as much thrust as the Concorde. We have yet to aerodynamically simulate the aircraft in Fluent.

 

Thanks for your help!

[Exorcet]

The Concorde was a supercruiser with specially made low bypass turbofans. The exhuast velocity on dry thrust was probably higher than what you'll get on those fighter engines so even though they'll produce more thrust at SL while stationary, they could lose out at altitude and high Mach number.

 

Not to say you couldn't supercruise, but you'll either lose out on range or speed without purpose built engines. And this is off the top of my head as I'm not too familiar with the specifics of these engines, so if you find figures that say otherwise, go with them.

 

Is there any info on the EJ200's? The EF-2000 seems to supercruise fine and I think there were plans for thrust growth at some point.

 

Good luck, I had a project like this. Finding info on anything was pain!

[SgtPappy]

Oh man tell me about it!

 

Thanks for the quick input. I thought about the EF-2000's engines but they're a tad too weak for the size of plane we're doing. I'll definitely look into it. Though as I see it now, we'd need 5 or 6 Eurofighter engines. What engine did you use when you designed your plane?

 

It will be about 300 ft long with variable geometry wings. With the wings swept forward and at subsonic speed, canards are needed for stability and a larger moment arm.

[Exorcet]

I don't think our engines would cut it, they were props.

 

We needed to do an ultra long endurance high altitude recon UAV to replace the U-2 and GlobalHawk.

[marcos]

Oh man tell me about it!

 

Thanks for the quick input. I thought about the EF-2000's engines but they're a tad too weak for the size of plane we're doing.

Use more of them. The XB-70 had 6 engines.

 

The Rolls-Royce Olympus 593 is about the only engine capable of Mach 2+ supercruise.

 

http://en.wikipedia.org/wiki/Rolls-Royce/Snecma_Olympus_593

 

And my $0.02. If a cost effective supersonic airliner could be built, it already would have been.

 

I like these smaller engines because they are not much larger in diameter than the Concorde's engine, yet they produce almost as much thrust.

That's the perfect argument for using the Olympus 593.

 

This has some info. on specific fuel consumption for F110-X:

 

http://maecourses.ucsd.edu/~adrake/mae155b-sp09/marauder/marauder_1.pdf

Edited February 4, 2013 by marcos

[Exorcet]

That's the perfect argument for using the Olympus 593.

They're out of production though, which is probably why they're not being considered.

 

And a bit off to the side, but on the subject of affordable supersonic airliner, it seems some progress has been made on the Busemann Biplane configuration, but I've not followed up on it.

Edited February 4, 2013 by Exorcet

[marcos]

Well the Busemann Biplanes that I've seen don't look to have accommodation for 150 passengers.

 

The only other in-production engine I can think of for supercruise is the F119.

 

But wrt Mach 2 supercruise. I honestly believe the Olympus 593 and the GE Y93-GE-3 from the XB-70 are the only engines that would have a chance.

 

Mach 2 supercruise is a radically design requirement than that of any engine currently in production, so you'd just be hammering square pegs into round holes. Even the likes of the Typhoon, Rafale and F-22 engines aren't designed to peak in performance as late as Mach 2. In fact most fighter engines are designed to peak in the transonic region.

 

[SgtPappy]

Technically it's not a requirement to supercruise at mach 2, although if possible, that'd be fantastic.

 

I think we're aiming to supercruise at around 1.6-1.8.

 

I'll present the case of up to 6 EJ200's, but my group has discounted using turbojets due to the lack of fuel efficiency at low supersonic speed.

 

THanks for the data and presentation, Marcos. Did you manage to find thrust and specific fuel consumption for this F100-PW-232?

Edited February 4, 2013 by SgtPappy

[RIPTIDE]

What about the NK-32? I think they are ~30,000 Dry?

[marcos]

Technically it's not a requirement to supercruise at mach 2, although if possible, that'd be fantastic.

 

I think we're aiming to supercruise at around 1.6-1.8.

 

I'll present the case of up to 6 EJ200's, but my group has discounted using turbojets due to the lack of fuel efficiency at low supersonic speed.

 

THanks for the data and presentation, Marcos. Did you manage to find thrust and specific fuel consumption for this F100-PW-232?

The difference between turbojet and turbofan is more semantics these days. Technically an EJ200 isn't a pure turbojet because it has a bypass stream (BPR 0.4:1 vs 0.36:1 for F-15's F100-X). The NK-32 has a BPR of 1.4:1 but a higher SFC than an Olympus 593 (BPR 0:1).

 

So don't get too hung up on the difference. Besides, the more air you bypass, the less likely you are to achieve a good supercruise speed.

 

The SFC for the F100-PW-232 is on page 10. Does nobody read links anymore?:D

http://maecourses.ucsd.edu/~adrake/mae155b-sp09/marauder/marauder_1.pdf

 

It was 0.76. Near as damnit same as EJ200. EJ200 is 10-15% better (less) on reheat 1.91 vs 1.65lb/lbf.hr). Relevant to transonic dash.

 

SFC

EJ200s SFC is 0.74-0.8lb/lbf.hr based on 21-23g/kNs dry vs 0.76 for F100-PW-232

 

EJ200 SFC is 1.65-1.72lbf/lb.hr on reheat vs 1.91 for F100-PW-232

 

Diameter - think drag

EJ200 - 0.737m

F100-PW-232 - 0.90mm (1.181m max. external)

 

Length

EJ200 - 4m

F100 - 4.8m

 

The F100 has the benefit of variable BPR - 0.34-1:1 but the cruise condition is at a constant high supersonic speed and acceleration will mostly be on reheat, so maybe not that useful for an airliner.

 

Weight

EJ200 - 2180lbs

F100 - 3740lbs

 

So you can have 3 EJ200s for 2 F100s. Area 5.11m^2 total vs 4.91m^2. That is based on internal diameter. The variable bypass F100 will have a relatively larger outer diameter.

 

Thrust-to-Weight

EJ200 - 9.175:1

F100 - 7.8:1

 

Thrust - 5 EJ200s ~ 4 F100s.

 

Other considerations.

1)EJ200 has an existing intake design for Mach 2 flight. F100 has the same for other versions but not the 232.

2) EJ230.:D

Edited February 4, 2013 by marcos

[SgtPappy]

Lol, of course we read links :P

 

I read your pdf and it's fantastic. I found the specs you posted but what I meant was that we needed curves. As you know, no parameter of an engine is constant at all altitudes and speeds (except maybe size, but even that is a little more obscure for high heat engines, right?) so I was thinking along the lines of graphs.

 

I apologize for forgetting to mention graphs.

 

Thanks for your posts and all this data! We're now looking towards the EJ230 you mentioned, and a buddy of mine is looking for the NK-32, though data for that seems equally hard to come by. Lastly, we're looking into the CTOL F-35A's F135-PW-100 engines. That thing seems like a beast.

[Exorcet]

Off the top of my head, the F135 is fat, long and probably isn't as optimized as the EJ200 for high speed. The F-35 is going to be doing a lot of long range cruising at subsonic speed, supercruise didn't seem to be a design goal. The EF is all about raw performance. I don't recall if it was meant to supercruise initially, but supersonic performance was a big goal and I'm not sure if the F-35 will ever see Mach 1.5 in level flight with dry thrust.

 

If you have the time it wouldn't hut to look, but the EJ200 is probably a better bet.

 

EDIT

 

Actually stepping back for a second, do you need justification on your ability to acquire the engine? The only reason I've not suggested the F119 is lack of info and that I doubt anything outside of the F-22 will use one for a couple of decades. I don't know how tightly wrapped the EJ200 is, but have you looked into its availability outside of military use?

 

If there are no restrictions on acquisition, and you can find figures, consider the F119. I don't think it will be easy, but then I don't know how easy it will be to get solid info on the EJ200 either.

Edited February 5, 2013 by Exorcet

[Sierra99]

Hello,

 

I'm working on a group project for one of my final year courses, in which the requirements are to design a 150-passenger, 12,500 km range, Mach 2.1+ supercruising airliner (doesn't have to supercruise at Mach 2.1).

 

Does anyone have ideas as to what engine I could use that produces over 30,000 lbf of static, wet, sea level, uninstalled thrust? I can't find thrust curves for the newer engines like the F110-GE-132.

 

Info on my ideas

 

I'm trying to find information on low frontal area, low-bypass turbofan engines that can produce 30,000 lbf of static, wet, sea level, uninstalled thrust. The closest I got was the F110-GE-129 and the F100-PW-229. I have thrust and specific fuel consumption for both when installed in an F-16C. Preferably, I would like to utilize the F110-GE-132 as it has massive thrust, but I cannot find performance curves anywhere. I like these smaller engines because they are not much larger in diameter than the Concorde's engine, yet they produce almost as much thrust.

 

Unfortunately, I cannot upload the design here as my group captain has not allowed me, but from preliminary calculations, we assume we need almost as much thrust as the Concorde. We have yet to aerodynamically simulate the aircraft in Fluent.

 

Thanks for your help!

 

http://en.wikipedia.org/wiki/Pratt_%26_Whitney_J58

 

You didn't specify if the engine hand to be presently available...

[marcos]

Lol, of course we read links :P

 

I read your pdf and it's fantastic. I found the specs you posted but what I meant was that we needed curves. As you know, no parameter of an engine is constant at all altitudes and speeds (except maybe size, but even that is a little more obscure for high heat engines, right?) so I was thinking along the lines of graphs.

Good luck finding them.:D I was working on the assumption of max dry thrust for supercruise and assuming the figures would be at a cruise-like altitude. Other than that I can't find any more information.

Edited February 5, 2013 by marcos

[SgtPappy]

Marcos, I will keep trying! I've got 2 more months of sleepless nights :P

 

Sierra, Technically, the engine we choose doesn't have to be production (i.e. our project requirements never say so) but we will be evaluated by people from Goodrich (UTC), Bombardier, Pratt & Whitney etc. and if we do not use an existent engine, they will grill us for sure.

 

Some information on the F135-100 out there state that the engine is capable of supercruise but it wasn't actually designed to do so. It's a very tempting choice because it's got 28,000 lb dry!

 

It seems that we may have to use 6x EJ200's though. At any rate, first thing's first, I'll get the propulsion guy in our group to find performance graphs concerning TSFC/SFC and thrust vs. altitude.

[marcos]

Marcos, I will keep trying! I've got 2 more months of sleepless nights :P

 

Sierra, Technically, the engine we choose doesn't have to be production (i.e. our project requirements never say so) but we will be evaluated by people from Goodrich (UTC), Bombardier, Pratt & Whitney etc. and if we do not use an existent engine, they will grill us for sure.

 

Some information on the F135-100 out there state that the engine is capable of supercruise but it wasn't actually designed to do so. It's a very tempting choice because it's got 28,000 lb dry!

In the F-35 the F135 will manage about Mach 1.2 according to available figures but that isn't a very good speed to cruise at because it's in the transonic region, and it's a higher BPR engine, so it's not as good for generating the fast exhaust jet that you need for supercruise.

 

It seems that we may have to use 6x EJ200's though. At any rate, first thing's first, I'll get the propulsion guy in our group to find performance graphs concerning TSFC/SFC and thrust vs. altitude.

Always best to delegate a task you can't do yourself.:P

Edited February 5, 2013 by marcos

[SgtPappy]

Looks like we'll be using 6x EJ200's if we can find a little more info on dry thrust at higher altitudes.

 

The F119 would have been ideal but there's next to nothing out there in terms of info, probably because the US was never interested in selling them to other countries.

[JozMk.II]

The Concorde was a supercruiser with specially made low bypass turbofans.

 

 

They're actually turbojets, not turbofans.

 

I'll present the case of up to 6 EJ200's, but my group has discounted using turbojets due to the lack of fuel efficiency at low supersonic speed.

 

The EJ200 is a turbofan, not a turbojet.

[marcos]

Looks like we'll be using 6x EJ200's if we can find a little more info on dry thrust at higher altitudes.

 

The F119 would have been ideal but there's next to nothing out there in terms of info, probably because the US was never interested in selling them to other countries.

Can't really help you there but if you're looking for a rule of thumb it's about 2/3rds that on reheat. So you could realistically look at getting about 66,000lbf from all 6 engines dry at 20,000ft and Mach 2.0.

 

I'm going to guess that's not enough unless you design it to have a very good L/D. The Concorde probably had about 50% more than that and only carried 120 passengers. I think we've probably been underestimating the amount of thrust this feat will take. You might get around Mach 1.6 with that though, which would still be twice as fast as regular airliners and probably deliver more passenger miles/gallon than a Concorde.

 

A slightly lower cruise speed would also reduce other design complexities. The Concorde's Mach 2+ wing design gave poor L/D as low speeds and the high alphas made landing complicated (the dipping nose). A design focused on Mach 1.6 would probably lessen those problems. You've also got things like skin friction and thermal cycling to consider, plus bird strike testing.

Edited February 6, 2013 by marcos

[Exorcet]

Looks like we'll be using 6x EJ200's if we can find a little more info on dry thrust at higher altitudes.

 

The F119 would have been ideal but there's next to nothing out there in terms of info, probably because the US was never interested in selling them to other countries.

 

OK. I was wondering is the EJ200 was also as protected, but if not your gain.

 

They're actually turbojets, not turbofans.

I suppose I'm still technically right, the bypass is so low it's zero. lol

 

Good catch though.

[SgtPappy]

The EJ200 is a turbofan, not a turbojet.

 

I was referring to the possibility of using Olympus engines.

 

marcos, unfortunately, the profs wanted something that was faster than the Concorde. It's nuts but that's what they want. Perhaps we can cruise at Mach 1.6, but maximum speed must be greater than the Concorde's ~2.05.

 

Also, our plane has variable sweep and has a 30 foot quiet spike. With the wings swept back, we've got around 70 degrees of sweep and an aircraft length of about 317 ft.

[Exorcet]

How much weight are the swing wings costing you? Are they full span?

 

Maybe you could use fixed wings and go with smaller retractable canards, or something similar for extra lift at low speed. It might end up being lighter, which would cut drag at cruise. Hard to say if this is a good idea without seeing the whole plane though, so you'll have to work it out with your team.

 

Also, have you looked into wave riding?

 

Oh and if feasible consider new vector thrust nozzles for the engines to assist with trim drag.

Edited February 7, 2013 by Exorcet

[marcos]

I was referring to the possibility of using Olympus engines.

 

marcos, unfortunately, the profs wanted something that was faster than the Concorde. It's nuts but that's what they want. Perhaps we can cruise at Mach 1.6, but maximum speed must be greater than the Concorde's ~2.05.

 

Also, our plane has variable sweep and has a 30 foot quiet spike. With the wings swept back, we've got around 70 degrees of sweep and an aircraft length of about 317 ft.

 

Well you could use 10 EJ200s then I guess or design a modern version of the Olympus 593 and use 4 of them. The only way to achieve it with 4 current engines is probably the NK-32s or the Kolesov RD-36-51s from the Tu-144.

 

I still think that the EJ200s would give better performance but using so many might be impractical.

 

Interestingly, the thrust at cruise might not be as great as I thought:

 

http://en.wikipedia.org/wiki/Tupolev_Tu-144

http://en.wikipedia.org/wiki/Kolesov_RD-36-51

 

5400kgf < 12000lbf each

 

So maybe 6 EJ200s would work. Highly theoretical here though. You really need to model your aircraft and find out how much drag you have at Mach 2.1.

[SgtPappy]

Exorcet, no the wings are not full span. The plane istelf has an almost flying wing look to it.. sorta like the one shown here: http://www.boeing.com/Features/2010/06/corp_envision_06_14_10.html

 

In terms of our wings, look at the Boeing SST in the link above and the swivelling portion is where the sweep abruptly decreases.

 

The group has decided to use 6x EJ200's and are considering the last-ditch possibility of extrapolating performance curves from the Olympus 593 into a fictional "modern Olympus".

[SgtPappy]

Ok, so I found another engine. The JTF-17A Turbofan which produces some 38,500 lbf dry thrust! Not quite sure if it's supercruising or not but it was a candidate for the B2707: www.dtic.mil/dtic/tr/fulltext/u2/804527.pdf

 

The Mk. 621 version of the Olympus 593 seems promising too but all these engines were never produced.