Supersonic Laser-Propelled Rockets

Laser Ablation – Efficiency& Thrust of Regular Gas Blasting Rockets

A novel way has been discovered in using laser ablation to provide additional acceleration which can be done by using it to increase the efficiency and thrust of regular gas blasting rockets. A team of Russian scientists lead by Yuri Rezunkov at the Institute of Optoelectronic Instrument engineering have proposed a novel idea to accelerate a spaceship while it is in flight, firing a ground based laser up on its backside.

The concept of the new technique utilises a plasma flow which is caused by laser ablation that tends to increase the exhaust efficiency of a traditional rocket propulsion system, which would theoretically accelerate an aircraft beyond March 10. Scientists as well as scientist fiction writer had dreamt of aircrafts that would be propelled by beams of light instead of the conventional fuels and an advanced method of improving the thrust generated by laser propulsion systems will now bring them towards the vision of their dream.

A process known as laser ablation which is a high powered focused laser beam would strike the surface of an object in space burning off the surface material thereby producing a plume of charged plasma particles which will enable the thrust, a process which has been considered as a means to potentially blast space debris out of the earth orbit.

Laser At Remote Location Instead of Spacecraft

Inthis case, it will be seen as a means to provide additional thrust for spaceship without the need of having to carry primary energy supply on board the ship, i.e. the ship does not have to carry enough extra surface metal to burn off in the process of ablation.

Presently, the maximum speed limit is restricted by the amount of solid or liquid fuel which is carried and achieving higher speeds would mean more fuel to be burned, which needs to be carried by the craft that could cause inconvenience together with added space.

These loads can be reduced now with the use of laser, one that is located at a remote location instead of `on the spacecraft’, which could be used to provide the additional propulsive force. Various systems have been recommended which could produce such laser propulsion, one which would involve the process known as laser ablation wherein the pulsed laser beam tends to strike a surface, heats it up and burns of the material creating what is called a plasma plume.

Plasma Plume – Exhaust Generating the Extra Thrust

A column of charged particles then flow off the surface and the out flowing of that plasma plume essentially is the exhaust that generates the extra thrust needed to propel the spacecraft. The effectiveness is limited of the current laser propulsion, by factors which include the instability of supersonic gases when they flow through the gas nozzle and as the production of shock waves which choke the inlet of the nozzle thereby reducing thrust.

These effects could be reduced with the use of laser ablation plasma plume which is redirected with the potential of enabling flow close to the interior walls of the nozzle. Together with the ablation jet and supersonic gas flow through the nozzle, a significant improvement in the overall thrust can be found generated by the nozzle.