Results 21 to 30 of about 182,598 (263)

Fluid simulation in a cyclone reverse circulation well washing device based on computational fluid dynamics

Energy Science & Engineering, 2019
This paper instructs the working principle of the well washing device and its parameter optimization in practical applications. A fluent fluid engineering simulation software was used to establish the calculation model of the bottom flow field. The fluid
Chun Sheng Wang, Lei Zhang
doaj   +1 more source

Sealing method and experimental study of large-diameter reverse circulation hole hammer [PDF]

E3S Web of Conferences
A reliable sealing structure is the key to achieving reverse circulation drilling technology for large- diameter reverse circulation down the hole hammers, and it is also a difficult point in the design of large- diameter reverse circulation down the ...
Liu Qi
doaj   +1 more source

Migration Characteristics of Boring Mud in Roadway Floor Anchor Wire Hole and Test in Coal Mine

Advances in Civil Engineering, 2021
Given the difficulty in drilling the anchor holes in the roadway floor of the coal mine, the characteristics of slag movement in the process of positive and negative circulation drilling are analyzed.
Hui Zhang, Weihai Han, Youlin Xu, Mengzhi Zhu, Zhanyang Liu, Zhenfeng Wang   +5 more
doaj   +1 more source

Determinants of reversible asynergy. The native coronary circulation. [PDF]

Circulation, 1975
To evaluate the influence of the native coronary circulation on the reversibility of asynergy, ventriculograms before and after sublingual nitroglycerin were performed in 51 patients with coronary artery disease and asynergy. The severity of stenotic lesions and caliber of the distal coronary vessels were determined by comparison with external catheter
V S, Banka, M M, Bodenheimer, R H, Helfant   +2 more
openaire   +2 more sources

EXTIRPATION AND REPLANTATION OF THE THYROID GLAND WITH REVERSAL OF THE CIRCULATION [PDF]

Science, 1905
n ...
Carrell, A., Guthrie, C. C.
openaire   +3 more sources

Spin-polarized vortices with reversed circulation

Physical Review A, 2022
We present the analysis of the structure of fermionic vortices with the spin-polarized core from a weak coupling limit to the unitary regime. We show the mechanism for the generation of the {\it reversed circulation} in the vortex core induced by an excess of majority spin particles.
Piotr Magierski, Gabriel Wlazłowski, Andrzej Makowski, Konrad Kobuszewski   +3 more
openaire   +2 more sources

High Coronary Collateral Circulation Increases Left Ventricular Reverse Remodeling Event in Patients with Chronic Ischaemic Heart Disease Underwent Coronary Artery Bypass Surgery

Majalah Kardiologi Indonesia, 2021
Background: Coronary collateral circulation (CCC) is linked to myocardial remodeling severity in patients with chronic ischaemic heart disease (IHD). However its effect on left ventricular reverse remodeling (LVRR) in patients with chronic IHD underwent ...
Ignatius Faizal Yuwono
doaj   +1 more source

Advanced Approaches to Depth Optimization in Large-Diameter Water Well Drilling in Mangystau Peninsula

Engineered Science
Providing a reliable water supply to rural areas of the Mangystau Peninsula requires the construction of large-diameter wells, often in challenging geological conditions.
Gulzada Umirova, Aidar Kuttybayev, Volodymyr Khomenko, Samal Muratova, Marian Biletskiy, Boranbay Ratov, Zaida Makhitova, Aigul Gusmanova, Nurbol Tileuberdi, Manshuk Sarbopeyeva, Oleksandr Kamyshatskyi, Ligang Zhang   +11 more
doaj   +1 more source

Optimum Design of Large-Diameter Reverse Circulation Drill Bit for Drilling Rescue Wells Using Orthogonal Experimental Method and CFD Simulation

Energies, 2023
Down-the-hole (DTH) hammer drilling with reverse circulation is a novel, mobile, high-speed drilling system suitable for the specific requirements of mine rescue. This technology can be applied to shorten the rescue time during mine accidents.
Kun Bo, Fangzhou Ji, Zhiqiang Zhao, Liming Fan, Maosen Wang   +4 more
doaj   +1 more source

Drilling technology and gas-liquid dual-circulation technique for large-diameter rescue boreholes in mines

Meitan kexue jishu
The construction of large-diameter rescue boreholes in mines faces challenges such as tight timelines, complex geological conditions, and high requirements for trajectory accuracy. To meet the needs for efficient and reliable hole formation under complex
Shijun HAO, Linjie WANG, Jiangpeng ZHAO, Bingyan SHI, Jinbao ZHANG, Jing ZHANG, Zhitong ZHU   +6 more
doaj   +1 more source