bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Roadside Buildings Roof Shapes and Tree Plantings on the Vehicle Exhaust Gas Pollution Dispersion in the Urban Street
Authors: Hsu Frances , Bennett Ajanae 
Published: March 2023

Abstract
In this study, the effects of roadside building roof shapes and roadside tree plantings on the dispersion of vehicle exhaust gas pollution in the urban street have been carefully explored. Three typical roof shapes, i.e., flat, triangle and round shapes, are considered in the present work. Firstly, the numerical simulations of air pollution transport in the atmospheric turbulent boundary layer with/without the vegetation canopy have been performed using Computational Fluid Dynamics (CFD). Secondly, the mean flow patterns and the distribution of turbulent kinetic energy (TKE) are then examined. Finally, the concentrations of the air pollution have been carefully explored. It is found that the triangle roof could result in a lower concentration of air pollution in the street canyon. The existence of the roadside trees could decrease the air pollution concentration, although its influence is much weaker than the roof shape. It is also found that the concentration of air pollution is quite related to the flow pattern and TKE distribution. This study could provide helpful guidance on the urban planners on the design of the urban street in the future.
Numerical study of different micro-channel structures on fluid flow and heat transfer performance
Authors: Chen Zijian 
Published: March 2023

Abstract
This research mainly proposed three new types of micro-channel heat sink structures. Numerical simulations and simulation calculations were carried out on the heat sink structure. The three groups of inlet flow rates were used as the main variables to analyse the three new types of heat sinks, model flow characteristics and heat transfer performance. In addition, it was compared with the traditional rectangular micro-channel heat sink (RT-MCHS). Based on and compared with RT-MCHS, three new microchannel heat sinks, reverse concave microchannel heat sink (RC-MCHS), co-directional concave microchannel heat sink (CC-MCHS) and convex reverse concave microchannel heat sink (CRC-MCHS), were designed and studied numerically. The comparative analysis of MCHS design performance includes fluid flow characteristics, fluid heat transfer performance and heat transfer efficiency. The effects of inlet velocity on the Darcy friction coefficient, pressure drop, Nusselt number, average outlet temperatures and efficiency factors were studied numerically as inlet velocity from 1 m·s-1 to 5 m·s-1. The results show that the optimal strategy in the new design is the CRC-MCHS, which can hinder the flow of fluid and enable sufficient heat exchange between the liquid and the substrate. In addition, at the optimal inlet flow rate of 3 m·s-1, the outlet water temperature of CC-MCHS is the lowest, indicating the heat transfer performance of the electronic components is the best.
Numerical simulation of two-phase evaporation and condensation
Authors: Chang Wei , Zhang Fangju , Fang Kun , Tan Gongli , Fan Pengjie 
Published: March 2023

Abstract
The evaporation and condensation mechanism of two-phase flow is studied. The Euler-Euler pattern is used to express the evaporation and condensation properties of two-phase flow. The research shows that the tracking program can accurately track the interface. The thermal resistance on the confluence of the condensation part and insulation part becomes larger. The working fluids have significant influence of two-phase.
Approximation properties of some Bernstein-Schurer type operators
Authors: Lian Boyong 
Published: March 2023

Abstract
This paper mainly studies the approximation properties of Bernstein-Schurer operators based on a non-negative real parameter λ. By analysis techniques and the method to make the kernel estimation, the author studies the convergence order of this Schurer operators for the function class θBV[0,1 + p]. Our conclusion expands the research results of Çetin.
Differences among IllustrisTNG series and a Brief Comparison with the Illustris Project
Authors: Dai Zhengyu , Dong Jinao , Liao Runyu , Yue Qiwei 
Published: March 2023

Abstract
The IllustrisTNG project is one of the most advanced cosmological gravity and magnetohydrodynamical models that simulates the formation and evolution of galaxies. It focuses on figuring out the physical processes involved based on the moving-mesh code AREPO. This project consists of three series (TNG50, TNG100, TNG300) with different box sizes, resolution, and physical parameters while each series also contains sub-simulations with lower resolution (TNG50-2, TNG50-3, TNG100-2, TNG100-3, TNG300-2, TNG300-3). The purpose of this paper is to illuminate the major differences and connections among different series of the IllustrisTNG project by analysing the data and carrying out corresponding visualization. Moreover, since the IllustrisTNG project is built upon the previous Illustris project, the improvements of the new model have been compared to the former one. Based on the analysis, different IllustrisTNG series differ in physical and numerical parameters, research areas, quantity of sample and so on. In the meantime, there are a lot of connections especially among the sub-simulations and we draw several figures, which provide a clear insight. The situation between the new model and the old one is very similar while the former introduces new methods and includes new physics which make the simulation process much more accurate. These results help to understand the ongoing problems and offer a guideline to enable the establishment of a future simulation model.
Application of CVOFLS method in multi vortex shear flow field
Authors: Cui Liying , Yang Yingge , Ren Cuiping 
Published: March 2023

Abstract
Coupled Volume of Fluid and Level Set method inherits the advantages of VOF and Level Set methods, takes VOF function as the main body to simulate the fluid motion interface, and corrects the normal direction of the interface through Level Set function, so as to effectively overcome the shortcomings of the two methods. The numerical simulation example of multi vortex shear flow field shows that this method can ensure better simulation accuracy of moving interface and higher calculation efficiency.
A Numerical Investigation of Tidal Disruption Rate Enhancement in Post-Starburst galaxies
Authors: Xue Marco Tinyeung , Xie Fuguo 
Published: March 2023

Abstract
Tidal disruption is an uncommon but important phenomenon that occurs when a star’s gravity is overcome by that of the SMBH which it is orbiting. In this process, researchers may gleam various properties of the host galaxy’s nucleic region, such as the accretion process, debris fallback, behavior of active galactic nuclei and quasars, etc. In this work we present a numerical analysis of TDE rates using the loss cone theory, a leading theoretical picture in this field, based on changes to several pivotal variables, such as SMBH mass, stellar mass, velocity dispersion etc. We then extend this to fit the profiles of E+A post starburst galaxies and the occasion of binary black hole systems.
Method of using theodolite’s observation data of fixed star to evaluate INS’s attitude accuracy based on time-delay compensation
Authors: Kong Xianglong , Liu Chenghao , Wu Xingcun , Liu Kecheng , Liang Junhao 
Published: March 2023

Abstract
In order to evaluate the attitude accuracy of the TT&C’s SINS under dynamic condition, a new method of using theodolite’s observation data of fixed star to evaluate SINS’s attitude accuracy based on time-delay compensation is proposed. The detailed design is given, and the influence of the time delay is analyzed based on real data experiments. The data analysis and experimental results shows that the new method can improve the computation accuracy, and it is valuable for engineering application of evaluating SINS’s attitude accuracy under dynamic conditions.
Prediction on the axial water thrust characteristics of pump turbine runner under partial load
Authors: Guo Jianqiang , Bi Huili , Luo Guohu , Wang Zhengwei 
Published: March 2023

Abstract
For the high head pump turbine, the unit instability during its operation mainly dues to the hydraulic vibration inside the machinery, which will cause the mechanical fatigue failure under certain circumstances. In this paper, the flow pattern and the runner axial water thrust in turbine model under partial load were analyzed by numerical simulation. The internal flow field instability and vortex load characteristics of the runner were analyzed to obtain the reasons for the different axial water thrust characteristics of the runner under two different loads. The results showed that due to the reduction of the guide vane opening, the flow rate is smaller at 50% load, and the free flow vortex structure on the high-pressure side of the runner blade inlet strengthens the impact of the water flow on the runner. Moreover, when the pressure difference between the runner blades decreases and the axial water thrust of the blades decreases, the total axial water thrust of the runner decreases and fluctuates frequently with time.
Numerical simulation of steam flooding in offshore heavy oil reservoir after water flooding
Authors: Zhang Qingquan , Sun Xiaofei 
Published: March 2023

Abstract
Steam flooding is an effective method to enhance oil recovery in heavy oil reservoirs. However, the influence factors of steam flooding will affect the development of heavy oil reservoir after the traditional water flooding. So the dynamic prediction of steam flooding needs to be performed before the development scheme is implemented. In this study, the 3D reservoir model was established by the reservoir numerical simulation software CMG; Combined with operating parameters of oilfield, the influence of steam temperature, steam injection timing and steam quality on the development effect of L7 block in offshore heavy oil reservoir was studied by using 3D reservoir model. The results show that compared with traditional water flooding, steam flooding has better development effect, and the cumulative oil production can reach 100.673 × 104m3; With the increase of steam temperature and steam quality, the cumulative oil production, incremental oil production and heat efficiency have an increasing trend; This result also suggests that the development method of higher steam temperature and steam quality conforms to the principle of economic development; For steam injection timing, the earlier the steam injection is more conducive to better development results.
Coupled double-distribution-function lattice Boltzmann model with streaming-collision process
Authors: He Zhuojie , Liang Ruifang 
Published: March 2023

Abstract
A coupled double distribution function lattice Boltzmann model with streaming-collision process is presented. In this model, continuity and momentum equations are recovered by a density distribution function and energy equation is recovered by a total energy distribution function, and the specific-heat ratio and Prandtl number are flexible. At the same time, the streaming-collision process is used as update rule. Couette flow is simulated as a numerical test. The numerical results agreed relatively excellent with the analytical solutions.
Dynamic Load Analysis of an Centrifugal Pump Axle using FSI Simulation
Authors: Cai Biaohua , Zhang Zheng , Chen Yinzhong , Tang Zhou 
Published: March 2023

Abstract
The mechanical characteristics of the impeller are important indicators that determine the working characteristics of the pump. The pump is subjected to periodic hydraulic loads during the working process. This load will cause the dynamic deformation of the impeller and the impeller shaft, thereby further affecting the distribution of the fluid. Liquid-solid coupling is used. Method, the rated operating point of centrifugal pump is analyzed, and it is proved that the dynamic stress of the impeller and the impeller shaft meets the requirements, which lays a foundation for the formulation of the control strategy of the impeller.
Layout of measuring points for flue gas flow velocity in coal-fired power plants based on CFD technology
Authors: Wu Junhao , Liu Chunling 
Published: March 2023

Abstract
In view of the existence of 90° bends in the flue after desulfurization in coal-fired power plants and the complicated distribution of flue gas flow velocity, the CFD simulation technology is proposed to simulate and analyze the flow characteristics of the flue flow field, and to find suitable flow velocity measurement points. On this basis, a set of on-line monitoring system for flue gas flow velocity and pollutants is designed by using LabVIEW.
Numerical simulation of gas-liquid interface in high-pressure water-blowing chamber
Authors: Tang Xionghui , Liu Yiou 
Published: March 2023

Abstract
The load on the water chamber increases with the pressure level and blowing rate of the system, and the demand for theoretical and experimental studies related to the quantitative parameters of water chamber blowing safety becomes more and more frequent. In this paper, CFD computational fluid dynamics method is used to carry out the dynamics modeling and simulation of three-dimensional non-constant gas-liquid two-phase internal flow field of the test water chamber and the actual water chamber blowdown process to obtain the dynamic distribution of flow parameters in the water chamber under different working conditions. The results found that to ensure the safety of the water tank, as long as to ensure that the high-pressure air into the water tank at the end of the first two stages, the “bubble” movement process always does not interfere with the bulkhead, you can ensure that the high-pressure air in the water tank in the free expansion and gravity floating state, the water tank pressure will be only slightly higher than “gas - water cross-section” of the static pressure, at this moment the water chamber safety.
Thermal fluid lubrication analysis of hydrodynamic journal bearing based on mass conservation boundary conditions
Authors: Hu Xinliang , Yu Kaiping , Zhang Junxiong 
Published: March 2023

Abstract
The thermal-hydrodynamic lubrication analysis of bearing with different bearing speed and eccentricity was carried out under Reynolds boundary conditions and mass conservation boundary conditions, and the variation of performance parameters such as oil film carrying capacity with speed and eccentricity were analyzed in detail for the calculated results, and the calculation results under the two different boundary conditions were compared and analyzed. The results show that the boundary conditions have a greater influence on the lubrication flow calculation results, the Reynolds boundary conditions have a faster calculation process, and the mass conservation boundary conditions are recommended when focusing on the analysis of lubrication flow.
Comparative analysis of radiant and radiator heating system for a residential building
Authors: Aacharya Ananta , Koirala Robin , Khanal Shuvas , Baral Bivek 
Published: March 2023

Abstract
Energy use for heating and cooling at the household level is rising annually. The residential sector consumes about 69% of energy consumption, out of which the highest percentage is shared by traditional fuel for cooking applications, followed by heating and cooling applications. In such a scenario, the primary goal should be to meet future heating and cooling energy demand through the use of novel technologies such as radiant heating systems (RHS). By utilizing low-temperature fluid flowing through the pipe, the RHS is more efficient than a standard heating system in maintaining the correct interior temperature. These systems are not frequently implemented in Nepal. It is crucial to compare the applicability of the system with technologies like radiator systems. The building provided by Urban Development and Building Construction (UDMC) is used for the study. The radiant and radiator heating system is designed, and the effects of different parameters on the heat transfer coefficient are studied. The maximum heating load is 50kWh for mid of January. A radiant heating system with a panel area of 18.24m2 is sufficient to satisfy the heating demand, while radiator heating requires a panel area of 3.6m2. To meet the same load, the total pipe length for the radiant and radiator heating systems is 300m and 42m, respectively. Radiant and radiator heating systems had a heat transfer coefficient of 7.76W/m2 and 15.34W/m2, respectively. The variation is because the radiator system must provide the same amount of heat to the building while having a smaller surface area than the radiant heating system.
Numerical study of a coil pump and comparison with field measurement
Authors: Pandey A , Bijukchhe P L , Khanal P , Acharya S , Chitrakar S , Neopane H P 
Published: March 2023

Abstract
Rural irrigation could be challenging in regions without proper access to electricity. In many remote places of Nepal, where the irrigation takes place in the vicinity of a river stream, a river water pump or coil pump can be used to supply water from the lower river terrain to the field. Water powered coil pump is a reciprocating pump that operates by rotating a coiled tube, by harnessing the power of a flowing river. A comparison in performance of cylindrical and conical shaped coil pumps was done both experimentally as well as numerically in this work. Under the river velocity of 0.9m/s, the maximum discharge at zero lift condition for the conical pump was 11,500 liters/day while for the cylindrical pump it was 8,600 liters/day. However, the conical pump could not generate lift more than 6.5m while the cylindrical pump performed well even at 11m head. The Numerical study was also carried out in order to visualize the flow patterns and compare the performance of the pumps while varying different parameters. The 3D computation domain of the pump for four cases (two cases varying the number of turns and two cases with change in shape) were generated and numerically studied using OpenFOAM. The interaction, being a multiphase case, interFoam solver was used, and to simplify the simulation laminar turbulence model was taken. The pressure and water volume at the outlet in the simulation were measured and compared between different cases. It was observed that the pressure obtained while using a cylindrical pump was 2.52 % more than that while using the conical pump. The outlet pressure was found to be increasing by 35% while increasing the number of turns from 7 to 15 in cylindrical and 42.5% in case of conical coil pump. The volume flow rate was observed to be more frequent in the case of the conical pump. Due to constraints of computational conditions, the experimental setup could not be totally replicated. However, the outcome showed a similar trend as obtained in the experiment. It was found that the cylindrical pump was better for the higher head, whereas the conical pump had shown better results for higher discharge.
Assessing the performance of a demonstrative hydrogen fuel cell power train in the chassis of an internal combustion engine vehicle
Authors: Shrestha Y. , Subedi A. , Sapkota M. , Paudel P. , Yadav N. K. , Thapa B. S. 
Published: March 2023

Abstract
In the present day in the global context, approximately 2 billion internal combustion engines (ICEs) are estimated to be in use. Nearly 7.3 billion metric tons of carbon dioxide (CO2) were released into the atmosphere as per the survey on the transportation sector in 2020, making up 41% of all emissions. To solve pollution challenges related to ICEs, recent advancements of alternatives to ICEs have pushed the globe to establish clean energy sources such as hydrogen fuel cells. The conversion of an ICE vehicle to a fuel cell vehicle is able to add further support to its development besides the 30% emission reduction since the old ICE vehicle would not be discarded. FCEVs are seen as a true replacement between BEVs and ICEs since more energy can be stored in less space as compared to BEVs. The objective of this paper is to analyse the energy consumption of a fuel cell-driven motor in the internal combustion engine vehicle chassis of Maruti 800, through mathematical modelling, then compare the specifications with that of an ICE-driven system. The analysis provides details on the optimization of drive system components to maximise the fuel cell energy consumption efficiency based on fuel cell power source requirements for a range of velocities and road gradients. The modifiable specifications of drive system components in the mathematical model ensure reproducibility for any drive cycles and system scenarios.
Machine learning to predict the antimicrobial activity of cold atmospheric plasma-activated liquids
Authors: Özdemir Mehmet Akif , Özdemir Gizem Dilara , Gül Merve , Güren Onan , Ercan Utku Kürşat 
Published: March 2023

Abstract
Plasma is defined as the fourth state of matter, and non-thermal plasma can be produced at atmospheric pressure under a high electrical field. The strong and broad-spectrum antimicrobial effect of plasma-activated liquids (PALs) is now well known. The antimicrobial effects of PALs depend on many different variables, which complicates the comparison of different studies and determining the most dominant parameters for the antimicrobial effect. The proven applicability of machine learning (ML) in the medical field is encouraging for its application in the field of plasma medicine as well. Thus, ML applications on PALs could present a new perspective to better understand the influences of various parameters on their antimicrobial effects. In this paper, comparative supervised ML models are presented by using previously obtained data to predict the in vitro antimicrobial activity of PALs. A comprehensive literature search was performed, and 12 distinct features related to PAL-microorganism interactions were collected from 33 relevant articles to automatically predict the antimicrobial activity of PALs. After the required normalization, feature encoding, and resampling steps, two supervised ML methods, namely classification and regression, are applied to the data to obtain microbial inactivation (MI) predictions. For classification, MI is labeled in four categories, and for regression, MI is used as a continuous variable. Sixteen different classifiers and 14 regressors are implemented to predict the MI value. Two different robust cross-validation strategies are conducted for classification and regression models to evaluate the proposed method: repeated stratified k-fold cross-validation and k-fold cross-validation, respectively. We also investigate the effect of different features on models. The results demonstrated that the hyperparameter-optimized Random Forest Classifier (oRFC) and Random Forest Regressor (oRFR) provided superior performance compared to other models for classification and regression. Finally, the best test accuracy of 82.68% for oRFC and R
2 of 0.75 for the oRFR are obtained. Furthermore, the determined most important features of predictive models are in line with the outcomes of PALs reported in the literature. An ML framework can accurately predict the antimicrobial activity of PALs without the need for any experimental studies. To the best of our knowledge, this is the first study that investigates the antimicrobial efficacy of PALs with ML. Furthermore, ML techniques could contribute to a better understanding of plasma parameters that have a dominant role in the desired antimicrobial effect. Moreover, such findings may contribute to the definition of a plasma dose in the future.