bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on identifying parameter of DFIG-based wind farm based on mathematical mechanization analysis
Authors: Wang Liguo , Liu Hanyu , Chen Jianhua , Yu Chunlai , Wang Zongjie 
Published: February 2022

Abstract
In order to obtain precise running parameters which are the intrinsic cause resulting in sub-synchronous resonance (SSR) in transmission line with series compensation capacitor, an approach that can be used to identify the dynamic equivalent parameters of DFIG (doubly-fed induction generator) -based wind farm has been proposed based on the mechanized mathematics theory. Core work is to derive the analytical expressions of the stator resistance, inductance and the rotor resistance, inductance and the mutual inductance which are expressed by the sampling voltage, current and active power based on polynomial modelling and characteristic set of the mathematical mechanization. Simulation results which are associates with the actual sampled data of a wind farm show that, the equivalent parameters consist of 32 DFIGs have been given and verified by proposed approach. Also, the maximum identifying error of corresponding resistance and inductance of the stator and rotor was lower than 5% based on sampling an actual DFIG farm. This work can provide a reference for analysing and suppressing SSR which is a bottleneck for a wind farm stable running.
A multistage optimal placement approach of monitors considering voltage sag and fault position observability
Authors: Liu Haiyong , Dai Baihua , Zhu Hongfang 
Published: February 2022

Abstract
Reasonable placement of limited monitors is beneficial to reduce the cost of monitoring for voltage sags assessment. However, existing methods only consider the observability of voltage sags, leading to information loss. To capture all the voltage sags and the corresponding fault positions in distribution network, a multistage optimal placement approach of power quality monitors considering voltage sag and fault position observability is proposed. The initial requirement of voltage sag monitoring, that is, voltage sag observability is ensured by monitoring reach area method. Then, based on a simple fault location method, the fault location observability index is proposed for describing monitoring effects for fault position observability. A series of placement schemes with different costs and monitoring effects are given, which is convenient for engineers to choose the proper placement scheme according to the budget and demand. The simulation results carried on the IEEE 69-bus system show that the proposed approach can is correct and available.
Current situation analysis of electrohydrogen production under the background of “Carbon Neutralization”
Authors: Tang Wei , Tan Qingkun , Cai Ranran 
Published: February 2022

Abstract
As an energy carrier to promote the large-scale development and utilization of renewable energy, hydrogen energy is one of the means to drive China’s economic development and energy restructuring, and to implement the “double carbon” goal. First, the development status of hydrogen energy at home and abroad has been sorted out, and the development paths of typical countries have been summarized briefly, the development trend of electric hydrogen production technology is studied and some suggestions are put forward to promote the further development of electric hydrogen production. The conclusion of this paper can provide reference for the hydrogen industry and the Energy Supply and energy use industry to implement the goal path of “carbon neutral”.
Numerical study of blowdown period of double-end break loss of coolant accident in PWR based on RELAP5
Authors: He Xiaoqiang , Gao Puzhen , Zhao Hai 
Published: February 2022

Abstract
Loss of coolant accident (LOCA) is one of the most severe accidents of nuclear power plants (NPP). During the early blowdown period, the system is in a high-pressure gradient and high-velocity gradient state. Therefore, the hydrodynamic forces and safety analysis are highly related to calculating thermal-hydraulic parameters in the flow field. This paper studied the factors and modeling methods that affect the calculation of thermal-hydraulic characteristics under large break LOCA conditions. Firstly, the reactor core and primary system of a typical two-loop pressurized water reactor (PWR) NPP is modeled using the system analysis code RELAP5 Mod4.0. The normal operation state is obtained after the steady calculation. Then, transient calculation of double-end break LOCA is implemented considering the effects of break opening time and the pressurizer. The influence of the results on the calculation of hydrodynamic force has also been analyzed. Finally, the modeling method of reactor pressurized vessel (RPV) downcomer is presented. It is found that the flow field can be better simulated when the downcomer is modeled with parallel channels and several transverse junctions. Thus, this paper provides meaningful suggestions for modeling and simulation in the early blowdown period under LOCA conditions and contributes to further hydrodynamic load calculation and reactor safety analysis.
Review on new heavy oil viscosity reduction technologies
Authors: Li Xuening , Zhang Fusheng , Liu Guoliang 
Published: February 2022

Abstract
Lots of gum and asphaltene in heavy oil caused high viscosity, high density and poor fluidity, which makes it very difficult to exploit and transport heavy oil. This paper introduces the mechanism and application of five new viscosity reduction technologies, including microbial viscosity reduction technology, biosurfactant viscosity reduction technology, ultrasonic viscosity reduction technology, magnetic treatment viscosity reduction technology and supercritical carbon dioxide viscosity reduction technology. At present, single viscosity reduction technology is difficult to solve the problem of heavy oil production and transportation. So the development direction of heavy oil viscosity reduction technology is the composite use of various technologies. In the future, it is necessary to develop new viscosity reduction technologies suitable for heavy oil production and transportation from the perspective of studying the structure and performance of heavy oil.
Shielding performance test of irradiation monitor tube transport container
Authors: Zhuang Dajie , Lian Yiren , Chen Lei , Wang Zhipeng , Wang Pengyi , Sun Shutang , Sun Hongchao , Li Guoqiang , Liu Hongyan 
Published: February 2022

Abstract
This paper focuses on the transport container of irradiation monitoring tube about test technology of the γ radiation shielding performance. Through simulation calculation and test measurement, the external radiation level of irradiation monitor tube transport container is obtained. The experimental results are compared with the calculated results, and the position deviation of the radioactive source in the container is analysed. The results show that it is feasible to use the radioactive source with small activity to test the shielding performance, and improve the shielding performance detection technology of long cylindrical transport container.
Emergency evaluation model for nuclear criticality accidents of uranium enrichment facility
Authors: Jia Linsheng , Yang Yapeng , Wang Renze , Feng Zongyang , Wang Ning , Liang Boning 
Published: February 2022

Abstract
Accident emergency evaluation technology is an important part of emergency preparedness and response for nuclear critical accidents. Moreover, emergency management also requires that facility with potential nuclear criticality accidents should have the emergency evaluation capability of the accident, so it can provide auxiliary decision support for early emergency decision-making. The paper introduces the emergency evaluation model for nuclear criticality accident of uranium enrichment facilities, including criticality fission number estimation, released source term estimation and dose estimation. The potential nuclear critical accident scenario of uranium enrichment facilities considered in the paper is uranyl fluoride solution criticality. Solution criticality is a complex accident scenario that may involve multiple criticality problems. In the paper, the criticality fission number is estimated based on the critical radiation monitoring data, which can give the results quickly and meet the emergency requirements. Estimation of criticality fission number is a technical difficulty, which can directly reflect nuclear criticality accident scale and provide a theoretical basis for conservative protective actions.
Experimental study on the foam performance and fire extinguishing performance of aqueous foam stabilized by alkyl polyglucoside and urea
Authors: Li Fan , Yu Xiaoyang , Zong Ruowen 
Published: February 2022

Abstract
Foam extinguishing agents are the most effective extinguishing agents for liquid fires. The search of relevant domestic and foreign commercial foam fire extinguishing agent patents found that most commercial foam fire extinguishing agent formulations contain urea. In order to understand the mechanism of urea’s influence and clarify the application parameters of urea-added aqueous foam in the fire extinguishing process, this research investigated the surface tension, foaming ability, foam stability, and fire extinguishing performance for alkyl polyglucoside and alkyl polyglucoside/urea foams. It is found that the addition of urea promotes the formation of surfactant micelles, resulting in a decrease in critical micelle concentration, while the surface tension and foaming ability of the alkyl polyglucoside solution are only moderately affected by the urea. Besides, urea significantly improves the fire extinguishing performance of alkyl polyglucoside foam and the influence of urea concentration on fire extinguishing time is remarkable. On the one hand, the enhanced extinguishing performance can be explained by the increase of foam stability. On the other hand, urea produces incombustible gases such as NH3 and CO2 under the action of the high temperature of the fire, which may improve the fire extinguishing performance by cooling effect and asphyxiation effect. The increase in expansion ratio and the foam flow rate are beneficial to shorten the extinguishing time. The research results can guide the design of foam extinguishing agents.
Safety analysis of hydrogen explosion accident in high level waste tank
Authors: Chen Lei , Sun Shutang , Wang Zhipeng , Wang Pengyi , Zhuang Dajie 
Published: February 2022

Abstract
A large amount of radioactive waste liquid is generated in the spent fuel reprocessing process, and high-level waste is stored in a high-level waste tank. During storage, a hydrogen explosion accident may occur, resulting in the leakage of radioactive materials. This article reviewed the basic situation of high-level waste liquid and high-level waste storage system. The safety analysis of the hydrogen explosion accident was conducted, from the source and generation mechanism of hydrogen, the accumulation process of hydrogen in the tank, the possible ignition source and the possibility of explosion in the tank, the pressure generated by the hydrogen explosion, and the probability of tank failure due to hydrogen explosion are discussed. Suggestions were made on the design, operation, and safety analysis of high-level waste tanks in China, which provided a reference for the safe development of high-level waste storage facilities in commercial reprocessing plants.
Study on NOx emission from an improved wood stove
Authors: Li Wenjun , Zheng Quanjun , Wang Xiaodong , Zhao Jie , Liu Changrui , Lv Haiyang , Dong Changqing , Hu Xiaoying 
Published: February 2022

Abstract
Aiming at the problem that the NOx emission of civilian biomass wood stoves is difficult to meet the ultra-low emission requirements and the widespread use of biomass fuels, on the basis of traditional wood stoves, the stove structure is improved and a biomass pyrolysis device is added to make the stove have a reducing atmosphere. The final NOx emission mass concentration is reduced to below 150 mg/m3, which meets the emission standards for civilian wood stoves.
Synthesis of amino-functionalized silicon fiber cloth composite for effective removal of Cu (II) from wastewater
Authors: Zhang Yaoyao , Wei Zhengwen , Zhang Guiying , Wang Wei 
Published: February 2022

Abstract
In this paper, amino modified silica fiber cloth (KSF) was prepared by the chemical grafting method. The SEM, FTIR and TGA techniques were employed for the characterization of the silica fiber cloth (SF) and KSF. FTIR analysis suggests that functional amino groups of γ-aminopropyl triethoxysilane (KH550) were grafted on the surface of KSF. The influence of single factor on adsorption performance was studied. The results showed that the adsorption capacity of KSF can reach 178.46 mg-g1, the experimental adsorption data were fitted closely by pseudo-second-order kinetic model, adsorption isotherms were simulated well by Langmuir model. Thermodynamic analysis revealed that the adsorption process was endothermic, entropy-driven and spontaneous. The adsorption-desorption experiments demonstrated that KSF showed no significant removal efficiency loss even after ten consecutive cycles, indicating the good stability of prepared KSF material. Our findings suggested the KSF can serve as potential candidates for the practical application of wastewater containing heavy metals.
Synthesis of nanoporous acicular-mullite ceramic and electroless platinum coating for particulate matter entrapment and catalytic combustion
Authors: Wan Yanlei , Xu Chengjian , Zhou Qiuhong , Chen Hao , Xu Qi 
Published: February 2022

Abstract
Crystal-structured acicular-mullite ceramic with high porosity and interpenetrated networks was fabricated for diesel particulate filter (DPF), followed by electroless deposition of platinum (Pt) catalysis throughout ceramic surfaces from an aqueous Pt (IV) solution. The integrated material was characterized and compared with commercial cordierite particulate matter (PM) filter, exhibiting many excellent properties in surface area, porous ratio, and loading capacity for both soot and catalyst. The resulting surface density of Pt nanoparticles attained as high as 8.0 × 109/cm2 due to the 3-dimensional architecture, while maintaining a pore ratio, 63.72%, relative to 52.60% in its counterpart. Deposited Pt nanoparticles artfully serve as catalysis for combustion of carbon soot, potentially implemented for diesel engine filter, reducing the particulate matter emission for environmental protection. The catalytic performance was evaluated by a regular thermal gravity analysis (TGA) measurement, showing that the significant drop of soot conversion temperature, and soot convert rate could be further improved by co-precipitating CeO2 catalyst additive. This material, thereby, could readily adapt itself into large-scale production.
Scenario analysis of the re-electrification of Yunnan’s industrial sector facing the peak of carbon in 2030
Authors: Li Qiushuo , Cheng Beibei , Zhu Xianwen , Li Kangyan , Xie Yanjun , Wang Peng , Shu Jie 
Published: February 2022

Abstract
Energy conservation and emission reduction in the industrial sector is the focus of urban energy conservation and emission reduction, and it is also the sector with the greatest emission reduction potential and the longest time-consuming. Based on the analysis of the current situation of the terminal energy consumption and carbon dioxide emissions of Yunnan’s industrial sector from 2010 to 2019, the scenario analysis method is used to predict the energy consumption and carbon emission reduction potential of Yunnan’s industrial sector from 2021 to 2035.
Research on complaint prediction based on feature weighted Naive Bayes
Authors: Zheng Jian , Yang Wei , Wang Changchun , Jiang Dandan , Wang Dan , Yang Qi , Zhang Yijiao 
Published: February 2022

Abstract
Complaint prediction is a hot topic in current research. Due to complaint prediction is random, the accuracy of complaint prediction is not high. To solve this problem, this paper proposes a complaint prediction method based on feature weighted Naive Bayes. According to rough set theory, we first calculate the importance of each conditional attribute, combine the importance of attribute as the weight with the naive Bayes classifier to form a weighted naive Bayes classifier. We use multiple classifiers to make predictions, the latter classifier performs iterative learning on the basis of the previous classifier, and finally all classifiers are given different weights to make decisions. The experimental results show that the proposed method effectively combines the weighting method and the Naive Bayes method to achieve reliable prediction of complaints.
An accurate RANS-based transition prediction approach (part II)
Authors: Russo S , Natale N , Citro V , Giannetti F 
Published: February 2022

Abstract
We present a CFD analysis of a wind tunnel model of the new laminar turbo-prop aircraft designed in the frame of the European Clean Sky 2 programme. The work presents the numerical results of the aerodynamic performance of a scaled model of the innovative laminar turboprop A/C wing by using a CFD approach that includes the transition prediction. Numerical results will be compared by considering two different procedures: a) CFD analyses in which the transition location is imposed and b) CFD analyses in which the position of the transition is evaluated. The prediction of the transition location and the laminar flow extension is based on a numerical framework based on the coupling between a high-fidelity RANS tool and a Linear Stability (LNS) solver. According to this method, boundary layer equations are written in the conical formulation and the solution of RANS equations and transition onset is obtained through an eN method based on the LNS calculations.
Spectral project - application of FAST-OAD code to the conceptual design of a hydrogen fuelled commercial aircraft
Authors: Oak Mayur , Fabre Alice , Delavenne Martin , Van Eric Nguyen , Benard Emmanuel , Defoort Sébastien 
Published: February 2022

Abstract
With the increase in the air traffic, reducing the aviation environmental impact is the key challenge of the community. This has called for more research in the area of using alternative fuels which will reduce the greenhouse gas emissions and which can provide similar or better environmental performance. This work presents a preliminary design methodology of a mid-range single aisle commercial aircraft using Hydrogen as fuel which is stored in an integrated tank in the fuselage. The iterative design process was achieved by using overall aircraft design approach through the FAST-OAD open-source software.
This study describes the models used for a first approximation of structural and insulation weight of liquid Hydrogen (LH2) tank and fuel boil off computations. It then presents the impacts of an LH2 storage system on the overall aircraft design with an emphasis on the centre of gravity (CG) travel and the additional fuselage length necessary to accommodate the LH2 tank. An additional parametric study has also been carried out to understand the effect of some design parameters on overall design. Finally, an environmental study has been conducted to evaluate the direct emissions of this aircraft in operation. The only emissions that result from the combustion of hydrogen are nitrogen oxides (NOx) which were evaluated using the Boeing Fuel Flow Method (BFFM2) and water vapor (H2O) which was evaluated based on the fuel burned. As a result of this study significant reduction in NOx and CO2 emissions as compared to existing design are envisaged, thus showing the promising potential of Hydrogen fuelled aircraft.
Design of Supersonic and Hybrid engine based Advanced Rocket (SHAR)
Authors: Relangi Naresh , Peri Lakshmi Narayana Phaneendra , Levi Domingos Caio Henrique Franco , Fossella Amalia , Leite Henriques Julia Meria , Ingenito Antonella 
Published: February 2022

Abstract
The paper deals with the design of a two-stage to orbit rocket launcher loaded with a solid rocket booster, scramjet, and hybrid rocket for delivering a 100kg payload in 200 km circular orbit. The possibility of implementing a cavity-based axisymmetric circular combustor in a scramjet is proposed. Computational analysis on various injector locations in a circular combustor and their validation with the test bench results were performed. The utilisation of a hybrid rocket in the final stage of the launcher to deliver the payload is discussed and the performance characteristics of the circular scramjet combustor and the hybrid rocket are shown. The overall mission proposed based on the sustainable and reusable characteristics.
Model-based dynamic performance simulation of a microturbine
Authors: Erario Mario Leonardo , De Giorgi Maria Grazia , Przysowa Radoslaw 
Published: February 2022

Abstract
Microturbines can be used not only in models and education but also to propel UAVs. However, their wider adoption is limited by their relatively low efficiency and durability. Validated simulation models are required to monitor their performance, improve their lifetime, and design engine control systems. The aim of this study is to develop a numerical model of a micro gas turbine for engine performance predictions and prognostics. To build a reliable zero-dimensional model, the available compressor and turbine maps were scaled to available test bench data with the least-squares method, to meet the performance of the engine achieved during bench and flight tests. A steady-state aeroengine model was then developed and compared with experimental operating points. Selected flight data were then used as input for the transient engine model. The EGT temperature and the fuel flow were chosen as the two key parameters to validate the model, comparing the numerical predicted values with the correspondent experimental ones. The observed difference between the model and flight data was lower than 3% for both EGT and fuel flow.
Numerical analysis of cyclorotor aerodynamic properties in hovering state
Authors: Cogan Shawn , Gagnon Louis 
Published: February 2022

Abstract
Cyclorotors employ cyclically pitched axial rotor blades to create an extremely maneuverable propulsion system. The pitch angle throughout one rotation is defined so that the resulting blade angle of attack follows a prescribed function that generates lift. The lift and drag produced is also affected by curvilinear flow, dynamic stall, and induced velocities, all of which affect the resulting angle of attack. These factors form complex relationships that are difficult to model analytically, making it hard to predict a cyclorotor’s performance. Here, a numerical model is presented which can be used to predict thrust and power draw of different cyclorotor configurations. Parameters include airfoil, number of rotor blades, rotational velocity, pivot function, fluid properties and Reynold’s number. The numerical model builds on previously implemented approximations but focuses on time-efficient calculations so that many configurations may be calculated in an iterative process. In each iteration the parameters can be adjusted according to machine learning or other metaheuristic optimization algorithms to determine an optimal configuration.