Structure Design and Ice Core Breaking Simulation of Continual Air-reverse-circulation Ice Coring Drill

Abstract:

Ice cores contain vast amounts of paleoclimate and paleontological information. These are important for climate change and biological evolution from ancient times to modern times. How to acquire clean ice cores efficiently and quickly is an important issue for polar scientists.The continual air-reverse-circulation ice coring drill use a double-wall drill pipe to form a reverse circulation channel. The inner pipe provides a continuous channel for transporting the ice chips and cores from the bottom of the hole to the ice sheet surface.The drill can break the ice core by its breaker, and move the ice core continuously through the reverse circulation channel, so as to realize the continual coring. By using ABAQUS software, this paper analyzes the process of ice core breaking, use of XFEM fracture criterion and Explicit method, choose appropriate breaker size and center channel size, so as to get better effect of reverse circulation drilling.

Key words:ice drilling; structure design; numerical simulation; ice core breaking; reverse circulation