automcdonough

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Posts posted by automcdonough


  1. I'm not sure if I have missed a key element of your design but it looks to me like the setup that you have is very very similar to what a generator/reactor/thermal jet combination already represents. You have intakes to take in the atmosphere, that gets fed into the reactor and heated to very high temperatures before being expelled out of the back to produce thrust. Optionally, you have a generator as well, which is where your suggestion differs slightly: currently the generator will have to do make do with leftover power after the engines have had what they want while you suggest losing thrust to keep the generator powered.

    That's the gist of it. Differs mainly just in physical package.


  2. well yeah. this would be a situation where there's nuclear energy source or something.

    Electrolysis works on electricity and is reasonably efficient at what it does. It doesn't have to heat the water into steam and cook it out, it just turns straight from liquid to gas. Using an arc isn't a great heat source. High temps but not a lot of heat (not really feeling your arc jet engine idea for that reason). Combusting that gas is where the vast majority of the heat comes from..


  3. So basically take a thermal jet, add a reactor, but limit both to only operating with atmospheric gases as a medium to save weight? Nice concept and does have a place in the game I think. See what Fractal thinks. (EDIT: Maybe vary output of both jet AND reactor to atmospheric pressure?)

    yes, sounds like you got what I'm thinking. :)

    The "one rotating part" would be the hypersonic ram that compresses that air before it enters the combustion chamber...

    Something we're all probably forgetting... Making the air pass through a nuclear reactor would make it rather highly radioactive...

    Well, I don't anticipate starting issues because a generator is also a motor. Just feed some juice in to spin things up until the compression and reactor heat take over. This should have no issues in VTOL application.. and actually because of the air offset it might be more efficient at normal speeds rather than hypersonic..

    Also, heat exchanger. No reason to expose radiation directly to atmosphere, don't want those soft metals sandblasted out the exhaust. Even if it's just a hard metal case that's good enough.

    On a related note, the type of craft this is targeted for won't have a whole lot of electric demand. It would be overkill solid for typical science transmission and rover wheels. So maybe a few purely electric powered fans are in order? Electrolysis refuel? Jet with electric plasma arc as the combustion? maybe feed some fuel in as afterburner/boost. who knows. Just brainstorms. Do what you will. :) I know the intakes for this mod suck down some power and those would kinda be built-in to this. Unless of course they are just generators for a science base or something, but likely the larger reactors would be chosen for that.


  4. So I have a little concept for you guys. Some inspiration, food for thought. Not that you seemed bored and in need of new part ideas but here it is anyway.

    To start, put the thermal jet engine in your brain. Runs off nuke as the heat source for the typical "combustion" stage. right?

    now:

    BGRPksU.jpg

    This is a combined jet engine and generator. The performance is basically that of a jet, but if the generator loads it down then thrust will drop. On the other hand, it can generate a fair amount of juice this way. It only functions if there's atmosphere, but does not require any fuel other than the reactor. As a generator, it should be lightweight and efficient compared to the one's we're used to in this mod (But it only works in atmosphere).

    t32KgvU.jpg

    This is a side-mount concept featuring two of those offset jet generator things into an integrated reactor. Basically a one-stop shop to make something move in the atmosphere. It's by itself here so no scale, but I imagine a small one would have a probe with small wings cruising nicely or make a rockin KAS jetpack. Or just a really convenient generator. Normal size would be similar thrust to a single turbojet and capable of jamming out a few MJ if needed. Maybe half actually.. Very modest, but also very lightweight. Ideal for a scout type plane setup where you aren't looking to charge an FTL jump or anything.

    yMl6bR1.jpg?1

    similar concept, this is a larger inline style shown with Mk 1 cockpit and sandwiched between 2 fuel tanks. Not that it needs fuel but this layout kinda makes a hole for something to go there. The scale I drew is also kinda big, that thing would haul ass. Probly oversized.

    This could perhaps be a large sidemount meant to stick onto existing reactor part. Again, mostly redundant to the existing thermal jet but contains generator. as a non-integrated setup it seems maybe too redundant? Nice to have side-mount option at least.


  5. You end up with hot water in the exhaust. Splitting water into HHO and then burning it is just an especially complex way to go from cold water to hot water, and you can get the same result by using electricity to heat the water in a simpler way, for example magnetic induction (like a microwave oven).

    Arcs generate very high temperatures, and are a decent way to heat water. Some energy will be lost electrolyzing water, but as you pointed out, the products will combust almost immediately, giving that energy back, so you don't get more energy than any other heating method, but you get very high temperatures (high ISP) for a rather low weight.

    In the big picture, yes. But we aren't sticking around to wait for it to cool back down into water. It's being ejected not as hot water but as an H2+O fueled fireball. Superheated steam just isn't going to be as much temperature..


  6. In essence you're just talking about a thermal rocket engine, like a NERVA. You heat some substance in a reactor chamber and spew it out. The hotter the better and the lighter the ejected particles the better. As such water is not a terrible choice, but H2 would be way better. Not to mention that if you have enough energy to split water you could just split the H2 into H radicals which are the best reaction mass without delving into subatomics.

    Well, not exactly.

    The electricity primarily only serves to split the water into H2 and O, and be a source of ignition. As a result some heat will be added, yes, so to that extent you are right. But now we have hot HHO gas, it explodes and we have typical chemical rocket action from that reaction.

    Using electrolysis to pre-separate the gas and have the H2+O reaction later on is different in that we would have isolate and store both H2 and O (storing them together would be highly unstable and probly eventually just turn back to water). It would work better if the power source is lower and steady, but now you have a water tank, electrolysis setup, gas tanks, etc. I want to explore the option that if the power is available, can we just do it all at once and make water explode?


  7. well, it's kinda like it's supercavitating through the atmosphere. a plate at the very nose could be used to increase the size of the air bubble to include most of the craft, and to deflect the air bubble around, much like concepts for steering in supercavitating water..


  8. This is a concept for a rocket engine which uses water as fuel. This engine assumes that you have a large quantity of electricity available.

    It's actually pretty simple. Instead of doing electrolysis then combusting the HHO, a huge arc of electricity does both at the same time. Basically with enough input energy the water literally explodes.

    Whatever water in the area doesn't explode will turn into superheated steam, which also expands in volume and serves to increase the air density of the output area.

    Depending on the source of electricity this likely will not be the most weight efficient approach, but it should be very simple and clean to refuel. Also the output is only heat and water.

    optionally, other fuels given the same approach may have more bang for the buck. like metal pellets or some other liquids which contain a lot of potential energy but are not normally combustible.


  9. Eh. I don't really like the food idea either.

    With the o2 you've already added a time limit on how long the mission can last, with more time costing more weight. Adding food is just more of the same.. so the gameplay wouldn't change but now there's more resources to manage. It's an extra layer of complication that just accomplishes the same thing. It also isn't nearly as pressing a matter as having air to breathe!

    just consider it nutrient air. problem solved. :P


  10. eh. I think it's a little overcomplicated.. I like it more simplistic.

    As it is now I'm just going to add every single part every time because:

    -why not. I'm spending the time on a sat.

    -I don't know which ones I might not need.

    -I just want map no matter how terrible my orbit, so I'll throw everything at it.

    I want to treat it like kethane, ISA, etc. Is the dish part on there? OK DONE.


  11. I like the separatron idea. They are small enough and useful as a backup plan if things go wrong with the engines. Still waiting on question about adding other mod parts to cfg..

    I have another suggestion.. the right click menu in VAB is still bugging me. Is there a way to change it so you have to mouse over and hit a key? Much like the procedural wings/tanks interface. This way you don't have accidental menu in the face.


  12. I love the new lights.. but uh is there a way to disable the right-click menu popup in VAB? I keep accidentally bringing the menu up, and right clicking the part again doesn't make the menu go away, have to click the x. but it's click-thru, so have to scroll off somewhere to find a safe place to click. It's actually really annoying.. the KAS bins are easy enough to miss, but the light ring is a big part the whole diameter of the craft, if i'm zoomed in it's actually pretty tough to right click and not get menu'd in the face!

    The presets work really well, I don't think it would be such a big deal to hit those at launch..

    Or perhaps there could be a separate icon or button in VAB somewhere to mess with them. Like the modular wings you mouse over the part and hit buttons on the keyboard to activate part adjustment.. there could be a menu button. Just right-click is killing me, need that to be cam adjustment only.

    Thanks!