Author Topic: The Reaction Engines Skylon Master Thread (1)  (Read 746203 times)

Offline simonbp

  • Science Guy
  • Senior Member
  • *****
  • Posts: 7138
  • Liked: 314
  • Likes Given: 183
Re: Skylon
« Reply #160 on: 05/17/2011 08:27 pm »
Maybe something that the U-2 spy-plane used?
Two of the four wheels dropped after take-off.
Would allow you to have a quite heavy landing gear capable of emergency landings right after take-off, and you don't need to carry them all the way to orbit.

They sorta do that: in case of an abort during the runway roll, they have water-cooled brakes on the gear. After a successful liftoff, they dump the unneeded tonne-or-so of water overboard.

Offline tnphysics

  • Regular
  • Full Member
  • ****
  • Posts: 1072
  • Liked: 1
  • Likes Given: 0
Re: Skylon
« Reply #161 on: 05/19/2011 10:26 pm »

Makes sense! One other idea-what about another heat exchanger, from the hot He from the precooler directly to the GH2 from the first heat exchanger it passes through? Might cut the amount of LH2 needed significantly, at the expense of very high temperature hydrogen heat exchangers being needed (but doesn't the preburner already need that)?


I am not quite sure I understand this one.  The precooler (which is staged so is HX1 and HX2) is followed by HX3 in the preburner to further heat the Helium up so it has the power (100’s megawatts) to drive the turbines and pumps, we do not want to do any cooling of the Helium until it has done its work.  It is a classic thermodynamic cycle using the temperature difference between the heating end (HXs 1 to 3) and the cooling end HX 4 and we want to maximise the temperature difference.

This would be a separate heat exchanger that would operate in parallel (not series) to HX1 and HX2 and their associated turbomachinery. It would do no work, but it would cool air, allowing lower H2 flows-and thus greater airbreathing Isp.

My understanding of it is that there is an abundance of power at these high airspeeds.

I was thinking that the amount of LH2 needed could be cut in half!

Offline bolun

  • Senior Member
  • *****
  • Posts: 3557
  • Europe
  • Liked: 970
  • Likes Given: 110
Re: Skylon
« Reply #162 on: 05/24/2011 07:33 am »
UK Skylon spaceplane passes key review

24 May 2011

http://www.bbc.co.uk/news/science-environment-13506289

Offline Hempsell

  • Full Member
  • *
  • Posts: 145
  • Liked: 63
  • Likes Given: 0
Re: Skylon
« Reply #163 on: 05/24/2011 08:57 am »
You may also like to look at

http://www.bis.gov.uk/ukspaceagency

Where you can download the UK Space Agency’s report

Offline bolun

  • Senior Member
  • *****
  • Posts: 3557
  • Europe
  • Liked: 970
  • Likes Given: 110
Re: Skylon
« Reply #164 on: 05/24/2011 12:55 pm »

Offline simonbp

  • Science Guy
  • Senior Member
  • *****
  • Posts: 7138
  • Liked: 314
  • Likes Given: 183
Re: Skylon
« Reply #165 on: 05/24/2011 07:34 pm »
Very nice; lots of great info!

One thing that stuck out to me:

Quote
The pre-burner is required to handle a large range of flow rates and mixture ratio variations in the course of the SKYLON mission. This said; its function differs from that of a classical pre-burner in that, whereas a classical staged combustion approach uses the output of the pre-burner to directly power the turbomachinery for the pumps, the SABRE engine uses it as a heat source to top off the heat input into the helium loop. The helium then goes on to power the turbo-machinery for the turbo-compressor and LOX pumps.


So, in process of designing SABRE, they've managed to reinvent the staged-combustion rocket. Would there be any advantages to doing this for a conventional staged-combustion rocket?
« Last Edit: 05/24/2011 07:34 pm by simonbp »

Offline vt_hokie

  • Senior Member
  • *****
  • Posts: 3054
  • Hazlet, NJ
  • Liked: 118
  • Likes Given: 436
Re: Skylon
« Reply #166 on: 06/01/2011 11:51 pm »
I can't help but think that this is the type of thing NASA would be doing today, were this country still bold enough to take on difficult challenges and do great things...

http://www.zdnet.co.uk/news/emerging-tech/2011/05/27/esa-gives-green-light-to-skylon-spaceplane-40092913/


Offline QuantumG

  • Senior Member
  • *****
  • Posts: 9238
  • Australia
  • Liked: 4477
  • Likes Given: 1108
Re: Skylon
« Reply #167 on: 06/01/2011 11:54 pm »
The US doesn't have a supply of the unique fuel required to develop Skylon.. I hear North Korea might be helping out.

Yes Brobof, I stole your joke.
« Last Edit: 06/01/2011 11:55 pm by QuantumG »
Human spaceflight is basically just LARPing now.

Offline docmordrid

  • Senior Member
  • *****
  • Posts: 6334
  • Michigan
  • Liked: 4207
  • Likes Given: 2
DM

Offline vt_hokie

  • Senior Member
  • *****
  • Posts: 3054
  • Hazlet, NJ
  • Liked: 118
  • Likes Given: 436
Re: Skylon
« Reply #169 on: 06/01/2011 11:59 pm »

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
Re: Skylon
« Reply #170 on: 06/02/2011 12:08 am »
Skylon is another middle massed payload to LEO launch vehicle which will therefore have several rivals.  What we need is something that can go beyond Earth orbit (BEO).

Could the Skylon be refuelled at an orbital base station and fly to Earth-Moon Lagrange 1 or low lunar orbit?  (Delta-V of 3.77 km/s and 4.04 km/s respectively.)

Depending on its heat shield design the Skylon could either perform a direct re-entry or make a powered fly back to LEO.

Offline docmordrid

  • Senior Member
  • *****
  • Posts: 6334
  • Michigan
  • Liked: 4207
  • Likes Given: 2
Re: Skylon
« Reply #171 on: 06/02/2011 12:53 am »
Once in orbit it's just another hydrolox engine cluster, but with all the added mass of the spaceplane form factor.

Probably better to let it do its designed job, medium payload or crew to LEO, and let something else much simpler & lighter be the EDS/mission engine.
DM

Offline ciscosdad

  • Full Member
  • *
  • Posts: 169
  • Liked: 16
  • Likes Given: 179
Re: Skylon
« Reply #172 on: 06/02/2011 04:00 am »
What is the music in the first segment of that video?
Dvorzak? Stirring stuff!

Edited on 13th June: The music is Karelian Suite Intermezzo by Sibelius.  Probably conducted by Paavo Berglund with the London Symphony Orchestra. (Thanks to Reaction Engines Public Affairs Officer).
« Last Edit: 06/13/2011 12:25 am by ciscosdad »

Offline rjholling

  • Full Member
  • **
  • Posts: 224
  • Liked: 0
  • Likes Given: 0
Re: Skylon
« Reply #173 on: 06/02/2011 04:14 am »
What is the music in the first segment of that video?
Dvorzak? Stirring stuff!
Kind of off topic but this is the same music they play at the beginning of 'Triumph of the Will'. (I only know this because I had to watch it for a class freshman year)

Back on topic.  I always wished that we would have continued with the X-33 and VentureStar.  The issue with the propellant tanks could have been solved by using Li-Al alloy tanks.  The metallic heat shield would have solved a lot of the issues with the orbiters with regards to cost/safety.  Hopefully the people on the other side of the pond will actually build this and make it work.

Offline Downix

  • Senior Member
  • *****
  • Posts: 7082
  • Liked: 22
  • Likes Given: 1
Re: Skylon
« Reply #174 on: 06/02/2011 04:34 am »
What is the music in the first segment of that video?
Dvorzak? Stirring stuff!
Kind of off topic but this is the same music they play at the beginning of 'Triumph of the Will'. (I only know this because I had to watch it for a class freshman year)

Back on topic.  I always wished that we would have continued with the X-33 and VentureStar.  The issue with the propellant tanks could have been solved by using Li-Al alloy tanks.  The metallic heat shield would have solved a lot of the issues with the orbiters with regards to cost/safety.  Hopefully the people on the other side of the pond will actually build this and make it work.
In both cases, Al-Li tanks on X-33/VS and metalic heatshield on shuttle, they would have lost performance due to weight.  The VentureStar would no longer be able to reach orbit, and the Shuttle could no longer deliver the payloads it does.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline nacnud

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2691
  • Liked: 981
  • Likes Given: 347
Re: Skylon
« Reply #175 on: 06/02/2011 06:11 am »
Could the Skylon be refuelled at an orbital base station and fly to Earth-Moon Lagrange 1 or low lunar orbit?  (Delta-V of 3.77 km/s and 4.04 km/s respectively.)

Reaction Engines suggest the use of a reuseable upper stage for this role, no need to send skylon beyond LEO.

http://www.reactionengines.co.uk/fluyt.html

Offline Crispy

  • Member
  • Full Member
  • ****
  • Posts: 1025
  • London
  • Liked: 783
  • Likes Given: 51
Re: Skylon
« Reply #176 on: 06/02/2011 09:36 am »
So, in process of designing SABRE, they've managed to reinvent the staged-combustion rocket. Would there be any advantages to doing this for a conventional staged-combustion rocket?

Not that I can see. A regular engine doesn't need the helium loop for cooling incoming supersonic airflow. It would only add inefficiency to the standard staged combustion process.

Anyway, this is excellent news for Skylon. Hope the testing is going well!

Offline Seer

  • Member
  • Full Member
  • **
  • Posts: 251
  • Liked: 6
  • Likes Given: 1
Re: Skylon
« Reply #177 on: 06/03/2011 08:44 pm »
I noticed that the sabre engine uses high pressure staged turbopump driven rocket engines that are similar to the ssme. Given the maintance costs of those engines, this might be a problem.

Offline aero

  • Senior Member
  • *****
  • Posts: 3629
  • 92129
  • Liked: 1145
  • Likes Given: 360
Re: Skylon
« Reply #178 on: 06/03/2011 10:37 pm »
I noticed that the sabre engine uses high pressure staged turbopump driven rocket engines that are similar to the ssme. Given the maintance costs of those engines, this might be a problem.
Maybe - but we need to remember that the Shuttle/SSME has always been man-rated while the Skylon/Sabre is not, at least initially. That difference should relax the engine reliability requirements somewhat. Then there is the 40 years of advancement in material science from the SSME to the Sabre that may also be applied to improve reliability.
« Last Edit: 06/03/2011 10:41 pm by aero »
Retired, working interesting problems

Offline Seer

  • Member
  • Full Member
  • **
  • Posts: 251
  • Liked: 6
  • Likes Given: 1
Re: Skylon
« Reply #179 on: 06/03/2011 11:17 pm »
one further question:when in rocket mode, why not use the airflow coming into the sabre engine as reaction mass? I.e, air augmented thrust.

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1