scholarly journals Orthogonal experimental research on the structural parameters of a novel drill bit used for ice core drilling with air reverse circulation

2019 ◽  
Vol 65 (254) ◽  
pp. 1011-1022 ◽  
Author(s):  
Pinlu Cao ◽  
Qi Zhao ◽  
Zhuo Chen ◽  
Hongyu Cao ◽  
Baoyi Chen
Keyword(s):  
Structural Parameters ◽  
Ice Core ◽  
Influential Factor ◽  
Dominant Factor ◽  
Orthogonal Experimental Design ◽  
Drill Bit ◽  
Entrainment Ratio ◽  
Core Drilling ◽  
Helical Angle ◽  
Reverse Circulation

AbstractA new type of ice core drill bit, designed with a vane swirler, was developed for ice core drilling with air reverse circulation. An orthogonal experimental design method was employed to investigate the effects of the swirler structure parameters on the reverse circulation performance of the drill bit including helical angle, number of blades, blade length and blade central angle, etc. The entrainment ratio was used to evaluate the reverse circulation effectiveness of the drill bit. The results show that the helical angle is the dominant factor regardless of whether or not the flushing nozzles are part of the design of the drill bit. The number of blades is the least important factor for the drill bit designed with the flushing nozzles (referred to as drill bit I), while the outlet area of the swirling slot is the least influential factor for the drill bit without flushing nozzles (referred to as drill bit П). In addition, the appearance of the ice core has a certain effect on the air reverse circulation for both drill bits. Within the ranges of this study, the optimal structure of the drill bit was determined based on the range analysis of the orthogonal design.

scholarly journals Experimental and Numerical Analysis of Flow Behavior for Reverse Circulation Drill Bit with Inserted Swirl Vanes

Geofluids ◽  
2022 ◽  
Vol 2022 ◽  
pp. 1-13
Author(s):  
Cheng Yang ◽  
Jianliang Jiang ◽  
Bo Qi ◽  
Guoqing Cui ◽  
Liyong Zhang ◽  
...  
Keyword(s):  
Cfd Simulation ◽  
Structural Parameters ◽  
Flow Behavior ◽  
Experimental Tests ◽  
Maximum Error ◽  
Influential Factors ◽  
Drill Bit ◽  
Entrainment Ratio ◽  
Helical Angle ◽  
Reverse Circulation

A swirling drill bit designed with an integrated vane swirler was developed to improve reverse circulation in down-the-hole hammer drilling. Its entrainment effect and influential factors were investigated by CFD simulation and experimental tests. The numerical results exhibit reasonable agreement with the experimental data, with a maximum error of 13.68%. In addition, the structural parameters of the swirler were shown to have an important effect on the reverse circulation performance of the drill bit, including the helical angle and number of spiral blades, swirler outlet area, and the flushing nozzles. The optimal parameters for the swirling drill bit without flushing nozzles include a helical angle of 60°, four spiral blades, and the area ratio of 2, while it is about 30°, 3, and 3 for the drill bit with flushing nozzles. Moreover, the entrainment ratio of the drill bit without flushing nozzles can be improved by nearly two times compared with one with flushing nozzles under the same conditions.

scholarly journals A new portable ice-core drilling machine: application to tephra studies

1998 ◽  
Vol 44 (146) ◽  
pp. 179-181 ◽  
Author(s):  
J. M. Casas ◽  
F. Sàbat ◽  
J. M. Vilaplana ◽  
J. M. Parés ◽  
D. M. Pomeroy
Keyword(s):  
Ice Core ◽  
Portable Device ◽  
Drill Bit ◽  
Drilling Machine ◽  
Tephra Layer ◽  
The South ◽  
Core Drilling

Abstract A new portable device for ice-core drilling, specially designed for thin tephra-layer sampling, was tested on the South Shetland glaciers during the 1994-95 Antarctic summer. The machine is based on a combination of the standard paleomagnetism drilling machine and a specially built drill-bit designed for ice-coring.

Theory calculation and testing of air injection parameters in ice core drilling with air reverse circulation

Polar Science ◽  
2018 ◽  
Vol 17 ◽  
pp. 23-32 ◽  
Author(s):  
Pinlu Cao ◽  
Miaomiao Liu ◽  
Zhuo Chen ◽  
Baoyi Chen ◽  
Qi Zhao
Keyword(s):  
Ice Core ◽  
Air Injection ◽  
Core Drilling ◽  
Injection Parameters ◽  
Reverse Circulation ◽  
Theory Calculation

scholarly journals Air reverse circulation at the hole bottom in ice-core drilling

2019 ◽  
Vol 65 (249) ◽  
pp. 149-156 ◽  
Author(s):  
ZHENGYI HU ◽  
PAVEL TALALAY ◽  
ZHICHUAN ZHENG ◽  
PINLU CAO ◽  
GUITAO SHI ◽  
...  
Keyword(s):  
High Efficiency ◽  
Ice Core ◽  
Ice Cores ◽  
Test Results ◽  
Core Drilling ◽  
Low Energy Consumption ◽  
Reverse Circulation ◽  
Drilling System ◽  
Conventional Drilling ◽  
Hole Bottom

ABSTRACTIce-core drilling to depths of 200–300 m is an important part of research studies concerned with paleoclimate reconstruction and anthropogenic climate change. However, conventional drilling methods face difficulties due to firn permeability. We have developed an electromechanical ice-core drill with air reverse circulation at the hole bottom. We believe that the new drilling system will recover ice cores faster than shallow auger drills, with high efficiency and low energy consumption. The theoretically estimated up-hole speed of the airflow should be not <7.7 m s−1 to allow proper removal of ice cuttings from the borehole bottom. The computer simulation and test results showed that the design of the new ice-coring drill is feasible. The maximum allowed penetration rate depends by square law on airflow.

scholarly journals A new portable ice-core drilling machine: application to tephra studies

1998 ◽  
Vol 44 (146) ◽  
pp. 179-181
Author(s):  
J. M. Casas ◽  
F. Sàbat ◽  
J. M. Vilaplana ◽  
J. M. Parés ◽  
D. M. Pomeroy
Keyword(s):  
Ice Core ◽  
Portable Device ◽  
Drill Bit ◽  
Drilling Machine ◽  
Tephra Layer ◽  
The South ◽  
Core Drilling

AbstractA new portable device for ice-core drilling, specially designed for thin tephra-layer sampling, was tested on the South Shetland glaciers during the 1994-95 Antarctic summer. The machine is based on a combination of the standard paleomagnetism drilling machine and a specially built drill-bit designed for ice-coring.

THE FACTORS THAT CAUSE THE LOSE OF ABILITY IN USING SUNDANESE OF ENGLISH LITERATURE STUDENTS IN UNIVERSITAS GUNADARMA

2018 ◽  
Vol 6 (1) ◽  
pp. 1-9
Author(s):  
Pradheka Aria Rangga
Keyword(s):  
Qualitative Method ◽  
Heritage Language ◽  
Social Economic ◽  
English Literature ◽  
Language Shift ◽  
Influential Factor ◽  
Demographic Factor ◽  
Dominant Factor ◽  
Political Factor ◽  
Data Source

In sociolinguistics, there is a phenomenon in which a community stops using their parent’s heritage language by making the use of the language in which they are located or stay as a mean of communication, it is called as a language shift. In this research, it aims to find out the factors that affected the students whose parents originated from Sunda not interested to learn their parent’s heritage language. Moreover, it aims to find out the most dominant factor that affected the students not interested to learn their parent’s heritage language. This research used the qualitative method and the data source comes from the students of English literature in Universitas Gunadarma. The result of this research shows the factors that affected the students not interested to learn their parent’s heritage language such as social, economic, and political factor, demographic factor, attitudes and values factors, education factor, migration factor, and bilingual or multilingual factors. Furthermore, education factor is assumed as the most dominant or influential factor to the students not interested to learn their parent’s heritage language, because all of the students choose agree to the education factor.

scholarly journals Centennial mineral dust variability in high-resolution ice core data from Dome C, Antarctica

2012 ◽  
Vol 8 (2) ◽  
pp. 609-623 ◽  
Author(s):  
F. Lambert ◽  
M. Bigler ◽  
J. P. Steffensen ◽  
M. Hutterli ◽  
H. Fischer
Keyword(s):  
High Resolution ◽  
Southern Ocean ◽  
Mineral Dust ◽  
Ice Core ◽  
Principal Component ◽  
Dominant Factor ◽  
Core Data ◽  
The Past ◽  
Dust Flux ◽  
Soluble Calcium

Abstract. Ice core data from Antarctica provide detailed insights into the characteristics of past climate, atmospheric circulation, as well as changes in the aerosol load of the atmosphere. We present high-resolution records of soluble calcium (Ca2+), non-sea-salt soluble calcium (nssCa2+), and particulate mineral dust aerosol from the East Antarctic Plateau at a depth resolution of 1 cm, spanning the past 800 000 years. Despite the fact that all three parameters are largely dust-derived, the ratio of nssCa2+ to particulate dust is dependent on the particulate dust concentration itself. We used principal component analysis to extract the joint climatic signal and produce a common high-resolution record of dust flux. This new record is used to identify Antarctic warming events during the past eight glacial periods. The phasing of dust flux and CO2 changes during glacial-interglacial transitions reveals that iron fertilization of the Southern Ocean during the past nine glacial terminations was not the dominant factor in the deglacial rise of CO2 concentrations. Rapid changes in dust flux during glacial terminations and Antarctic warming events point to a rapid response of the southern westerly wind belt in the region of southern South American dust sources on changing climate conditions. The clear lead of these dust changes on temperature rise suggests that an atmospheric reorganization occurred in the Southern Hemisphere before the Southern Ocean warmed significantly.

scholarly journals A hot-water ice-coring drill

2000 ◽  
Vol 46 (153) ◽  
pp. 341-345 ◽  
Author(s):  
H. Engelhardt ◽  
B. Kamb ◽  
R. Bolsey
Keyword(s):  
Ice Core ◽  
Ice Cores ◽  
Hot Water ◽  
New Method ◽  
Core Drilling ◽  
Water Ice ◽  
Water Jets

AbstractA new method of ice-core drilling uses an annulus of hot-water jets to melt out a cylindrical ice core. This lightweight device used in combination with a fast hot-water drill can quickly obtain ice cores from any depth.

scholarly journals The Berkner Island (Antarctica) ice-core drilling project

2007 ◽  
Vol 47 ◽  
pp. 115-124 ◽  
Author(s):  
Robert Mulvaney ◽  
Olivier Alemany ◽  
Philippe Possenti
Keyword(s):  
Melting Point ◽  
Ice Core ◽  
Ice Sheet ◽  
Austral Summer ◽  
Core Drilling ◽  
Drilling Operation ◽  
Drilling Technology ◽  
Pressure Melting ◽  
Small Team ◽  
Drilling Project

AbstractWe describe a project to retrieve a 948m deep ice core from Berkner Island, Antarctica. Using relatively lightweight logistics and a small team, the drilling operation over three austral summer seasons used electromechanical drilling technology, described in detail, from a covered shallow pit and a fluid-filled borehole. A basal temperature well below pressure-melting point meant that no drilling problems were encountered when approaching the bed and the borehole penetrated through to the base of the ice sheet, and sediment was retrieved from beneath the ice.

scholarly journals Perspectives for development of ice-core drilling technology: a discussion

2014 ◽  
Vol 55 (68) ◽  
pp. 339-350 ◽  
Author(s):  
P.G. Talalay
Keyword(s):  
Low Temperature ◽  
Ice Core ◽  
Modern Technology ◽  
Swiss Alps ◽  
Drilling Fluids ◽  
Core Drilling ◽  
The Core ◽  
Drilling Technology ◽  
Brittle Zone ◽  
Louis Agassiz

AbstractMore than 170 years ago, Louis Agassiz, one of the creators of glacial theory, made his first attempt to drill into the bed of Unteraargletscher, Swiss Alps. Since that time, various systems for thermal and mechanical drilling have been designed especially for boring into ice, and some conventional drill rigs been adopted for ice coring. Although contemporary ice-drilling knowledge and techniques are now familiar, there remain many problems to be solved by advanced modern technology. Specific challenges related to improving old drilling methods and developing new emerging technologies include: (1) identification of depth limitation of ‘dry’ drilling; (2) improvement of casing; (3) searching for the new environmentally friendly low-temperature drilling fluids; (4) reliable elimination of sticking drills; (5) improvement of core quality in the brittle zone; (6) additional core sampling from borehole walls after the core has been drilled; (7) obtaining oriented core; (8) designing automation drilling systems; (9) developing rapid-access drills. Possible ways of solving these problems are presented below.

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