Aerodynamic and Thermal Considerations for an Antarctic Ice Penetrator

Abstract

The Seismo-Geodetic Ice Penetrator (SGIP) is a helicopter-deployed kinetic penetrator designed to deliver a Global Navigation Satellite System (GNSS) and geodesy-grade seismometer to the Ross Ice Shelf (RIS) in Antarctica such that the seismometer becomes buried 2 m deep in the ice, ensuring coupling with the ice shelf. This vehicle provides a means to obtain data informative of ocean-atmosphere-ice dynamics that has historically been challenging to gather due to the remoteness and extreme environment of the RIS.

In order to ensure an appropriate impact velocity and angle, SGIP’s aft-body must be sized to produce a drag force that results in a target terminal velocity of 42 m/s while remaining aerodynamically stable. A finite element flow simulation in SolidWorks and analytical stability calculations are applied to ensure that these requirements are met. Analytical predictions are compared with experimental data from wind tunnel testing and two full-scale drop tests in Alaska. The penetrator must be thermally insulated so that internal electronics are kept within their operating temperature range without melting the surrounding ice. A COMSOL finite element heat transfer model is used to inform the design of thermal insulation for the system to meet these requirements.