The Effect of Various Cosmic Ray Flux-Spectra on PDR Chemistry
Mass Driver PDR
Transcript of Mass Driver PDR
Mass Driver PDRFebruary 25, 2020
Mission Profile (Mars → Phobos)
● Launch windows are defined by phobos
position and tether sling spin up time
○ Phobos must be -29.033° from
Olympus Mons (right ascension)
○ Max turnover = 3 launches/sol
● Acceleration Profile
○ 4.77 km/s Launch Velocity
○ 4.47 km/s Velocity past
atmosphere
○ 2 G’s net
● Total Orbital Flight Time 14.69 hrs
Orbital Trajectory
ΔV (km/s) Time (hrs)
Launch 4.77 6.17
Burn 1 0.286 8.52
Burn 2 0.375 RNDVZ
Total 0.661 14.69
Considerations & Deviations
● Acceleration modification
○ Make time and distance shorter
○ Launch Velocity includes drag and rotation
● Orbital analysis
○ No perturbations
○ No eccentricity/inclinations
● Risk Assessment
○ If launch fails, more ΔV is required
○ If burn 1 fails, the taxi will return to Olympus Mons
○ If burn 2 fails, no return possibility without significant ΔV
Current Mass Driver Design
MagLev System
• Proven to handle loads of our magnitude (passenger trains)
• Allows us to more easily decelerate the cradle for reusability
• Located at the base of Olympus Mons
• Using Null-Flux Coils for Repulsive Levitation
Current Mass Driver Design
Important Parameters
• Track Length: 635 km
• Launch Duration: 4 minutes 14 seconds
• 2g constant acceleration
• F required,propulsion = 6.49 MN
• F required,levitation = 1.1 MN
Candidate Systems
- Propellant saved: 477 Mg
PropulsionForce required: 6.49 MN
Railgun
LevitationForce required: 1.11 MN
Coilgun Maglev
Linear Synchronous
Motor (LSM)
Linear Induction
Motor (LIM)
Wheels Suspended
Electromagnetic
Suspension (EMS)
Electrodynamic
Suspension (EDS)
Mass Driver Technology
z
x
Linear Induction Controller
• Set velocity that is needed to escape Mars(5.03
km/s) Moon(2.38 km/s)
• Sense the velocity of the taxi vs how fast it needs to
have been going
• Increase the current through the LIM to increase
acceleration to needed levels
Journal of Transportation
Force will increase linearly with an
increase in current
Martian Taxi Catching SystemCradle
Information
Mass 100 tons
Material Aluminum 6061
T6
Length 25 meters
Magnet Width 15 meters
Width 36 meters
Mass Driver Materials & Structural Analysis
Mass Driver
Parts
Materials
Rail (EDS system) Iron, Wrought or
Rhenium beams
Vacuum Casing Iron, Wrought
Magnets 15 Lanthanides
Scandium
Yttrium
Niobium Titanium
Structural Integrity Precautions for
Track
• Rounded edges to prevent
cracking
• FEA testing will be conducted
through multiple scenarios (G-
forces, heat, cooldown etc.).
Suggestions needed to increase
reliability.
Power Consumption
Mars The Moon
Peak Power
Consumption (GW)
30.1 13.5
Average Power
Consumption (GW)
14 6.6
Total Energy
Consumption (GJ)
3600 830
● Power consumption peaks at the Taxis top speed when drag force is at a maximum
● Power is stored in batteries and used when solar panels can no longer keep up with the
required power
● VVVF (Variable Voltage, Variable Frequency) power is provided to support the needs of
the MagLev
Power Production and Storage
Mars The Moon
Solar Panel Power (MW) 100 10
Solar Panel Area (km2) .56 .024
Total Mass (Mg) 5500 1100
● Solar Panels provide limited energy and
charge the batteries over the long
duration between sets of launches
● Batteries are capable of holding enough
energy to launch 3 Taxis consecutively
Human Considerations
Forward Acceleration
Backwards Acceleration
7G’s absolute max acceleration (at any given time), 2G’s max sustained
acceleration recommended
Mass Driver Thermal Management• Power Consumption: 30 MW that
needs to be dissipated via Heat
Sinks.
• Due to the amount of heat
generated, the rail will slowly
erode over time, so it has to be
liquid cooled.[1]
Thermal
Systems
(Mars)
Mass Volume Power
Heat Sinks 6.49 Mg 34,285.7
m3
Passive
Cooling
Liquid
Cooling for
the Rail
172.8 Mg 5.1 * 108
m3
230 MW
1. M. Johnson, P. Cote, F. Campo and P. Vottis, "Railgun Erosion Simulator," 2005 IEEE Pulsed Power Conference,
Monterey, CA, 2005, pp. 245-248.
Analysis of Aerodynamic Drag
Aerodynamic Effects
• Max Drag is around 53kN of
force
• Aerodynamic heating is 3.14
GW which would be less than
re-entry heating
• Further analysis is required
based on keeping the magnets
supercooled