Design of Full-Ocean-Depth Self-Floating Sampler and Analysis of Factors Affecting Core Penetration Depth

Abstract

The hadal zone (ocean depths of 6 – 11 km) is one of the least-understood habitats on Earth because of its extreme conditions such as high pressure, darkness, and low temperature. With the development of deep-sea vehicles such as China’s 7000 m manned submersible Jiaolong, abyssal science has received greater attention. For decades, gravity-piston corers have been widely used to collect loose subsea-sediment long-core samples. However, the weight and length of the gravity sampler cables and the operating environment limit sampling capacity at full ocean depths. Therefore, a new self-floating sediment sampler with a spring-loaded auto-trigger release and that incorporates characteristics from traditional gravity-driven samplers is designed. This study analyzes the process by which a gravity-piston corer penetrates the sediment and the factors that affect it. A formula for obtaining the penetration depth is deduced. A method of optimizing the sampling depth is then developed based on structure design and parametric factor modeling. The parameters considered in the modeling include the sampling depth, balance weight, ultimate stress friction coefficient, dimensions of the sampler, and material properties. Thus, a new deep-sea floating parametric sampler designed based on virtual prototyping is proposed. Accurate values for all the design factors are derived from calculations based on the conservation of energy with penetration depth, analyses of the factors affecting the penetration depth, and analyses of the pressure bar stability. Finally, experimental data are used to verify the penetration-depth function and to provide theoretical guidance for the design of sediment samplers.

Journal

Journal ID (publisher-id): JOUC

Title: Journal of Ocean University of China

Publisher: Science Press and Springer (China )

ISSN (Electronic): 1672-5182

Publication date (Electronic): 02 September 2020

Publication date (Print): 01 October 2020

Volume: 19

Issue: 5

Pages: 1094-1102

Affiliations

¹School of Mechanical Engineering, Shandong University, Jinan 250061, China

²National Deep Sea Center, Qingdao 266237, China

³Institute of Marine Science and Technology, Shandong University, Qingdao 266237, China

⁴Science and Technology on Underwater Vehicle Laboratory, Harbin Engineering University, Harbin 150001, China

Author notes

*Corresponding authors: LIU Yanjun, E-mail: lyj111ky@ 123456163.com ; ZHANG Jianhua, E-mail: jhzhang@ 123456sdu.edu.cn

Article

Publisher ID: s11802-020-4276-9

DOI: 10.1007/s11802-020-4276-9

Copyright statement: Copyright © Ocean University of China, Science Press and Springer-Verlag GmbH Germany 2020.

License:

The copyright to this article, including any graphic elements therein (e.g. illustrations, charts, moving images), is hereby assigned for good and valuable consideration to the editorial office of Journal of Ocean University of China, Science Press and Springer effective if and when the article is accepted for publication and to the extent assignable if assignability is restricted for by applicable law or regulations (e.g. for U.S. government or crown employees).

Product

Self URI (journal-page): https://www.springer.com/journal/11802