Abstract

Stratospheric balloons are popular for scientific applications as they can carry heavy payloads to perform observations for a long duration. However, for practical applications, a major challenge is the control of the trajectories of the balloons as well as station keeping for a period of time due to severe weather condition such as strong wing at the stratosphere. In order to have a better control of the movement of a stratospheric balloon, we need to have a better understanding of the air flow drag acting on a typical stratospheric balloon. In this paper, numerical simulation studies using the Star CCM+, a computational fluid dynamics software, are carried out to investigate the air drag coefficients of a balloon in the stratosphere in tropical region. By analyzing the weather data provided by the local Meteorological Service for the past three years and considering the balloon size according to the payload capacity, the characteristic Reynolds numbers and flow regime are identified. Thereafter, numerical investigations are performed to study the air drag acting on a pumpkin-shaped stratospheric balloon under typical stratospheric weather conditions in tropical regions, which is justified by referring to the drag force acting on a sphere when a flow past it under those Reynolds numbers that is obtained by using the respective empirical and semi-empirical solutions obtained from experiments.

How to Cite:

Sun, Q., Lim, K., Lee, H. & Khoo, B., (2015) “Air Drag on a Stratospheric Balloon in Tropical Regions”, Academic High Altitude Conference 2015(1). doi: https://doi.org/10.31274/ahac.5572