bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical simulation of the shock-wave structure of a reacting hydrogen-air mixture in a model channel
Authors: Kukshinov N V , Mamyshev D L 
Published: November 2021

Abstract
The paper deals with the results of numerical simulation of hydrogen-air combustion in a supersonic flow of a model channel of a known configuration, investigated in the “HyShot” project. The simulation is carried out by solving the Favre-averaged system of Navier-Stokes equations, supplemented by a turbulence and combustion model and a chemical-kinetic mechanism. The influence of different throat heights on the performance of the model due to combustion efficiency and total pressure loss coefficients is investigated.
Results of numerical simulation on a thick teardrop airfoil at low Reynolds numbers
Authors: Akimov M A , Polivanov P A 
Published: November 2021

Abstract
A symmetrical thick teardrop airfoil was investigated in this work. A numerical simulation was performed with a laminar flow, using the Implicit Large Eddy Simulation method. The fields of flow parameters in the vicinity of the airfoil were obtained for Reynolds numbers 3.5e+4 and 6.9 e+4.
Thermodynamic properties of propane and methane hydrates doped with sodium hydroxide
Authors: Gets K V , Zhdanov R K , Bozhko Yu Yu , Belosludov V R 
Published: November 2021

Abstract
Pure and sodium hydroxide doped with single-component hydrates of methane and propane are studied using molecular and lattice dynamics methods. Vibration density of states and the dependence of Helmholtz free energy on temperature and cell volume are calculated. Dynamic stability of empty and filled by gas sI and sII structures doped with 1 or 2 NaOH molecule is shown in the wide range of temperature values. Comparison of free energy values allows calculating the thermal expansion coefficient and demonstrating the possibility of self-preservation effect in NaOH-doped methane and propane hydrates with ~1.8 and ~1.4 mol% of sodium hydroxide, respectively.
Assessing the effect of proppant compressibility on the conductivity of heterogeneously propped hydraulic fracture
Authors: Skopintsev A M 
Published: November 2021

Abstract
Hydraulic fracturing is a technology that is widely used in the development of oil and gas formations. Given that the fracture closure has a strong impact on production, quantifying the resulting fracture conductivity is critical for optimizing treatment design. The goal of this paper is to better understand the influence of the closing stress on the fracture conductivity when the proppant distribution is heterogeneous. In addition to the spatial proppant distribution, the conductivity of the propped fracture is affected by proppant deformation and embedment. Numerical results indicate that compressibility of proppant can significantly change the residual fracture aperture and, consequently, production performance in oil and gas reservoirs
Simulation of a laminar-turbulent flow in three-dimensional aerodynamic configurations
Authors: Poplavskaya T V , Boiko A V , Demyanko K V , Kirilovskiy S V , Nechepurenko Y M 
Published: November 2021

Abstract
The goal of the paper is to determine the position of the laminar-turbulent transition in the boundary layer of a prolate spheroid using the eN-method with the calibration of threshold N-factors. It is demonstrated that the predicted and experimental data on the laminarturbulent transition are in good agreement.
Quality estimation of the nozzle spray by measuring the brightness of the reflected light
Authors: Batalov V G , Stepanov R A , Vasilev A U 
Published: November 2021

Abstract
This paper presents the results of the laboratory and numerical experiments performed to measure the sizes of transparent liquid droplets sprayed in air. The results of the laboratory experiments were mainly obtained using the Glare Point Technique (GPT) which gave information about the droplet size and the brightness of the light reflected by drops. The relationship between the brightness of the light reflected from the surface of droplets and their sizes was analyzed. Theoretically, the brightness of light scattered by a single spherical drop is proportional to the drop surface area and, accordingly, to the square of the drop diameter. It has been observed experimentally and verified numerically that the theoretical dependence obtained is relevant only for the brightest droplets because of nonuniform illumination. The results of the numerical experiments with a random sample of drops indicated the dependence of the total brightness of reflected light on the effective droplet size. It is shown that, for a fixed total volume, the total brightness of light reflected by drops is proportional to the droplet Sauter mean diameter.
Software package for testing three-dimensional shape measurement methods using structured lighting
Authors: Dvoynishnikov S V , Zuev V O , Kabardin I K , Kulikov D V , Rahmanov V V 
Published: November 2021

Abstract
This work aims at creating a universal software package for the development and testing of triangulation methods using structured lighting for measuring the three-dimensional geometry of objects in difficult ambient lighting conditions. As a result, a software package meeting the stated requirements is created. Lighting is based on the Fong model. A method for preloading objects is implemented to optimize the operation of the software package. An accelerated method for creating shadow maps is proposed and implemented. The developed software package is shown to successfully perform all required functions.
Problems of an experimental study of a reverse flow in the turbulent channel flow
Authors: Zaripov D I 
Published: November 2021

Abstract
The problems of experimental study of the near-wall reverse flow (NWRF) phenomenon observed in a turbulent channel flow are discussed. Until now, the problem of detecting the NWRF events has been associated with the lack of spatial resolution of measurement methods. The present study, using the example of high-speed PIV measurements, shows that problems associated with the influence of the measurement error arise even when a high spatial resolution is achieved.
Estimating the uncertainty of measurements of thermal conductivity of thin films of thermoelectrics with the 3-omega method
Authors: Makarova E S , Novotelnova A V 
Published: November 2021

Abstract
Using the method of computer simulation, the uncertainty of measurements of the thermal conductivity of silicon, which is often used as substrates, and also thin films based on bismuth, is estimated. The influence of the application of an additional dielectric layer between the thermoelectric film and the resistive heater on the measurement results is shown.
Thermal expansion of nickel-chromium ChS88U alloy at high temperatures
Authors: Kozlovskii Yu M , Stankus S V 
Published: November 2021

Abstract
The experimental results of the study of thermal expansion of nickel-chrome alloy in the temperature range of 293.15–1400 K are presented. The phase transformation of the first kind in the alloy is observed. The estimated error of the obtained data is 3%. Approximation equations and a table of reference values for the temperature dependence of the studied properties are obtained.
Equation of state for rhodium at high pressures
Authors: Khishchenko K V 
Published: November 2021

Abstract
An equation of state has been developed for rhodium in a wide range of changes in the specific volume and internal energy. The results of calculations of the thermodynamic characteristics of this metal are presented in comparison with the available experimental data at high pressures. This equation of state can be used in the numerical simulation of hydrodynamic processes under intense impulse influences on matter.
The study of the effect of forced air supply on the combustion of liquid fuel dispersed by superheated steam
Authors: Mukhina M A , Kopyev E P , Anufriev I S 
Published: November 2021

Abstract
In the present work, the effect of forced air supply on the combustion process of liquid hydrocarbons was studied using diesel fuel as an example. The content of intermediate components of the flame and the temperature distribution along the flame symmetry axis were studied using an atmospheric burner with liquid fuel atomizing by a steam jet. The gas composition of equilibrium combustion products and the heat release were investigated. The influence of the excess air ratio in the combustion chamber of the burner device on the thermal and environmental characteristics was shown.
Studies various factors effecting the synthesis of submicron silicon dioxide particles by leaching from waste dumps of the Balaklavskoe deposit
Authors: Turyanskiy V A , Baranov G A , Chayka T V , Gavrish V M 
Published: November 2021

Abstract
The paper presents the results of studies of the main parameters of synthesis of silicon dioxide powder from Balaklava deposit sludge with silicon dioxide content of 24%. During the study caustic soda solution is used as a leaching agent and sulfuric acid was used as a precipitant. At the leaching stage the concentration of leaching agent, the ratio of liquid phase to solid phase, the optimum temperature of leaching as well as the mode of pulp agitation are investigated. At the precipitation stage, the following parameters are considered: concentration of precipitating agent and temperature of the precipitation process. As a result of using the optimal parameters the high efficiency of obtaining silica powder of 98.56% is achieved. Average particle size is 200-800 nm, and agglomerate size is more than 800 nm.
Wafer Direct Technology for Mini LED Flip Attachment
Authors: Hiraki Kazuo 
Published: November 2021

Abstract
We would like to introduce the mechanism structure of our wafer direct die attachment technology for mini LED. Wafer direct technology is structured from two parts of that one is adhesive one shot dipping and other is pinhole free chip shooting. 1st, we developed “One shot wafer dipping” which can transfer the adhesive to around 30,000 chips of mini LED on a wafer at once. Second section is to take about die mounting. Common die bonder use an ejector pin to pick up mini LED chip. Ejector pin makes a pinhole on wafer and lead air into between wafer and mini LED chip. This air is effective to remove mini LED chip from wafer by the pick up nozzle. Ejector pin of die bonder leaves a broken piece of wafer on chip. We developed wafer direct chip shooting technology. Wafer direct chip shooter also use an ejector pin for shooting down mini LED chip. But wafer direct does not make any pinhole on wafer that means no broken piece of wafer exists. Our wafer direct technology maximize productivity of mini LED die bonding and minimize faulty ratio of mini LED die bonding.
Influence of Different Surface Passivation on Photoelectric Properties PbS QDs
Authors: Yang Yingxiang , Pu Hongbin , Bei Xu , Chen Chunlan , Wang Min , Hu Xiamiao 
Published: November 2021

Abstract
The photoelectric characteristic of ITO/PbS quantum dots (QDs)/Al structure based single and hybrid iodine ions(I−) passivated PbS QDs have been investigated. The ITO/PbS QDs/Al structure with hybrid I− passivation have demonstrated a high light dark ratio of 565.5 at -2V. It is the result of removing more organic ligands on the surface of PbS QDs and introducing larger amount of I−. This work demonstrates that the hybrid I− passivated process has great potential in the performance improvement of PbS QDs based photovoltaic device.
Research on CarMaker and Cloud Computing Platform Co-Simulation Based on APO
Authors: Ren Nver , Jiang Rong , Zhang Dongze 
Published: November 2021

Abstract
An cloud computing platform based on B/S architecture and docker container technology for autonomous driving simulation has been established in this paper. The map editor module of the cloud platform lets users design 3D scenes for simulating and testing automated driving systems. When the customized roadway scene for simulation created, it would be saved as OpenDrive format both for the server of cloud platform and CarMaker’s TestRun which all parameters of the virtual environment (vehicle, road, tires, etc.) are sufficiently defined. Then, based on the application online (APO) communication protocol of CarMaker, the local APO agent service was created. When the 27 parameters of vehicle dynamics received from CarMaker server, they were sent to the cloud platform in real time through UPD protocol. The process of data communication is completed by APO agent. Through the work above, a co-simulation between cloud platform and CarMaker could be successfully established for autonomous driving with seventeen-degree-of-freedom. Through the co-simulation experiment, it is found that the real-time data sampling frequency of the co-simulation is 70Hz, which completes the synchronous simulation of carmaker and cloud platform.
Topology Optimization and Design for Additive Manufactured Supporting Structure of Vehicle Rudder
Authors: Chen Jingyi , Xin Kehao , Gu Xiaolong , Ji Hongjuan 
Published: November 2021

Abstract
The object investigated in this work is a design method for the supporting structure of vehicle rudders, which are the crucial components in flight control system. As a practical application of topology optimization for additive manufacture, the design process was presented in this article. To obtain the optimal material distribution, topology optimization based on SIMP method was applied, with compliance minimization as the optimization objective. A numerical optimization model was built and calculated in Inspire, and the result in an equivalent load scheme of 30 percent point load and 70 percent uniform pressure was adopted to be the initial geometry for the subsequent design. Concentrating on realizing the optimized geometry, this design took a series of technical constrains for additive manufacture and mass requirements into consideration. Notably, the FEM simulation for the supporting structure is necessary, which consist of stress analysis and mode analysis. And the technical feasibility was verified in its practical manufacturing process. Finally, by the experiment about dynamic characteristic, it is verified that the lightweight rudder designed in this work can satisfy all the requirements for flight control.
Fracturing Parameters Optimizing Simulation of Horizontal Well In WeiYuan Shale Gasfield
Authors: Che Mingguang , Wang Meng , Zeng Bo , Song Yi , Jiang Wei , Zhang Xiaofeng , Dong Kai 
Published: November 2021

Abstract
Multistage fracturing and multi-clusters with long lateral fracturing were applied during developing the WeiYuan shale gas field, and the fracturing parameters were variable obviously for the fracturing lateral, perforating clusters, pumping rate, fracturing fluid volume and proppant quality. In this paper, the 3D geological model of a WeiYuan shale gas pad was used to simulate and optimize the fracturing parameters of the shale gas horizontal wells. The simulating results show that there is a reasonable matching relationship between different fracturing lateral length and the perforating clusters, and there is an optimal fluid volume and proppant quality. As the length of the fracturing lateral and the number of clusters increase, the spacing of horizontal wells need to be reduced reasonably. With the purpose of fracturing parameters optimization for WeiYuan shale gas horizontal wells, it is recommended to increase the number of perforation clusters, increase the treating rate, and use the reasonable fluid volume and proppant quality for different fracturing lateral. The research results of this paper have guiding significance for the optimization and treatment of fracturing shale gas horizontal well.
Modelling igneous rock mechanics parameter based on logging data in Shunbei oil field
Authors: Li Wenxia , Song Weiqiang , Liu Jingtao , Chen Xiuping , Mu Huidong 
Published: November 2021

Abstract
In order to improve the rate of penetration (ROP) in Permian igneous rock strata, the rock mechanics is modeled based on the continuous logging data (acoustic, density, caliper, resistivity and gamma logging) and confirmatory indoor experiments. The model considers the influence of well collapse and expansion on logging data in igneous rock formation to improve the calculation accuracy. Based on this model, the continuous profile of Permian compressive strength, tensile strength, mud content, internal friction angle are calculated, and then the differences of Permian strata in the north, middle and south of the oilfield are further compared and analyzed. The results can provide support for the optimization of efficient rock breaking and reservoir fracturing technology.
Design of solar light tracking system Research on energy autonomy system design of outdoor patrol car based on solar energy
Authors: Wang Wen-Lan , Bai Xiong-Huai 
Published: November 2021

Abstract
The Inner Mongolia has abundant solar energy and electricity resources. Because of the long distance between cities, transmission lines are too long, making it difficult to check lines. In order to solve the problems existing in the inspection work, this paper studies a kind of outdoor inspection vehicle using solar energy, the energy system of the inspection vehicle can independently complete the charge and discharge, so as to realize the inspection task. This paper focuses on the energy autonomy of the on-site inspection vehicle for solar energy. According to the design requirements of the inspection vehicle, appropriate parts are selected to build an energy autonomy inspection system for the inspection vehicle. Then the solar tracking algorithm and maximum power tracking control algorithm are used to improve the conversion rate of solar panels and achieve fast charging. Finally, the hardware and software of the solar controller are designed, and the corresponding functions are debugged.
Application of Micro-resistivity Scanning Imaging Logging Data in Reservoir Thickness Division
Authors: Wang Xinnan 
Published: November 2021

Abstract
Reservoir parameter interpretation is one of the main contents of reservoir description, which affects the whole process of oilfield development. According to the characteristics of micro-resistivity scanning imaging logging, which can directly reflect the changes of lithology and physical properties of reservoirs, this paper compares the thickness and interbed division of reservoirs with conventional logging data, this paper finds out the shortcomings of the conventional logging data in the interpretation of thickness and the division of interlayers, and combines the core analysis data to examine the differences in the correlation on the coring wells, and obtains good results, it has laid the foundation for the establishment of new interpretation procedure.
Research Progress on Calculation and Control of Unaccounted for Gas of Natural Gas Pipeline Network
Authors: Chen Huiyu , Li Shanshan , Zuo Lili , Li Wanjun 
Published: November 2021

Abstract
At present, volume measurement is still used in transfer measurement of natural gas in China, so the calculation and management of Unaccounted for Gas are based on volume measurement. With the change of natural gas measurement method from volume measurement to energy measurement, the calculation and management of Unaccounted for Gas based on energy measurement will be paid more and more attention. This paper investigates the calculation methods and management measures of Unaccounted for Gas based on volume measurement in China and Unaccounted for Gas based on energy measurement in other countries, and compares the research progress. The results show that: the general principles of Unaccounted for Gas calculation in China and other countries are basically the same, but the calculation formulas are not completely the same. All countries consider the input gas, output gas, line pack variation and self-consumption gas. On this basis, Italy considers the known leakage, and Britain considers the known leakage and the daily calorific value shrinkage caused by its settlement rules. In order to reduce Unaccounted for Gas, the UK regularly verifies meter, carries out the research on Unaccounted for Gas baseline, and actively participates in the global Unaccounted for Gas benchmarking. Australia replaces the old main line and reduces the operation pressure of pipeline, which significantly reduces Unaccounted for Gas. The calculation methods and control measures of Unaccounted for Gas based on energy measurement in Italy, Britain and Australia can be used for reference in China.
Study on Renewable Energy Accommodation Capacity Assessment Method Based on Time Series Production Simulation
Authors: Su Yinsheng , Ma Qian , Zhang Qiang , Yuan Quan , Huang Xinlei 
Published: November 2021

Abstract
In order to solve the problem of low accommodation rate of renewable energy in a single region, considering the output characteristics of wind power and photovoltaic, grid constraints and cross regional power exchange, an optimization model of renewable energy accommodation capacity in a cross regional power grid year is established. This paper analyzes the factors restricting the accommodation capacity of renewable energy, and determines the access scale of renewable energy units according to the characteristics of different power grid scale, load and power supply structure. And then taking the annual maximum accommodation capacity of renewable energy as the goal, the time series production simulation model is established, considering the constraints such as regional load balancing, power transmission and output of the network cable, unit output, unit optimization power ramp rate and renewable energy output. To improve the renewable energy accommodation capacity, the three factors of power system interconnection level, power regulation performance and load characteristics can be considered.
Transient Response Analysis of Multi-layer Sloshing Fluid in LNG Tank
Authors: Song Liye , Deng Jiajia , Lu Jinshu , Wang Bin , Xue Dawen 
Published: November 2021

Abstract
The stratified LNG is the potential cause of rollover, so the analysis of the interface behavior is very important. In this work, a three-layer dynamic simulation model of BOG, LNG, and liquid nitrogen of sloshing stratified LNG in a tank was built. The transient behaviors of the layers were simulated, and the effects of factors such as the period of sloshing (T = 0.2, 0.4, 0.6, 0.8 and 1.0 s) and the amplitude of sloshing (A=0.01~0.06 rad) were analyzed. It was found that instability of the interface was aggravated over time. There was a specific period of sloshing in which the layers of fluid were relatively stable, away from this period the fluid layer became less stable. The influence of sloshing amplitude on the behavior of the interface presented a wave characteristic. The simulation results of the coupling with different sloshing periods and sloshing amplitude showed that the interface behavior of stratified sloshing was the most severe when the sloshing period was 0.2 s and the sloshing amplitude was 0.05 rad.
Study on turbulent flow in <1-2> wave wall tube heat exchanger
Authors: Zhang Liang , Zhang Anlong 
Published: November 2021

Abstract
The traditional straight wall tube heat exchanger has low heat exchange efficiency, in order to solve this problem, the turbulent flow in wave wall tube heat exchanger was studied by numerical simulation. It is found that the unique corrugated structure of the heat exchange tube in the wave wall tube heat exchanger can improve the flow state of the fluid in the heat exchanger. The average pressure drop of heat exchanger gradually increases with the increase of Reynolds number Re. Under the same conditions, the average pressure drop of wave wall tube heat exchanger is lower than that of straight wall tube heat exchanger. The improvement of heat exchange performance of heat exchanger can not be realized only by increasing the inlet flow of heat exchanger. The wave wall tube heat exchanger can strengthen the heat exchange of the fluid in the heat exchanger.