检索结果-内蒙古大学图书馆

A Thermal Calculation Model for Tubular Condensing Heat Exchanger

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Han, Lei Yang, Kaixuan Yang, Jiahui Li, Ruiyu Li, Yuhang Deng, Lei Che, Defu State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Xi’an710049 China Shanghai Power Equipment Research Institute Co. Ltd. Shanghai200240 China Shunde Institute of Inspection Guangdong Institute of Special Equipment Inspection and Research Foshan528300 China Xi’an Thermal Power Research Institute Co. Ltd. Xi’an710032 China

The condensing heat exchanger is commonly applied in various heat exchange systems. It can efficiently recover moisture and heat from the flue gas that contains water vapor. However, the convective-condensation heat transfer process is so complicated that no mature thermal calculation model is available. This study develops a thermal calculation model for the widely employed tubular condensing heat exchanger in industry. To characterize the degree of the heat and mass transfer, this study introduces two parameters, namely the sensible and latent heat transfer efficiencies of fin. The thermal calculations are conducted for the condensing heat exchangers reported in the literature to verify the proposed model by comparing it with the experimental data. The results show that the absolute error of the calculated sensible and latent heat transfer efficiencies is 0.0365 and 0.0268, respectively. A maximum difference of 5.2 K has been acquired between the measured and calculated values of the outlet temperature. The relative error of the condensate water flowrate is mostly within ±5.0% and ±10.0% under the bare-tube and finned-tube conditions, respectively, with a maximum deviation of 0.7 and 1.4 kg h-1. This study provides a general model for designing and optimizing various tubular condensing heat exchangers accurately. © 2023, The Authors. All rights reserved.

关键词： Mass transfer

Research on a Poly-Generation System for Gas-Biochar-Heat-Electricity by Supercritical Water Gasification of Biomass Waste

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Wang, Cui Jin, Hui School of Water and Environment Chang'an University Xi’an710054 China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of the Ministry of Education Chang'an University Xi’an710054 China Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of Ministry of Water Resources Chang’an University Xi’an710054 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi’an710049 China Ministry of Education of China Chongqing University Chongqing400044 China

Biomass energy is renewable and rich in the world, providing a solution for the shortage in fossil fuel and serious environmental pollution. Proposing efficient utilization method of biomass waste demands urgent attention. Supercritical water gasification (SCWG) process is a potential technology. In this work, a poly-generation system based on SCWG was developed to convert biomass waste to gas, biochar, heat and electricity. Firstly, mass, energy, and exergy flow were calculated at the typical condition. Subsequently, impact of various operating parameters on the hydrogen-rich syngas yield, generated electricity, thermodynamic performance was investigated. The result demonstrated that the exergy loss primarily occurred on cooler, reactor, heat exchanger and preheater, accounting for more than 90% of total exergy loss, arising from irreversible reaction, heat transfer and heat dissipation. Higher temperature, biomass concentration and preheated water exerted a positive effect for hydrogen-rich gas production and supplied heat energy, while these parameters were disadvantageous to exergy efficiency. Biochar energy was affected by biomass concentration. Energy efficiency increased with preheated water quantity and biomass concentration rising, and impact of biomass concentration was more significant. Conversely, evaluated gasification temperature displayed an adverse effect on energy efficiency. The maximal exergy efficiency reached 58.3% at 550℃, 33%, 900 kg·h-1. © 2024, The Authors. All rights reserved.

关键词： Biomass

Rapid modeling of transient processes in hydrogen-blended natural gas pipelines featuring injection and withdrawal points

学校读者我要写书评

暂无评论

International Journal of Hydrogen Energy 2025年

作者： Gong, Junhua Zhou, Chaoqun Wang, Yanxin Deng, Yajun Chen, Yujie Wang, Peng Yu, Bo Chen, Bin Yu, Zhipeng Wang, Bohong School of Mechanical Engineering Beijing Institute of Petrochemical Technology Beijing102617 China Changqing Oil and Gas Transportation Branch of Northwest Company of PipeChina Xingqing District Ningxia Yinchuan City750004 China PipeChina Engineering Technology Innovation Co.Ltd Tianjin300450 China School of Petroleum Engineering Yangtze University Wuhan430100 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China National & Local Joint Engineering Research Center of Harbor Oil & Gas Storage and Transportation Technology/Zhejiang Key Laboratory of Pollution Control for Port-Petrochemical Industry Zhejiang Ocean University Zhoushan316022 China

Blending hydrogen into natural gas pipelines enables the large-scale delivery and application of hydrogen, contributing to carbon emission reduction and promoting the transition to cleaner energy sources. Accurate and efficient predictions of transient processes in such pipelines are critical for effective management and operation. This study proposes a Fourier Neural Operator (FNO)-based model for the rapid prediction of transient processes in hydrogen-blended pipelines with injection and withdrawal points. The model is trained using numerical simulation data of pressure and flow dynamics, with initial conditions, boundary conditions, and the hydrogen blending ratio as inputs to predict hydraulic parameters along the pipeline over time. By optimizing data preprocessing and neural network hyperparameters, the model achieves high accuracy and efficiency in predicting hydraulic states. The FNO model achieves average Root Mean Squared Errors (RMSEs) of 1.06 × 10−3, 1.64 × 10−3, and 7.40 × 10−4 for pressure, flow rate, and density, respectively, with the Coefficient of Determination (R2) exceeding 0.99 for all three variables. Furthermore, the model demonstrates strong generalization capabilities, accurately predicting hydraulic states for pipeline topologies and scenarios beyond the training data. In these cases, the RMSE remains in the order of 10−3 or smaller. For a 100 km pipeline, the computational efficiency of the FNO model is at least 969 times higher than that of traditional numerical methods, with the maximum efficiency improvement reaching 5168 times as the number of pipeline cases simultaneously predicted increases. These results highlight the potential of the FNO model for real-time applications in hydrogen-blended natural gas pipeline management. © 2025 Hydrogen Energy Publications LLC

关键词： Mean square error

Research on a Poly-Generation System for Gas-Biochar-Heat-Electricity by Supercritical Water Gasification of Biomass Waste

学校读者我要写书评

暂无评论

SSRN 2024年

Biomass energy is renewable and rich in the world, providing a solution for the shortage in fossil fuel and serious environmental pollution. Proposing efficient utilization method of biomass waste demands urgent attention. Supercritical water gasification (SCWG) process is a potential technology. In this work, a poly-generation system based on SCWG was developed to convert biomass waste to gas, biochar, heat and electricity. Firstly, mass, energy, and exergy flow were calculated at the typical condition. Subsequently, impact of various operating parameters, including gasification temperature, mass flowrate of preheated water, biomass concentration, on the hydrogen-rich syngas yield, generated electricity, thermodynamic performance of the system was investigated. The result demonstrated that the exergy loss primarily occurred on cooler, reactor, heat exchanger and preheater, accounting for more than 90% of total exergy loss under different conditions, arising from irreversible reaction, heat transfer and heat dissipation. Higher temperature, higher biomass concentration and more preheated water exerted a positive effect for hydrogen-rich gas production and supplied heat energy, while these parameters were disadvantageous to exergy efficiency. Biochar energy was primarily affected by biomass concentration. Energy efficiency increased with preheated water quantity and biomass concentration rising, and impact of biomass concentration was more significant. Conversely, evaluated gasification temperature displayed an adverse effect on energy efficiency. The maximal exergy efficiency reached about 58.3% at 550°C, biomass concentration of 33%, preheated water mass flowrate of 900 kg·h-1 © 2024, The Authors. All rights reserved.

关键词： Biomass

Research on the Performance Enhancement of Accident Tolerant Fuel for Eliminating Core Melting Based on Isaa

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Tang, Shaowei Zhang, Bin Shan, Jianqiang School of Nuclear Science and Technology Xi’an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China

Based on the Integrated Severe Accident Analysis (ISAA) code, this paper studies the influence of thermo-physical properties of Accident Tolerant Fuel (ATF) materials on the plant responses to severe accidents. By selecting ATF with IMDP as the core material and SiC as the cladding material and changing different physical parameters, it is found that fuel density and cladding density have the greatest influence on the fuel temperature rise. In addition, to eliminate core melting, the ATF parameters in ISAA are modified step by step to improve the thermodynamic properties of the fuel, and the core is finally made to reach thermal equilibrium. According to the calculation results, the supporting capacity of the cladding, the supporting capacity of the core supporting plate, and the melting point of the fuel are the main factors limiting the core melting, which can be eliminated by appropriately improving these properties. © 2022, The Authors. All rights reserved.

关键词： Thermodynamic properties

Dynamic Analysis and Optimization of Heat Transfer Performance During Electrospray Cooling with Ethanol-R141b Mixture

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Tian, Jiameng Kong, Lingwen Li, Bufa Wang, Junfeng Chen, Bin Xiong, Junhui School of Energy and Power Engineering Jiangsu University Zhenjiang212013 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Zhejiang Ningbo315201 China

Electrospray (ES) cooling that relies on Coulomb forces for energy-efficient liquid atomization is promising to meet the requirement of high-heat-flux thermal dissipation for micro-sized electronics under relative low... 详细信息

关键词： Ethanol

An Experimental Study on the Hypergolic Process Enhanced by Pre-Ignition Heat Release: [Amim][Dca]/Furfuryl Alcohol Blends Reacting with White Fuming Nitric Acid

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Wu, Yingtao Wang, Zhi Fei, Lihan Guo, Yang Liu, Yang Tang, Chenglong Huang, Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China Research Center of Energetic Material Genome Science Institute of Chemical Materials China Academy of Engineering Physics Mianyang China

The hypergolic ignition behaviors of [AMIM][DCA] (1-allyl-3-methylimidazolium dicyanamide)/furfuryl alcohol (FA) blends reacting with white fuming nitric acid (WFNA) are investigated using drop test approach. Morphology results from two high speed cameras and temperature profiles from an infrared camera are combined in analyzing the hypergolic process. A typical hypergolic process observed in this work involves a mixing dominant stage, a stage with moderate temperature rising and vapor/secondary droplets emerging, and a stage with violent temperature rising accompanied by flame occurrence. Two kinds of delay times are used to characterize the hypergolic process which are found to be nonmonotonic with the variations of FA fractions. FA, though not hypergolic with WFNA, exhibits extensive pre-ignition heat release due to its physical and chemical properties, which enhances the hypergolic process of [AMIM][DCA]/FA blends with WFNA. © 2022, The Authors. All rights reserved.

关键词： Ionic liquids

Study on the effect of particle flow state on the stability of LIBS carbon content detection signal 7

学校读者我要写书评

暂无评论

Study on the effect of particle flow state on the stability ...

7th International Conference on power engineering, ICOPE 2019

作者： Pan, Yuqing Hu, Zhengtao Xu, Heng Zhou, Qulan Li, Na Deguchi, Yoshihiro State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Graduate School of Engineering Science Osaka University Japan

Rice husk, a type of biomass fuel, is rich in amorphous silica. Laser-induced breakdown spectroscopy (LIBS) is a fast-responding non-contact detection method which can realize on-line detection of rice ash components. This paper aims to explore the optimum working conditions of LIBS and extend the compatibility of LIBS technology. The paper uses the sample motion state simulation system to simulate ash, so that the particles can be laser-induced breakdown during the vertical drop and horizontal motion, and then the effect of particle flow state on the stability of the LIBS detection signal can be determined. In addition, the paper compares the effects of two laser pulse widths on the stability of LIBS detection signal by using a 1 ns pulse width laser and a 6 ns pulse width laser to improve the detection error. Experimental studies have found that long pulse width laser provides better stability of spectrum, and the relative standard deviation (RSD) of the detection result is smaller than that of short pulse width laser, and the RSD is smaller in the state of horizontally transferring samples, which can obtain the spectral signal with stronger line intensity. Moreover, sample in conveyor, by contrast, leads to more stable signals. © ICOPE 2019 - 7th International Conference on power engineering, Proceedings. All rights reserved.

关键词： Stability

Surface display of CadR protein on Rhodopseudomonas palustris CGA009 for enhanced heavy metal bioremediation

学校读者我要写书评

暂无评论

Journal of Hazardous Materials 2025年 494卷 138592页

作者： Wang, Minmin Gao, Zixuan Jiang, Qiushi Mu, Xuefang Jiang, Youmin Li, Yanjing Zhang, Sihu Cao, Wen Guo, Liejin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xianning West Road Xi'an710049 China

Heavy metal pollution poses significant ecological and public health risks, and surface display engineering shows promise for bioremediation in this area. Although anoxygenic photosynthetic purple nonsulfur bacteria (PNSB) have been effectively applied to degrade pollutants due to their metabolic versatility, the use of surface display technology in PNSB remains very limited. In this study, we constructed a surface display system using Rhodopseudomonas palustris CGA009 as the host. The metal-binding protein CadR was fused with outer membrane protein A (OmpA) and expressed in CGA009. SDS-PAGE and immunofluorescence analysis identified the successful expression of the fusion protein on the cell surface. In addition, we used flow cytometry to explore the enhancement effects of linker peptides and different promoters on surface display efficiency under different light intensities. The surface display system enhanced the heavy metal resistance of the host bacteria, and the maximum removal rate of Cd2 + reached 95.6 %. By means of Langmuir isotherm analysis, the maximum biosorption capacity of the system for Cd2+ is 101.11 mg/g. The system demonstrates feasibility for application in complex real-world environmental samples. The presence of various metal ions does not interfere with the system's specific adsorption of Cd²⁺. It can stably maintain an adsorption efficiency of over 80 % under conditions of pH 6–8, temperatures of 20–35°C, and light intensity of 1000–6000 lux. Additionally, the system achieves a removal efficiency of 94.3 % in Cd wastewater. In summary, this study provides a reference for the development of photosynthetic bacterial surface display systems and provides an advanced bioremediation strategy for heavy metal contaminated wastewater. © 2025 Elsevier B.V.

关键词： Bioremediation