Saturday, 15 October 2011

Research: Propulsion System

I've been looking at various websites about different possible methods of intergalactic propulsion and stumbled across some very interesting things. The diversity of the ideas is really quite astonishing!

Currently for all of our expeditions to space we use rocket propulsion; a technology that has existed since fireworks were invented in ancient China! It's literally the same thing in principle, the numbers are just much bigger and the goal is to not have the thing you're lifting blow up... Otherwise they're essentially the same.

The difficult part of space travel at the moment is leaving Earth. Once you're in space the resistance is so little that you can move around using relatively little fuel. The only method at the moment is using rockets. SpaceX have been developing improved types of rocket that are considerably more efficient to launch, but still fair from being practical in the truly long-term. Non-the-less, definitely worth a look:




The falcon 9 uses an ingenious configuration of 9 Merlin engines for thrust, and is the worlds most powerful gas generator cycle kerosine engine and can even tolerate the failure of an engine.



Using 3 separate cores with the same 9x merlin engine configuration, the Falcon Heavy is a rocket currently in development at SpaceX and provides lift equal to that of fifteen 747 engines at full power. This allows for the transportation of extremely heavy loads into space.

However, igniting tonnes of fuel at the back end of a rocket enough to push it up into orbit is incredibly inefficient! As you might expect... The huge rockets that you see on launch pads that are fired into space are in fact simply enormous fuel tanks. More than 90% of the mass of the rocket is fuel... So already I know I certainly don't want to have anything to do with that in my series. No no no... Besides, blowing up stuff at the back of a stick is fairly boring on the sciency end of things.

Once you have your craft in space, away from the resistances and gravity of Earth, you can move around much more efficiently. Let's have a look at some of the options!

An engine currently in development at NASA is the plasma engine named the VASIMR (VAriable Specific Impulse Magnetoplasma Rocket) could be a very efficient way of traveling through space.




I apologize for the patronizing video, but sadly the video I wanted to link has been blocked in the UK. I believe I can still link it for other people to view outside the UK but if you are in the UK, the following will probably be a blocked video. The above video does a fairly decent job of explaining what the engine is and does.


The basic concept is that the material is ionized and heated into a plasma state (like a super microwave), which respond extremely well to magnetic forces, and then uses magnetic fields to accelerate the particles out of the back of the engine to generate thrust. The concept is very similar to that of a rocket, but much more efficient.


The current main drawback of the technology is the lack of thrust it generates, currently not capable of generating enough to achieve orbit. Once in orbit however, the lack of resistance in space mean that acceleration is cumulative (you don't slow down). So over time, the engine would generate enormous velocities.

The strengths of the system, is the efficiency. VASIMR uses much less fuel than regular rockets, and the fuel for the plasma can be various commonly found elements such as hydrogen. Also, the use of magnetic fields could be modified to not only propel the craft but also to protect the crew from radiation... Very practical!

Efficient as the engine is, and will be it would still take an enormous amount of time to travel to even the nearest star system. So, even if this is the propulsion system I choose for the ship, additional things will be needs for inter-stellar travel.

I'll take a look at other options in another post!

Matty out.

No comments:

Post a Comment