Numerical Investigation on the Evolution of Thin Liquid Layer and Dynamic Behavior of an Electro-Thermal Drilling Probe during Close-Contact Heat Transfer

• Published in: Applied sciences Vol. 11; no. 8; p. 3443
• Main Authors: Jeong, Chan Ho, Kang, Kwangu, Park, Ui-Joon, Lee, Hyung Ju, Kim, Hong Seok, Park, Jin-Yeong, Lee, Seong Hyuk
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.04.2021
• Subjects: Astrobiology; close-contact melting (CCM); Computational fluid dynamics; computational fluid dynamics (CFD); Contact melting; Drilling; electro-thermal drilling probe (ETDP); Energy balance; Energy equation; Experiments; Glaciers; Heat conductivity; Heat transfer; Mathematical models; Numerical analysis; rate of penetration (ROP); Simulation; Solidification; Solids; Temperature; thermal characteristics; Thin films
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app11083443

This study investigates the transient behavior of an electro-thermal drilling probe (ETDP) during a close-contact melting process within a glacier. In particular, the present work analyzes the effect of the tip temperature on the formation of molten thin liquid films and the subsequent rate of penetration (ROP) through numerical simulation. We used the commercial code of ANSYS Fluent (v.17.2) to solve the Reynolds-averaged Navier–Stokes equation, together with an energy equation considering the solidification and melting model. The ROP of the drilling probe is determined based on the energy balance between the heating power and melting rate of ice. As the results, the ETDP penetrates the ice through a close-contact melting process. The molten liquid layer with less than 1 mm of thickness forms near the heated probe tip. In addition, the ROP increases with the heated temperature of the probe tip.