scholarly journals Effect of the structure of backward orifices on the jet performance of self-propelled nozzles

2020 ◽  
Author(s):  
Bi-Wei Fu ◽  
Si Zhang ◽  
Shao-Hu Liu
Keyword(s):  
Numerical Simulation ◽  
Energy Efficiency ◽  
Structural Parameters ◽  
Critical Component ◽  
Propulsive Force ◽  
Drilling Performance ◽  
Drilling Technology ◽  
Value Range ◽  
Energy Coefficient ◽  
Working Performance

Abstract Self-propelled nozzle is a critical component of the radial jet drilling technology. Its backward orifice structure has a crucial influence on the propulsive force and the drilling performance. To improve the working performance of the nozzle, the numerical simulation model is built and verified by the experimental results of propulsive force. Then the theoretical model of the energy efficiency and energy coefficient of the nozzle is built to reveal the influence of the structural parameters on the jet performance of the nozzle. The results show that the energy efficiency and energy coefficient of the backward orifice increase first and then decrease with the angle increases. The energy coefficient of forward orifice is almost constant with the angle increases. With the increase in the number and diameter, energy efficiency and energy coefficient of the forward orifice gradually decrease, but the backward orifice energy coefficient first increases and then decreases. Finally, it is obtained that the nozzle has better jet performance when the angle of backward orifice is 30°, the number of backward orifice is 6, and the value range of diameter is 2–2.2 mm. This study provides a reference for the design of efficiently self-propelled nozzle for radial jet drilling technology.

scholarly journals Influence of Vortex Finder Structure on Separation Performance of Double-Overflow Three-Product Hydrocyclones

Separations ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 79
Author(s):  
Yuekan Zhang ◽  
Jiangbo Ge ◽  
Lanyue Jiang ◽  
Hui Wang ◽  
Junru Yang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Experimental Research ◽  
Separation Efficiency ◽  
Structural Parameters ◽  
Separation Performance ◽  
Insertion Depth ◽  
Flow Field Characteristics ◽  
Vortex Finder ◽  
Fine Classification

In view of the difficulty of traditional hydrocyclones to meet the requirements of fine classification, a double-overflow three-product (internal overflow, external overflow and underflow) hydrocyclone was designed in this study. Numerical simulation and experimental research methods were used to investigate the effects of double-overflow flow field characteristics and structural parameters (i.e., internal vortex finder diameter and insertion depth) on separation performance. The research results showed that the larger the diameter of the internal vortex finder, the greater the overflow yield and the larger the cut size. The finest internal overflow product can be obtained when the internal vortex finder is 30 mm longer than the external vortex finder. The separation efficiency is highest when the internal vortex finder is 30 mm shorter than the external vortex finder.

scholarly journals Optimization of Hot-Water Drilling in Ice with Near-Bottom Circulation

Water ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 127
Author(s):  
Gaoli Zhao ◽  
Pavel G. Talalay ◽  
Xiaopeng Fan ◽  
Nan Zhang ◽  
Yunchen Liu ◽  
...  
Keyword(s):  
Technology Development ◽  
Hot Water ◽  
Drilling Process ◽  
Outlet Temperature ◽  
Experimental Conditions ◽  
Rate Of Penetration ◽  
Drilling Performance ◽  
Drilling Technology ◽  
Jet Nozzle ◽  
Lower Flow Rate

Hot-water drilling in ice with near-bottom circulation is more advantageous than traditional hot-water drilling with all-over borehole circulation in terms of power consumption and weight. However, the drilling performance of this type of drill has been poorly studied. Initial experiments showed that drilling with single-orifice nozzles did not proceed smoothly. To achieve the best drilling performance, nozzles with different orifice numbers and structures are evaluated in the present study. The testing results show that a single-orifice nozzle with a 3 mm nozzle diameter and a nine-jet nozzle with a forward angle of 35° had the highest rate of penetration (1.7–1.8 m h−1) with 5.6–6.0 kW heating power. However, the nozzles with backward holes ensured a smoother drilling process and a larger borehole, although the rate of penetration was approximately 13% slower. A comparison of the hollow and solid thermal tips showed that under the same experimental conditions, the hollow drill tip had a lower flow rate, higher outlet temperature, and higher rate of penetration. This study provides a prominent reference for drilling performance prediction and drilling technology development of hot-water drilling in ice with near-bottom circulation.

Advanced Reservoir Navigation System and Drilling Technology Maximizes Productivity and Drilling Performance in the Granite Wash - US Midcontinent

2011 ◽  
Author(s):  
Sandeep Shashikant Janwadkar ◽  
Mark G. Thomas ◽  
Steve A. Privott ◽  
Robert Tehan ◽  
Lisa Carlson ◽  
...  
Keyword(s):  
Navigation System ◽  
Drilling Performance ◽  
Drilling Technology

Vacuum Forming Refrigerator Inner Liner Structural Optimization

2011 ◽  
Vol 291-294 ◽  
pp. 1069-1073
Author(s):  
Wen Bin Su ◽  
Xiang Bing Sun ◽  
Tao Li ◽  
Bao Jian Liu
Keyword(s):  
Numerical Simulation ◽  
Structural Optimization ◽  
Structural Parameters ◽  
Forming Process ◽  
Significance Level ◽  
Orthogonal Experiments ◽  
Combination Scheme ◽  
Vacuum Forming ◽  
Validation Experiment

Thickness thinning is the principal quality problem in the vacuum forming process of the refrigerator inner liner. In this paper, the structural parameters of refrigerator inner liner were analyzed based on orthogonal experiments and numerical simulation. Optimized structural parameters combination scheme and the significance level of structural parameters to thickness were obtained by analyzing the results of orthogonal experiments. Validation experiment results shown that the quality of refrigerator inner liner based on the optimized structural parameters combination scheme improved effectively.

scholarly journals Experimental Research and Numerical Simulation of Ejector Precipitator in a Fully Mechanized Mining Face

2020 ◽  
Vol 45 (11) ◽  
pp. 9815-9833
Author(s):  
Guodong Zhai ◽  
Wentao Zhang ◽  
Yaozong Li ◽  
Xinghao Lu ◽  
Wenyuan Hu
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Negative Pressure ◽  
Coal Dust ◽  
Structural Parameters ◽  
Dust Concentration ◽  
Dust Removal ◽  
Measuring Point ◽  
Mining Face ◽  
Supply Water

AbstractIn order to effectively reduce the coal dust concentration in a fully mechanized mining face, this research used laboratory experiment, numerical simulation, and field test to conduct an in-depth exploration of the ejector precipitator installed at the low-level caving coal hydraulic support. Firstly, through the experimental platform in the laboratory, the dust removal effect of the nozzle with different structural parameters was tested, and the 3D particle dynamic analyzer was adopted to verify its atomization characteristics; then, the structural parameters corresponding to the nozzle in the best test results were obtained. Secondly, by using Fluent, the negative pressure flow field in the ejector barrel was numerically simulated. The results indicated that when the pressure of supply water was 12 MPa, the negative pressure value formed in the flow field was the lowest and the inspiratory velocity was the largest, which was conducive to dust removal. Finally, the tests of liquid–gas ratio and dust removal ratio were carried out in a fully mechanized mining face. The results showed that when the nozzle specification recommended by the experiment and the pressure of supply water recommended by the numerical simulation were used, the removal ratios of the total coal dust and the respirable coal dust were 89.5% and 91.0%, respectively, at the measuring point of the highest coal dust concentration. It indicates that the ejector precipitator has a good application effect in reducing the coal dust concentration in a fully mechanized mining face and improving the work environment of coal mine workers.

scholarly journals Numerical Simulation of Conical Pick Cutting Arc Rock Plate Fracture Based on ANSYS/LS-DYNA

2020 ◽  
Vol 2020 ◽  
pp. 1-16 ◽  
Author(s):  
Zhiwen Wang ◽  
Qingliang Zeng ◽  
Zhenguo Lu ◽  
Lirong Wan ◽  
Xin Zhang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Cutting Force ◽  
Structural Parameters ◽  
Cutting Parameters ◽  
Rock Breaking ◽  
Central Axis ◽  
Plate Height ◽  
Conical Pick ◽  
Cutting Angle ◽  
Cutting Point

The new method of rock breaking based on the combination of circular sawblade and conical pick was proposed to improve the effectiveness of hard rock breaking. The numerical simulation method was applied to research the conical pick cutting arc rock plate by ANSYS/LS-DYNA. The conical pick cutting arc rock plate numerical simulation model was established to research the influence of arc rock plate structural parameters and cutting parameters on cracks formation and propagation of the arc rock plate and the cutting force in the process of conical pick cutting arc rock plate. The amount of cracks is positively correlated with arc rock plate thickness, the cutting speed, and distance of cutting point to arc rock plate central axis and negatively correlated with the cutting angle. The mean peak cutting force is positively correlated with the thickness of arc rock plate and the distance of cutting point to arc rock plate central axis; however, it is negatively correlated with the arc rock plate height and width and cutting angle of conical pick. The simulation results can be used to predict the conical pick work performance with various cutting parameters and structural parameters.

Optimization Design of Agricultural Fans Based on Skewed-Swept Blade Technology

2019 ◽  
Vol 35 (2) ◽  
pp. 249-258
Author(s):  
Tao Ding ◽  
Lumeng Fang ◽  
Ji-Qin Ni ◽  
Zhengxiang Shi ◽  
Baoming Li ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Energy Efficiency ◽  
Optimization Design ◽  
Control Parameter ◽  
Rapid Development ◽  
Performance Testing ◽  
Design Parameters ◽  
Leakage Flow ◽  
Blade Design ◽  
Direction Control

Abstract.With the rapid development of modern agriculture facilities, agricultural fans have been widely used due to their low pressure and large airflow characteristics. However, existing agricultural fans have large flow losses and low energy efficiencies. To increase the airflow and energy efficiency of these fans, optimization designs based on skewed and swept blades were carried out. First, a “DDZ” agricultural fan (a leaf model agricultural fan commonly used in China) was chosen as the archetype fan. Its performance curves and flow field distribution were obtained by performance testing and numerical simulation. Second, the stack lines of the skewed blade and swept blade were designed based on the original blade, 3 skewed blade parameters (skewed angle a, x direction control parameter kx, and y direction control parameter ky), and 3 swept blade design parameters (swept angle ß, z direction control parameter kz, and r direction control parameter kr). Finally, the optimal skewed blade design parameters (a = 16.8°, kx = 1.65, and ky = 0.5) and optimal swept blade design parameters (ß = 10.6°, kz = -0.33, and kr =0.6) were obtained using numerical simulations and orthogonal testing, which is a response surface method. The numerical simulation results showed that the airflow and energy efficiency ratios of the optimal skewed blade fan were increased by 4.3% and 20.5%, and those of the optimal swept blade fan were increased by 4.5% and 15.4%, respectively, in comparison with those of the original fan. The flow fields showed that the optimal skewed blade mainly reduced the radial flow at the blade root and the leakage flow. The optimal swept blade mainly reduced the leakage flow by changing the distribution of the static pressure on the blade surfaces. Keywords: Agricultural fan, Skewed-Swept blade, Numerical simulation, Optimization.

Double-section, non-retrievable casing drilling technique

2012 ◽  
Vol 52 (1) ◽  
pp. 261
Author(s):  
Keith Won ◽  
Ming Zo Tan ◽  
I Made Budi Utamain
Keyword(s):  
Planning Process ◽  
Cost Savings ◽  
Polycrystalline Diamond ◽  
Drilling Process ◽  
Drilling Performance ◽  
First Case ◽  
Drilling Technique ◽  
Drilling Technology ◽  
Improved Design ◽  
Casing Drilling

With the continuous surging in daily rental rates of oilfield exploration rigs, Casing while Drilling technology—which provides operators with an alternative drilling solution for a reduction in drilling flat-time and increased drilling operation efficiency—has appeared to be a standard part of drilling engineers’ toolkit in the well-planning process. Significant cost savings generated by Casing while Drilling have contributed to this technique being widely deployed on top-hole string installations on exploration and appraisal wells in the southeast Asia region. The double-section casing drilling technique has gained increasing popularity among operators in recent years; however, this technique development has been hamstrung by limited casing bit selections. An improved design casing bit has been highly anticipated in the industry to reduce this technique’s complexity of drilling process. Finding an equilibrium between durability and drill-out capability features for a casing bit has been a major challenge for bit designers. The increasing prospect and demand for a double-section casing drilling technique, however, has yielded the development of the casing bit design to a wider portfolio, inclusive of a more robust PDC (polycrystalline diamond compact) cutter-based drillable casing bit. The introduction of the new robust but drillable PDC cutter-based casing bit has broadened the Casing while Drilling application. The double-section casing drilling technique without the need for an additional conventional clean-out trip has become a strong contender to be part of drilling engineers’ next toolkit in delivering enhanced drilling performance and increasing operational efficiencies. This paper will introduce the first case history of the successful planning and implementation of the double-section casing drilling technique—particularly emphasising its optimised drilling performance and ease of drill-out without the need for a specialised drill-out bit.

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