Float Altitude Calculator

The Float calculator takes the inputs of the stretched volume of one balloon, the mass of both balloons, and the mass of the payload and outputs the total neck lift needed to achieve different float altitudes assuming the volume reaches 95% of both balloon’s capacity (graph seen below).  The float altitude is based on the idea of balloon reaching neutral buoyancy at high altitudes.  As the balloons’ altitude increases, the atmospheric density of air decreases.  This results in a lower effective buoyant force because the lighter helium air enclosed inside the balloon displaces less fluid (air).  The float calculator takes this factor into consideration as well factors such as the temperature and the contamination of helium.  More detailed information on the float calculator can be seen in the report.

Sources

Scholarly Articles:

High-Altitude Gas Balloon Trajectory Prediction

  • Author: Sobester
  • DOI:  10.2514/1.J052900
Websites:

NASA Earth Atmospheric Model

Hypsometric Pressure

Barometric Formula

USI Engineering Faculty Support:

Special thanks to Dr. Glen Kissel and Dr. Brandon Field

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