Mars Airplane Thermoelectric Carbon Dioxide Propellant Generator Paul Rosensteel Michael McVey Advisor: Dr. Robert Ash

NASA ARES (Aerial Regional- Scale Environmental Survey)

Mars Airplane Propulsion Unit

Problem Statement Develop a test bed for thermoelectric device application and viability as a renewable source of solid CO2 production for use as a propellant on the NASA ARES (Aerial Regional-Scale Environmental Survey ) Vehicle

Mars Conditions Atmosphere: 95.32% carbon dioxide, 2.7% nitrogen, 1.6% argon, 0.13% oxygen and 0.07% carbon monoxide with variable water content. Pressure: 4.56 torr (0.006 atm). Gravity: 37.95% (3.711m/s 2 ) of Earth’s. Temperature: Average surface temperature is 210 K and ranges from 185 to 235 K at the middle latitudes.

Thermoelectric Device

Peltier Effect

Ultrasonic Distance Detector

Ultrasonic Device Schematic

Ultrasonic Sensor Circuit

Sensor Setup

Vacuum Chamber Setup

Measurements Chamber Pressure Chamber Temperature T H and T C of TE Device T R Heat Sink Temperature Dry Ice Layer Thickness – Range Detector Device Power

Experimental Data

Constant power of 10Watts applied. Constant chamber pressure of 5.8 Torr. No detected dry ice layer. Gas composition 98% CO 2, 2% misc. Q C = hA S ΔT = 0.069W COP =

Conclusions Improved experimental design setup. More robust equipment required. Dry ice production possible. Feasible propellant option.

Safety and Environmental Carbon Dioxide build up during testing. Handling of pressurized gas. Electrical shock hazard potential. Extreme cold exposure. No hazardous gases or chemicals. Recycling of Carbon Dioxide. Solar power energy use.

Improvements Higher capacity Peltier device. Chamber dimension: 1) Pressure Chamber 2) Smaller volume – 1100cm 3 vs. 0.1m 3 3) Thermal Isolation of connections Cooling method – Liquid Nitrogen

CO 2 Propulsion Questions and Answers