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kbd512

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Registered: 2015-01-02

Posts: 7,577

SSTO Engine Technology

For SSTO to work, we do require very high performance LOX/LCH4 or LOX/RP1 engines, so to kick off this topic I present the following:

Launcher's E-2 LOX/RP1 Oxidizer-Rich LOX-Cooled Staged Combustion Engine

Rather than just watching a video of the engine, beautiful as that is, you get to see the performance data onscreen:
E-2 Test - Highest-performance kerosene rocket engine turbopump ever manufactured in the U.S.

My favorite video of the E-2 engine (brilliant blue flame, just like Methane and Hydrogen):
Who has ever seen a LOX/Kerosene liquid engine with a blue plume?

The characteristic sooty exhaust from most LOX/RP1 engines is replaced by a brilliant blue and orange flame, without a trace of soot, except for a very brief puff at startup and shutdown.

Thrust: 22,000lbf / 97,861N
O/F Ratio: 2.62:1
Isp: 365s (vac)
C* Efficiency: 98%+
Chamber Pressure: 100 bar

Turbopump Characteristics (you can see some of this data live during an engine test if you watch the first YouTube video link)
Pressure: 310 to 330 bar
Efficiency: 72%+
Power: 1.4MW
Pre-Burner Temperature 200°C
Inducer / Impeller rpm: 30,000
Impeller Material: 3D printed from Inconel 718
Combustion Chamber: 3D printed CuCrZr alloy using AMCM M 4K 3D metal printer
Co-Axial Injector: 3D printed using a Velo3D Sapphire 3D metal printer
Nozzle Diameter: 16 inches

Edit:
I forgot one other little tidbit about this engine- 99%+ combustion efficiency was ultimately achieved.  It's a fine-tuned hypersonic speed machine.  The exhaust plume makes it look just like a miniature Raptor.

Last edited by kbd512 (2024-05-25 20:52:53)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,224

Re: SSTO Engine Technology

With a heavy ship in the near approximate launch mass of a falcon Heavy 9 and this fuel type.

PROPELLANT    LOX / RP-1

ENGINES MERLIN SEA LEVEL

Merlin is a family of rocket engines developed by SpaceX for use on its Falcon 1, Falcon 9 and Falcon Heavy launch vehicles. Merlin engines use RP-1 and liquid oxygen as rocket propellants in a gas-generator power cycle. The Merlin engine was originally designed for recovery and reuse.

THRUST    845 kN / 190,000 lbf

ENGINES MERLIN VACUUM

Merlin Vacuum features a larger exhaust section and a significantly larger expansion nozzle to maximize the engine’s efficiency in the vacuum of space. Its combustion chamber is regeneratively cooled, while the expansion nozzle is radiatively cooled. At full power, the Merlin Vacuum engine operates with the greatest efficiency ever for an American-made hydrocarbon rocket engine.

THRUST    981 kN / 220,500 lbf

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,224

Re: SSTO Engine Technology

GW post on engines and equations

GW Johnson just posted a couple of studies on Single Stage to Orbit and Two Stage to Orbit ....

The spreadsheets can be provided if anyone is interested in seeing them.

Attached are copies in pdf format of two articles I wrote and just recently published on "exrocketman".   They are bounding calculations on what can be done toward expendable and reusable vehicles to reach Earth orbit from the surface.  One investigates and bounds what can be done SSTO.  The other investigates and bounds TSTO.  If you want to post these in the drop box thingie,  go ahead. 

<snip>

This is very simple rocket equation stuff,  done in a couple of spreadsheets.  The ascent-averaged Isp data come from other stuff I have recently published on "exrocketman",  about estimating rocket engine performance.  Some of that was done with a version of the bell nozzle rocket spreadsheet used in the orbits+ course.  The free-expansion stuff came from a post on "exrocketman" dealing with aerospike nozzles.  If anyone wants the spreadsheets,  they can have them.

GW

The first file is to be linked from here (SSTO):
https://www.dropbox.com/scl/fi/hu5zc3qc … 3lptv&dl=0

The second file is to be linked from here (TSTO):
https://www.dropbox.com/scl/fi/4dnyyqjn … gsvmd&dl=0

Here is an update:

This is the one that supports the other two you just posted for me.  I meant to post this on "exrocketman" some time ago,  but never got around to it until today. 

It shows vividly just how easy it is to use the "r noz alt" worksheet in the "liquid rockets.xls" spreadsheet file,  plus the Paintbrush-made "engine sizing report.png" file to very rapidly size multiple engines and run trade studies.  This is where I got my recommendations for how to size a fixed "compromise" bell nozzle to get really good ascent performance out of it. 

That spreadsheet file is an update of the one that is part of the orbits+ course materials.  I took that one,  deleted the extraneous worksheets,  added an altitude performance calculation block with automatic plots,  and added a output data block that works perfectly with a "Paintbrush"-made engine sizing report. It becomes cut-and-paste with some minor edits to report a design.

The multiple engine designs I sized for the trade study also make a good data library.  Pdf document file attached.  It should go with the other two,  which were "Bounding Calculations for SSTO Concepts" and "Bounding Calculations for TSTO" that you just posted for me.

Link to pdf goes here:
https://www.dropbox.com/scl/fi/s8v6c0zc … upmdo&dl=0

(th)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,224

Re: SSTO Engine Technology

I began to wonder if the Falcon first stage with modifications would be capable of a single stage to orbit.

https://en.wikipedia.org/wiki/Falcon_9_Full_Thrust

Mass (without propellant)[39]    22,200 kg (48,900 lb)
Mass (with propellant)    433,100 kg (954,800 lb)
Liquid oxygen tank capacity 287,400 kg (633,600 lb)
Kerosene tank capacity 123,500 kg (272,300 lb)
Payload fairing      1,700 kg (3,700 lb)

Thrust (stage total)[4]    7,607 kN (1,710,000 lbf) (sea level)
Specific impulse    Sea level: 282 seconds[