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[WIP] Nert's Dev Thread - Current: various updates


Nertea

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35 minutes ago, CDSlice said:

For someone who doesn't know a ton about the performance trade offs between methalox, hydrolox, and whatever liquid fuel is supposed to represent, @Nertea would you mind sharing what the intended role these methane engines will have? Like when would I want one of these instead of a fuel dense, but heavy liquid fuel engine or a more efficient, lighter weight, not fuel dense hydrogen engines?

So a basic view of fuels:

Kerolox or liquid fuel and oxidiser is the staple rocket fuel. Its great for first stages when you need a lot of punch but don't care too much about efficiency. In general it does it all in terms of getting to LEO. For example the Saturn IV first stage and Atlas V first stages burn kerolox.

Hydrolox or lqd hydrogen and oxidizer is the king of efficiency, being the lightest element it can be accelerated to high speed easily but do to the light weight it doesn't produce as much thrust. Hydrolox isn't used so much for first stages because it isn't that dense so it needs a lot of room to expand. Saturn IV second and third stages as well as the Space Shuttle burn this.

Methalox or lqd methane and oxidiser generally takes the best of both worlds. being relatively light it gives greater efficiency but being a hydrocarbon like kerosene it has a higher energy density so you don't need massive tanks to store it in. This can be used for both first and second stages but it is best used for first stages. Rockets like the Vulcan and Blue Origin's New Glenn(New Glenn technically uses liquid natural gas which is mostly methane but with a bit of ethane, for our purposes it is the same) will use methalox for their first stage and hydrolox for their second stages.

Hope this helps a bit

 

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4 hours ago, CDSlice said:

For someone who doesn't know a ton about the performance trade offs between metholox, hydrolox, and whatever liquid fuel is supposed to represent, @Nertea would you mind sharing what the intended role these methane engines will have? Like when would I want one of these instead of a fuel dense, but heavy liquid fuel engine or a more efficient, lighter weight, not fuel dense hydrogen engines?

You got a good overview in the other post, but overall, those are two extremes. It's often described as a compromise fuel - you get *some* of the benefits of LH2 and some of kero. A few more real life things

  • cryogenic LOX and LCH4 are similar in temperature so common bulkheads are friendlier
  • LCH4 is easier to ISRU on Mars
  • Cryogenic LCH4 needs about 1/10th the cryocooler power to stop boiloff

In the mod, that gets reflected as compromise

  • Slower boiloff and cheaper boiloff mitigation, but still boiloff
  • Intermediate density
  • Similar mass ratio to LF (LH2 is crappy)

 

But yeah. 

unknown.png

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@Nertea, is there any particular reason you're including the control wire mount on the Raptor, when you don't usually include them in your engine models?

Ebosmc7.png

Also, what's the naming scheme like for these engines? We have aquatic mammals for the kerolox engines and volcanos for the hydrolox ones, I can't think of a middle ground between the two. Maybe dinosaurs to fit in with the raptor, or just birds like the old methalox engines in NFLV?

Edited by coyotesfrontier
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32 minutes ago, Spaceman.Spiff said:

Look up “Raptor rocket engine”

Find some of the latest photos

How in the heck is he supposed to model the devil’s spaghetti of wires and tubes

Same thing with pretty much any rocket engine. Usually that stuff is omitted, which is what makes the mount for those wires' inclusion here notable. Personally, I think it's there because the engine would be kinda visually unbalanced otherwise.

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On 2/6/2021 at 11:54 AM, coyotesfrontier said:

@Nertea, is there any particular reason you're including the control wire mount on the Raptor, when you don't usually include them in your engine models?

Also, what's the naming scheme like for these engines? We have aquatic mammals for the kerolox engines and volcanos for the hydrolox ones, I can't think of a middle ground between the two. Maybe dinosaurs to fit in with the raptor, or just birds like the old methalox engines in NFLV?

It's not really the control wire mount, it's the main valve array. I have included only the startup line from there, the rest are not connected. The control box is on the other side and fairly small so not modeled. The answer though is that I model things needed to represent the look of the engine. The struts and the various greebles on them are fairly unique to the raptor, so they have been included.

unknown.png

I haven't decided on naming yet. Worth noting that this is a bit more subtle though:

  • NFLV lowers: sea mammals
  • NFLV uppers: cats
  • CE lowers: earth volcanoes
  • CE uppers: martian volcanoes

There will probably be one set for uppers and lowers then. Maybe dinosaurs and birds?

Other names of note, used by Squad, include bears (cub, kodiak), sails, dogs (only consistent one). 

Edited by Nertea
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7 minutes ago, Nertea said:

It's not really the control wire mount, it's the main valve array. I have included only the startup line from there, the rest are not connected. The control box is on the other side and fairly small so not modeled. The answer though is that I model things needed to represent the look of the engine. The struts and the various greebles on them are fairly unique to the raptor, so they have been included.

unknown.png

I haven't decided on naming yet. Worth noting that this is a bit more subtle though:

  • NFLV lowers: sea mammals
  • NFLV uppers: cats
  • CE lowers: earth volcanoes
  • CE uppers: martian volcanoes

There will probably be one set for uppers and lowers then. Maybe dinosaurs and birds?

Other names of note, used by Squad, include bears (cub, kodiak), sails, dogs (only consistent one). 

Holy hell, I'm in love! This is going to be a gorgeous engine I can't wait to bolt to my ships.

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16 minutes ago, Spaceman.Spiff said:

It looks excellent. The question is whether our not you can use Waterfall to make flames spew out the sides :)

You could do monkey themed engines. 

Chimp

Gorilla

Howler

Spider (wait)

tamarin

Saki

IDK

 

That would be fun for tiny engines

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Revised content list (names are not really final), with approximate completion levels. 

0.625m

  • [80%] Compsognathus: ESA Prometheus
  • [80%] Hawk: NASA RS-18

1.25m

  • [80%] Deinonychus: SpaceX Raptor
  • [80%] Buzzard: Avio M10

1.875m

  • [40%] Dromaeosaur: Blue Origin BE-4
  • [80%] Harrier: Landspace TQ11/12

2.5m

  • [95%] Allosaur: Methalox STBE concept (that I originally built for NFLV)
  • [80%] Kite: SpaceX Raptor Vacuum. 

3.75m

  • [60%] Tyrannosaur: 7x Raptor cluster in a cylindrical boattail
  • [30%] Vulture: BE-4U with extensible nozzle
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3 minutes ago, Nertea said:

Revised content list (names are not really final), with approximate completion levels. 

0.625m

  • [80%] Compsognathus: ESA Prometheus
  • [80%] Hawk: NASA RS-18

1.25m

  • [80%] Deinonychus: SpaceX Raptor
  • [80%] Buzzard: Avio M10

1.875m

  • [40%] Dromaeosaur: Blue Origin BE-4
  • [80%] Harrier: Landspace TQ11/12

2.5m

  • [95%] Allosaur: Methalox STBE concept (that I originally built for NFLV)
  • [80%] Kite: SpaceX Raptor Vacuum. 

3.75m

  • [60%] Tyrannosaur: 7x Raptor cluster in a cylindrical boattail
  • [30%] Vulture: BE-4U with extensible nozzle

Yay! Can't wait.

Edited by Fusion confusion
Bad grammar
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1 hour ago, Nertea said:

Revised content list (names are not really final), with approximate completion levels. 

0.625m

  • [80%] Compsognathus: ESA Prometheus
  • [80%] Hawk: NASA RS-18

1.25m

  • [80%] Deinonychus: SpaceX Raptor
  • [80%] Buzzard: Avio M10

1.875m

  • [40%] Dromaeosaur: Blue Origin BE-4
  • [80%] Harrier: Landspace TQ11/12

2.5m

  • [95%] Allosaur: Methalox STBE concept (that I originally built for NFLV)
  • [80%] Kite: SpaceX Raptor Vacuum. 

3.75m

  • [60%] Tyrannosaur: 7x Raptor cluster in a cylindrical boattail
  • [30%] Vulture: BE-4U with extensible nozzle

I vote a big one be named after Quetzalcoatlus. Sure, technically not a dinosaur, but pterosaur's close enough and it was the largest living thing known to ever fly.

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11 hours ago, Nertea said:

Revised content list (names are not really final), with approximate completion levels. 

0.625m

  • [80%] Compsognathus: ESA Prometheus
  • [80%] Hawk: NASA RS-18

1.25m

  • [80%] Deinonychus: SpaceX Raptor
  • [80%] Buzzard: Avio M10

1.875m

  • [40%] Dromaeosaur: Blue Origin BE-4
  • [80%] Harrier: Landspace TQ11/12

2.5m

  • [95%] Allosaur: Methalox STBE concept (that I originally built for NFLV)
  • [80%] Kite: SpaceX Raptor Vacuum. 

3.75m

  • [60%] Tyrannosaur: 7x Raptor cluster in a cylindrical boattail
  • [30%] Vulture: BE-4U with extensible nozzle

Instead of Dromaeosaur, Achillobator would fit better imo, since it is actually bigger than a Deinonychus (unlike the Dromaeosaurus), doesn't have the saurus suffix and is actually in the same subfamily of Dromaeosaur (Dromaeosauridae Dromaeosauridae).
Allosaur could also be replaced by Baryonyx or Suchomimus, if wanting to get rid of the suffix. The Tyrannosaur name should probably stay, as the beefiest methalox engine (cluster) deserves to be named after the heaviest and most famous theropod.

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1 minute ago, Erik3003 said:

Instead of Dromaeosaur, Achillobator would fit better imo, since it is actually bigger than a Deinonychus (unlike the Dromaeosaurus), doesn't have the saurus suffix and is actually in the same subfamily of Dromaeosaur (Dromaeosauridae Dromaeosauridae).
Allosaur could also be replaced by Baryonyx or Suchomimus, if wanting to get rid of the suffix. The Tyrannosaur name should probably stay, as the beefiest methalox engine (cluster) deserves to be named after the heaviest and most famous theropod.

I would like to keep the deinonychus, since it is one of my favourite dinosaurs (*cough from ARK cough*)

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Since we're talking names, I'd like to go ahead and share the idea of "Blue Falcon" for the vacuum BE-4. It is a reference to Blue Origin, while also keeping with the "birds of prey" theme. Plus has another hidden meaning that some might pick up on. 

As for the vacuum Raptor, how about the name "Raven"?

By the way, very nice work on the SL Raptor, it's crazy to see how much it has evolved from the old NFLV model. And really goes to show how much the real-world version has changed since Elon first teased the design back then!

Edited by lemon cup
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