TEAM JUPITER. KATHERINE BLACKBURN· SETH BURLEIGH · JOSEPH TRAN. LaAces 2009-2010 Pre-Preliminary Design Review. MISSION GOAL.
KATHERINE BLACKBURN· SETH BURLEIGH · JOSEPH TRAN
Pre-Preliminary Design Review
Our goal is to investigate the causes of atmospheric electrical conductivity as a function of altitude. The launch will take place at the Columbia Scientific Balloon Facility (CSBF), in Palestine, Texas on May 25, 2010.
Figure 1- Altitude as a function of conductivity. Most of the potential drop of the atmosphere occurs near the surface. Adapted from Reference 2.
Figure 2 – There is a quasi-sinusoidal behavior of the electrical field with respect to time as shown above. Adapted from Reference 2.
THEORY OF OPERATION: VOLTAGE DECAY
Equation 3 – Conductivity vs. exponential fit time constant
Equation 4 – Capacitor current vs. combined Gerdien and measurement capacitance and change in outer-inner cylinder voltage
Equation 5 – Conductivity
Equation 6 – Theoretical cylindrical capacitor capacitance
Equation - Gerdien capacitor current given V (outer voltage- inner voltage), L (length), a (conductivity), b(inner radius), and a (outer radius)
Equation - Critical mobility - the minimum ion mobility (drift velocity/electric field) that will be captured by the gerdien capacitor
ION CURRENT, BIAS VOLTAGE
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