Paper VT-TuP8
The Titan Blimp

Tuesday, October 21, 2008, 6:30 pm, Room Hall D

The purpose of this project was to test the feasibility of an exploratory blimp in the harsh conditions present on Saturn’s largest moon, Titan. A blimp would possess significant advantages over satellites due to Titan’s enormously thick atmosphere, as well as over rovers due to the extremely cold temperatures that exist on the surface. These facts establish that a blimp with the flexibility to ascend and descend through the atmosphere and land on the surface would be the most practical exploration vehicle. An insulated pressure/vacuum chamber was constructed to house a simulated atmosphere of Titan. This vacuum chamber was constructed from a steel dollar-coin changer measuring 26” x 19” x 13”. The lid was sealed with an inch thick acrylic lid to allow for visible inspection as experimentation was run. Liquid nitrogen was poured into the chamber, and its evaporation created the -180ºC temperature of Titan’s surface, the 95% nitrogen gas composition of Titan’s atmosphere, as well as the 147kPa surface pressure. A 12-liter mylar balloon was placed inside the chamber and filled with cryogenic helium gas to generate buoyancy. RTD temperature probes were used in the chamber to measure the chamber temperature as well as the balloon temperature. Two pressure transmitters were also installed to measure the pressure of both the chamber and the balloon. These pressure transmitters as well as electric solenoid valves were connected to pressure controllers, which could then regulate the pressure of both the chamber and balloon simultaneously. A pressure control program was used in conjunction with a vacuum pump to simulate an ascent and descent through the Titan atmosphere, reaching simulated altitudes of 16km. A feasible balloon was successfully kept fully inflated through various pressure changes without exploding.