Numerical simulation on downhole flow and temperature fields during drilling with nitrogen jet

In petroleum engineering, nitrogen drilling is an important technology for building wellbores between surfaces and reservoirs. To uncover the downhole flow field and the change rules of rock temperature during drilling with nitrogen jet, we constructed a CFD model by coupling the property equations of nitrogen. The flow fields of nitrogen jet and rock temperature distribution at different times were simulated. Results showed that the high speed nitrogen jet can be efficiently generated because of the nozzle acceleration and the impingement effect can be induced during drilling. The temperature of the nitrogen jet decreased due to the Joule-Thomson effect. This phenomenon suggested that the nitrogen jet induced additional thermal cracks on the bottomhole rock, which was very beneficial for the improvement of rock-breaking efficiency.

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Optical Monitoring and Numerical Simulation of Temperature Distribution at Selective Laser Melting of Ti6Al4V Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.828-829.474 ◽

2015 ◽

Vol 828-829 ◽

pp. 474-481 ◽

Cited By ~ 4

Author(s):

Ivan Zhirnov ◽

Ina Yadroitsava ◽

Igor Yadroitsev

Keyword(s):

Numerical Simulation ◽

Temperature Distribution ◽

Selective Laser Melting ◽

Ti6al4v Alloy ◽

Advanced Technology ◽

Temperature Fields ◽

Optical Monitoring ◽

Metal Powders ◽

Laser Melting ◽

Ir Camera

Selective laser melting (SLM) is a modern method for producing objects with complex shape and fine structures in one working cycle from metal powders. Combination of the advanced technology of SLM with unique properties of Ti6Al4V alloy allows creating complex 3D objects for medicine or aerospace industry. Since properties of SLM parts depend on the geometrical characteristics of tracks and their cohesion, optical monitoring is actually used to for control the process. Temperature gradient determines the microstructure and mechanical properties of the SLM part, so studies about temperature fields are primarily important. On-line monitoring during laser scanning of Ti6Al4V alloy and formation of a single track in real-time with high-speed IR camera was studied. Numerical simulation allowed estimation the temperature distribution during processing. Conclusion regarding control system based on the online monitoring of deviations of the signal from IR camera during the SLM process was done.

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Numerical Simulation and Research of Far Infrared Sterilization Tunnel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.503-504.798 ◽

2012 ◽

Vol 503-504 ◽

pp. 798-801

Author(s):

Suo Huai Zhang ◽

Ming Wei Wan

Keyword(s):

Numerical Simulation ◽

Temperature Distribution ◽

Far Infrared ◽

Measured Data ◽

Temperature Curve ◽

Experimental Temperature ◽

Cfd Model

To establish a CFD model of far infrared tunnel, get numerical simulation dates of far infrared tunnel by using Fluent soft, compared with experimental dates. The results show that the numerical simulation can attend the temperature distribution inside the tunnel, Simulated and experimental temperature curve trend of the measured data.

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Numerical Simulation of the Influence of Laser Power on the Temperature Distribution during Dissimilar Welding of Ti-Al Alloy Plates

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.826.77 ◽

2016 ◽

Vol 826 ◽

pp. 77-81

Author(s):

Eva Babalová ◽

Mária Behúlová

Keyword(s):

Numerical Simulation ◽

Temperature Distribution ◽

Laser Power ◽

Laser Beam Welding ◽

Fem Simulation ◽

Temperature Fields ◽

Dissimilar Welding ◽

Transient Temperature ◽

Al Alloy ◽

Titanium Grade

The paper deals with the design and testing of laser power for laser beam welding of titanium Grade 2 and EN AW 5754 aluminium alloy plates. Transient temperature fields during formation of dissimilar butt joints of Ti-Al alloy plates were investigated by FEM simulation using the program code ANSYS. Moving Gaussian volumetric heat source was applied to model the heat input to the weld. The influence of laser power on the temperature distribution in welded materials and parameters of the weld pool were evaluated. Based on the results of numerical simulation, the suitable laser power was suggested for the real experiments of Ti–Al dissimilar laser welding using the TruDisk 4002 disk laser.

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3D Numerical Simulation of the Airflow in a Pneumatic Splicer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.2345 ◽

2011 ◽

Vol 130-134 ◽

pp. 2345-2348

Author(s):

Xiao Xing ◽

Guo Ming Ye

Keyword(s):

Numerical Simulation ◽

High Speed ◽

Air Flow ◽

Three Dimensional ◽

Flow Characteristics ◽

Swirling Flows ◽

Computational Results ◽

Cfd Model ◽

3D Numerical Simulation ◽

Computational Fluid Dynamics Cfd

To investigate the effect of air flow in an pneumatic splicer on splicing performance, a computational fluid dynamics (CFD) model has been developed to simulate the air flow characteristics in an splicing chamber. Three-dimensional numerical simulation is conducted and standard K-ε turbulence model is used. Velocity distributions in the chamber are presented and analyzed. The computational results show that the velocities in the chamber are transonic. The air flows in the chamber are two swirling flows with opposite directions. This work also shows that CFD technique can provide a better understanding of the behavior of the high speed air flow in the air splicing chamber.

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Numerical Simulation of Thixo-co-Extrusion of 7075/AZ91D Double-Layer Tubes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.256.119 ◽

2016 ◽

Vol 256 ◽

pp. 119-125

Author(s):

Xiao Wei Li ◽

Kai Kun Wang ◽

Jin Long Fu ◽

Fei Yin

Keyword(s):

Numerical Simulation ◽

Double Layer ◽

High Speed ◽

New Technology ◽

High Strength ◽

Temperature Fields ◽

Atomic Diffusion ◽

Magnetic Pulse ◽

High Speed Trains ◽

Contact Pressures

Due to the excellent thermal conductivity and high strength of aluminum alloy and unique advantages containing shock absorbing, vibrations dampening and corrosion resistant of magnesium alloy, Al/Mg double-layer tubes have been widely utilized in household appliances, automobiles, aerospace industries, and high-speed trains in recent years. Conventionally, double-layer tubes are produced by welding, extrusion, hydroforming, magnetic pulse cladding. These processes are either complex or highly energy-consuming. To improve efficiency and reduce energy consumption, a new technology, thixo-co-extrusion (TCE), is put forward for production of double-layer tubes. In this paper, the thixo-co-extrusion of a 7075/AZ91D double-layer tube is investigated by numerical simulation. This study assesses the influences of extrusion velocity, the thickness ratios of two layers, the reheating temperatures of billets and the preheating temperature of die on the flow behaviors. The results show that the extrusion velocity and the thickness ratios significantly influence the contact pressures on the interface as well as the velocity fields. Besides, the reheating temperatures of billets and the preheating temperatures determine the distribution of temperature fields. Under the contact pressures and a certain temperature, atomic diffusion takes place on the interface between inner and outer layer, which leads to metallurgical bonding of the interface. The paper contributes to a better understanding of the thixo-co-extrusion technology for the production of double-layer tubes with desirable mechanical properties.

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Study on Optimization of Delay Method of Wedge Cut Blasting in Tunnel

Shock and Vibration ◽

10.1155/2021/1676269 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Wenle Gao ◽

Zhicheng Liu ◽

Yanping Wang ◽

Zhenwei Yan ◽

Zehua Zhang

Keyword(s):

Numerical Simulation ◽

High Speed ◽

Vibration Reduction ◽

Rock Breaking ◽

Vibration Velocity ◽

Railway Tunnel ◽

Tunnel Blasting ◽

Breaking Mechanism ◽

Coupling Algorithm ◽

Surrounding Rock Stress

Relying on the entrance section of a high-speed railway tunnel blasting project, the fluid-solid coupling algorithm based on ANSYS/LS-DYNA was used to optimize the parameters of wedge cut blasting, and the vibration could be reduced on the basis of ensuring the blasting effect. Through the combination of visual numerical simulation results and rock-breaking mechanism of wedge cut blasting, the maximum vibration velocity of different monitoring points in the model under different segmented time delay was analyzed. The results show that the best method for detonation is dividing the blastholes into three segments from upper to lower and dividing the left and right symmetrical blastholes into one segment. When the delay time is 10 ms, the average vibration reduction ratio is the best, which is reduced by 18% compared with the six-hole simultaneous blasting. In addition, the actual surrounding rock stress has a clamping effect on the cut blasting area. The wedge cut blasting footage obtained by numerical simulation was basically consistent with the field results, which proved that the model is reasonable and effective. This study intuitively and accurately demonstrated the process of cut blasting, the superposition curve of vibration velocity and the vibration reduction results under different delay times, and the effect of cut blasting. The results can be directly applied to similar projects, and the optimal blasting parameters and related issues can be solved more accurately with the help of this engineering analysis method.

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Numerical Simulation of Temperature Field in Laser Remanufacturing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.633-634.845 ◽

2014 ◽

Vol 633-634 ◽

pp. 845-849

Author(s):

Ling Dong ◽

Xi Chen Yang ◽

Yun Shan Wang ◽

Jian Bo Lei

Keyword(s):

Numerical Simulation ◽

Finite Element Method ◽

Finite Element ◽

Temperature Field ◽

Theoretical Model ◽

Temperature Distribution ◽

Simulation Method ◽

Temperature Fields ◽

Simulation Results

It plays an important role in guiding laser remanufacturing process and process control to research temperature field of laser remanufacturing. A numerical simulation method of temperature field based on MATLAB PDE Tool is proposed. Theoretical model of temperature field is presented. The temperature fields at different times are calculated and simulated with finite element method and MATLAB software with PDE Toolbox. The results show that this method can accurately calculate the temperature distribution of the laser remanufacturing process. The simulation results are helpful to optimize process parameters and to improve the quality of laser remanufacturing.

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