Concept design of linear-motor-accelerated projectile for nanoparticle dispersion in stratosphere

Abstract

Global warming is one of the most serious issues facing humans. The author has proposed dispersing calcite nanoparticles into the stratosphere to decrease solar irradiation without changing the earth’s longwave infrared emission. If we can disperse 3.5 × 107 tons of nanoparticles of average diameter 450 nm into the stratosphere, we may be able to decrease solar irradiation by 3%. According to the life time of nanoparticles in the stratosphere, we could decrease this irradiation by launching projectiles and dispersing 10 tons of nanoparticles 19 times per day from 100 launch sites located in the world. The previous work has shown the potential of the launch system; however, the actual length of the vacuum tunnel, the energy supply to the accelerator, and the flight trajectory of the projectile after being ejected obliquely from the vacuum tunnel have not been investigated. In this paper, a feasibility design of a projectile is introduced to disperse 10 tons of nanoparticles at an altitude of 30 km using a linear-motor accelerator. According to the simulation, a projectile weighing 15 tons can be accelerated up to 1000 m/s in a 34-km acceleration vacuum tunnel by using superconducting linear motors. When the projectile is launched at an altitude of 3500 m, it can reach an altitude of 30 km. By unfolding sailwings at that altitude, the projectile maintains a level flight during dispersal of the nanoparticles in the stratosphere. The energy required for the launch is 2.55 × 1010 J, and the maximum electrical power required is 0.8 GW. The energy cost for dispersing nanoparticles is small compared with other methods such as rockets and airplanes.