Abstract

For effective research and teaching it is vital to understand the physics of balloon flight. Starting with the basic equations of motion in a viscous fluid a relationship is obtained relating the ascent velocity to the balloon size and gas parameters, to the atmospheric parameters, and to the fluid flow viscosity parameters (coefficient of drag and Reynolds number). In addition, the differential thermal heat transfer is important for understanding lift particularly around the tropopause region where the ascending balloon gas is expanding (and cooling) while the external stratospheric temperature is increasing. The detailed equations of motion are fundamentally based on the more complex thermodynamic and fluid dynamic equations with aerodynamic forces and balloon shape changes from a sphere. Theoretical data are compared with several balloon flights where a special internal probe within the balloon is used to measure heat transfer. A dynamic Excel database is available based on these equations and available constants to help predict and understand the balloon flight and the atmospheric environment. From the physical understanding of the balloon physics the ascent rates, fluid properties, and heat transfer can be used for making new measurements and improving STEM teaching.

How to Cite:

Voss, H. D., Ramm, N. A. & Dailey, J. F., (2012) “Understanding High-Altitude Balloon Flight Fundamentals”, Academic High Altitude Conference 2012(1), 74–83. doi: https://doi.org//ahac.8327