GOX liquid motor

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zburnt

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Over the past few days I have been getting started with general planning for a liquid rocket engine. I made a previous post about this and I received a lot of good input. That said, I have seen a lot of people confused about that post because my initial goals were completely different then the goals I came to at the end. So, this post is about a more specific plan.

The current plan is an engine fueled with either kerosene or methyl alcohol. The oxidizer will be gaseous O2. I will use compressed N2 to pressurize the liquid. This engine will only be static fired, and it will never fly. I will hopefully make a flyable engine much later, but that isn't the point of this post. I am doing some basic calculations with methyl alcohol as fuel from this site. After I have done this I will move on to plan from Sutton. Once I have a reasonable design I will look into CAD and simulations. My general design, at least to start, is following the design on the site. If you have any insight I would greatly appreciate it and if you have any questions I will do my best to answer. Thanks.
 
I would still start with a commercial hybrid, then EX hybrid then go on to your motor. You will learn lots on the way. (see reply on previous post)

Be safe...
 
I have no idea of what you already know and understand about liquid rocket engines. Hopefully there is nothing new in these, but for the vast majority of the TRF member that only deal with solid rocket motors, watching these three videos in order could give you a much better understanding of what liquid rocket engines are all about.

By Everyday Astronaut
1. Why don't rocket engines melt? How engineers keep engines cool.
2. Rocket engine cycles: How do you power a rocket engine?
3. How To Start A Rocket Engine // Chilldown, Spin Up, Thermal Conditioning & Ignition!
 
again, I advise you to find something else to do.

you do not have the skills to make that work. you do not know what knowledge you are missing.

come back when you have read Heister's "Rocket Propulsion" textbook, and have completed the exercises.

show your work.

seriously.
 
Something you may find interesting . . .

http://www.cientificosaficionados.com/libros/cohetes.pdf

Dave F.
Not sure if you read the link from Dave F in the previous thread. If you're doing GOX Methanol, I would suggest you use this as your fundamental guide.
Again, as someone who has worked on GOX Methanol engines: they are very safe, they aren't terribly difficult (as a static testing config) and they are an excellent starting point for liquids.

TP
 
again, I advise you to find something else to do.

you do not have the skills to make that work. you do not know what knowledge you are missing.

come back when you have read Heister's "Rocket Propulsion" textbook, and have completed the exercises.

show your work.

seriously.
Please let me know what knowledge I am missing, that would point me in a great place to continue on the process of learning. Also, (I’ve looked at Sutton somewhat, but not the book you mentioned), is Heisters better. (I will do my own research on this as well, just would like your opinion. Thanks!
Not sure if you read the link from Dave F in the previous thread. If you're doing GOX Methanol, I would suggest you use this as your fundamental guide.
Again, as someone who has worked on GOX Methanol engines: they are very safe, they aren't terribly difficult (as a static testing config) and they are an excellent starting point for liquids.

TP
Thanks for the link
 
As you are not using hypergolic fuels, you will need a source of ignition. This is where I see a lot of these types of engines fail. They don't get the atomization mixture right, so the engine runs fuel rich and mostly spits out black smoke, or combustion happens and chamber pressure blows out the ignition source (and I mean spark plug flying across a field like a bullet). I assume there has to be a way to model any design on a computer before you get around to blowing your fingers off.
 
As you are not using hypergolic fuels, you will need a source of ignition. This is where I see a lot of these types of engines fail. They don't get the atomization mixture right, so the engine runs fuel rich and mostly spits out black smoke, or combustion happens and chamber pressure blows out the ignition source (and I mean spark plug flying across a field like a bullet). I assume there has to be a way to model any design on a computer before you get around to blowing your fingers off.
Remember he's starting with *GOX* and fuel. GOX is probably the easiest thing to ignite with a fuel and you can't get dangerous hard starts with it. That's why it's such a perfect starting combination for liquid propulsion. Very safe and very easy to start. I've seen sparklers (yes the ones from the grocery store) *reliably* ignite GOX engines. The Hypertek ignition system used GOX and plain old speaker wire with HV arc to provide ignition to hybrids - no pyrotechnics necessary. GOX-acrylic hybrids have been used (fired) often for *indoor* demonstrators.

TP
 
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