Single fuel engines.

[kneggis]

Dear Forum,

I am trying to create an engine that runs on a single propellant.(just like they used to)

Mainly an electric one.

Is this possible?

And can you give me an example?

Thanks in advance.

[Flixxbeatz]

A few cfg tweaks and you're off to go.

Oh wait... All clear. I still see part.cfg files.

[kneggis]

Well maybe you can tell me what i need to tweak.

I tried simply removing the non-ElectricCharge propellant but then it just.

so, this was my final attempt of my tweaks.

Maybe you can tell me what i missed?

The only thing it tells me is that its electric charge deprived.

But its hooked up to a battery.

mass = 0.25

dragModelType = default

maximum_drag = 0.2

minimum_drag = 0.2

angularDrag = 2

crashTolerance = 7

maxTemp = 3600

MODULE

{

name = ModuleEngines

thrustVectorTransformName = thrustTransform

exhaustDamage = False

minThrust = 0

maxThrust = 50

heatProduction = 0

PROPELLANT

{

name = ElectricCharge

ratio = 12.0

}

(removed one propellant here).

atmosphereCurve

{

key = 0 4200

}

}

MODULE

{

name = FXModuleAnimateThrottle

animationName = colorAnimation

dependOnEngineState = True

responseSpeed = 0.5

}

}

Thanks in advance

Edited July 16, 2013 by kneggis

[Greys]

The mass of the fuel resource is used in calculating how much to consume at a given thrust value, if the mass of the fuel resource is zero that math cannot be done.

Resources without mass cannot produce thrust.

Electric_Charge has no mass.

For making a single fuel engine with any valid resource, just look at SRBs and change the resource they consume

[Kermunist]

IIRC the game uses the density of the resource, the ISP and the thrust to calculate how much of the resource it needs. As the density of electricity is zero, it needs an infinite amount, which it can't get. Hence it is deprived.

This is why you can't create thrust with just electricity. You might be able to work around the problem by adding a resource generator module to the part. You can then generate a propellant (which has mass) at the same speed the engine uses it.

[betaking]

what about monopropellant engines?

I've been wanting a stockalike monopropellant engine for a while.. would make it easier to build orbital ferries.

[Greys]

speaking outside KSP, any thruster that uses a single tank is a monopropellant, which means solid boosters are monopropellant rockets. KSP does not care what fuel it consumes in an engine to produce thrust, so long as that fuel has mass, if you added a mass value to electricity it would be a valid propellant. If you add a new resource called Bacon and it had a mass, it would be a valid propellant. Monopropellant engines have already been done so I can tell you with certainty that it works but do consider that MonoPropellant the resource is 20% less dense than LiquidFuel/Oxidizer, and takes up 25~% more space per unit. So you will need more of it to achieve the same dV and it will take up more space than the same amount of LF/O.

If you're cool with both of these, there is nothing prohibiting you from doing so.

(it should be noted that KSP's mechanics present a divide between Density, the mass of a unit of resource, and Volume Density, the amount of space a unit takes up, and as such creates an additional measure, Units per Cubic Meter which would then have a sum mass)

Edited July 16, 2013 by Greys

[kneggis]

I didnt know that!

Thanks alot.

I got it to work now!