Dynamic Effect Of Magnetic Resistance During Mars Descent

Mars atmosphere is thinner than earth as its average atmospheric pressure is only 700Pa[1], it’s difficult to make deceleration in the Mars because thinner atmosphere produces smaller resistance. Mars exploration vehicle has to carry more propellant for adequate flight braking force. As a result, the launch mass of Mars exploration vehicle becomes heavier, which leads to the bigger propulsion of the carrier rocket. Numbers of Mars exploration ideas can’t be achieved because of the limited technology. The American Mars aircraft makes the orbit-braking propellant reduction by use of air-braking in Mars circular orbit. The air-braking is the technology which decelerates the aircraft by Mars atmospheric resistance at periapsis, which lowers the altitude of apoapsis and leads the aircraft into a circular orbit.This article makes an estimation of Mars atmosphere. There will be a strong interaction between the high-speed aircraft and Mars atmosphere, as the velocity of aircraft is much higher than Mars sound, there will be a bow shock of high Mach(the Mach number is about 20) forming in front of the aircraft. To make the propellant reducing as well as deceleration adding, we can make use of the interaction between a strong magnetic field and high-speed plasma to get the resistance, the drag is adding with the help of magnetic field, which is called magnetic resistance in this article.Based on the effect of magnetic resistance, this article proposes the idea of supplying the extra drag with magnetic diploe field during Mars descent. The plasma in the bow shock would be captured by the magnetic diploe field added to the craft. As a result, there is a magnetic bubble generating which moves along with the craft. The exchange of momentum between neutral airflow and plasma generates the drag, which helps slow down the craft through the magnetic field.This article designs a system of magnetic resistance, which adds a strong magnetic diploe field to the aircraft by magnets. It’s found that magnetic resistance could offer the force of 103N(level) when the surface magnetic field intensity gets 1T. With the help of magnetic resistance, the craft gets a lower Mach number at the same altitude of parachute deployment. The velocity of craft plays an important role in the parachute deployment because the reliability of parachute deployment will enhance under a low velocity. As a result, magnetic resistance may provide great help to the security and reliability of Mars EDL as well as good reference of deceleration in the future Mars exploration.