检索结果-内蒙古大学图书馆

Development of a two-phase flow solver with two-fluid model based on OpenFOAM: Validation against two-phase boiling flow

引用

Annals of Nuclear Energy 2025年 220卷

作者： Wu, Wenqiang Huang, Tao Du, Peng Feng, Zhenyu Zhang, Dalin Zhou, Lei Song, Gongle Deng, Jian Qiu, Zhifang Tian, Wenxi Qiu, Suizheng Su, Guanghui State Key Laboratory of Multiphase Flow in Power Engineering Shaanxi Key Laboratory of Advanced Nuclear Energy and Technology School of Nuclear Science and Technology Xi'an Jiaotong University Shaanxi Xi'an710049 China Nuclear Power Institute of China 328 Changshun Avenue Chengdu610213 China

The continuous advancement in computer technology and mathematical-physical models has significantly propelled the development of numerical reactor technology. There is a growing focus on high-fidelity, multi-scale, and multi-physics coupling within a unified framework. OpenFOAM, based on the finite volume method, has emerged as a promising tool for addressing this challenge. This study explores its capabilities in system-level scales, successfully developing a two-fluid, six-equation solver. The realistic closure models cover flow and heat transfer scenarios within vertical channels under pre-CHF conditions. A virtual thermal structure accounts for conjugate heat transfer between the fluid and the solid. Furthermore, the solver adheres to the discretization and solution principles within the OpenFOAM framework. The developed solver has been extensively validated against experimental data for two-phase boiling flow, with results showing good agreement, thereby demonstrating the solver's success. This work builds upon previous efforts involving the drift-flux solver and indicates that OpenFOAM can effectively handle one-dimensional or system-level scale calculations. It provides robust support for future endeavors in multi-scale and multi-physics coupling technologies. © 2025 Elsevier Ltd

关键词： Finite volume method

来源：评论

学校读者我要写书评

暂无评论

Uncertainty and Sensitivity Analysis of Containment Aerosol Removal Under Severe Accident

SSRN

引用

SSRN 2025年

作者： Ou, Pingwen Chen, Yongzheng Chen, Peng Ouyang, Yong Guo, Chao Su, Guanghui China Nuclear Power Technology Research Institute Co. Ltd. Shenzhen518000 China State Key Laboratory of Nuclear Power Safety Technology and Equipment China Nuclear Power Technology Research Institute Co. Ltd. Shenzhen518000 China School of Nuclear Science and Technology Xi'an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory of Multiphase Flow in Power Engineering China

This study focuses on the uncertainty and sensitivity analysis of containment aerosol removal under severe accident conditions using the severe accident integral code ASTEC, validated by experiments carried by CNPRI, and the coupled uncertainty and sensitivity tool SUNSET. A "separated" methodology is introduced, which distinguishes between thermal-hydraulic and aerosol boundary conditions to highlight the impact of containment aerosol mechanisms. Eleven uncertainty input parameters related are selected for uncertainty propagation and the Spearman correlation coefficient is utilized to describe sensitivity. The removal factor exhibits significant variation, with peaks due to temporary enhancement of diffusiophoresis deposition caused by corium relocation and subsequent steam generation. Uncertainty in the removal factor is substantial before aerosol release termination and narrows afterward. The gravitational settling and the diffusiophoresis deposition are the most important contributors with approximately 70% and 20% deposited aerosol mass, respectively. The initial mass medium diameter, the gravitational shape factor and the agglomeration shape factor are the most influential input parameters in aerosol removal, including in-containment deposition and environmental release, and they should be considered discreetly with conservatism in source term estimation and radioactive consequence evaluation in nuclear engineering. © 2025, The Authors. All rights reserved.

关键词： Sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

Quantitative detection of alkali metal Na based on laser-induced breakdown spectroscopy technology

引用

Meitan Xuebao/Journal of the China Coal Society 2025年第4期50卷 2262-2270页

作者： Shen, Sijie Li, Chi Zhou, Wangzheng Wang, Zhenzhen Yan, Junjie Hou, Zongyu Wang, Zhe Deguchi, Yoshihiro School of Energy and Power Engineering Xi'an Jiaotong University Xi'an710049 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China State Key Laboratory of Power System Operation and Control Tsinghua University Beijing100084 China Institute for Carbon Neutrality Tsinghua University Beijing100084 China Department of Energy and Power Engineering Tsinghua University Beijing100084 China Shanxi Research Institute for Clean Energy Tsinghua University Taiyuan030032 China Graduate School of Technology Industrial and Social Sciences Tokushima University Tokushima770-8506 Japan

The alkali metal compounds released from high alkali fuels such as low-quality coal during thermal utilization can affect the normal operation of thermal equipment. Therefore, rapid online detection of alkali metal content in low-quality coal is of great significance for controlling alkali metal release during combustion. The alkali metal Na element is used as the detection object, and the mixed samples of graphite and sodium chloride powder with different ratios are used as experimental samples. The influencing factors of measuring Na element in samples using laser induced breakdown spectroscopy (LIBS) technology are studied. The impact of two signal strength calculation methods on signal stability is compared. The influence of experimental parameters on signal strength and signal-to-noise ratio is analyzed. The quantitative calculation models for Na element have been established. Research has shown that the characteristic spectral lines of Na element, Na I 588.995 nm and Na I 589.592 nm, are suitable as the main analytical spectral lines. Using the area intensity of the dual line characteristic spectral lines of Na element as the signal intensity can effectively improve signal stability. When the laser energy is 60 mJ and the delay time is 1 000 ns, the relative standard deviation of spectral signal intensity is low and the signal-to-noise ratio is high. The quantitative calculation models are established using traditional calibration method, partial least squares (PLS) method, and support vector machine (SVR) with spectral signal intensity as the input and Na element addition in the sample as the output. The accuracy of each model is compared and analyzed. The results indicate that the PLS model may exhibit overfitting when the sample size is small and the input quantity is large. The fitting accuracy of the SVR model is 0.978 3, the root mean square percentage error of the training set is 13.42%, and the root mean square percentage error of the test set is 13.51

关键词： Sodium chloride

来源：评论

学校读者我要写书评

暂无评论

Teardrop-like micro pin fin coated nanotube arrays chip for enhancement of flow boiling electronics cooling

引用

International Journal of Thermal Sciences 2025年 214卷

作者： Chen, Hongqiang Gao, Quan Ma, Xiang Li, Kai Du, Wangfang Li, Caifeng Zhang, Yonghai Wei, Jinjia School of Chemical Engineering and Technology Xi'an Jiaotong University 28 Xianning West Road Shaanxi Xi'an710049 China Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing100190 China School of Engineering Science University of Chinese Academy of Sciences Beijing100149 China Xi'an Shaangu Power Co. Ltd. Xi'an710075 China

Phase change flow boiling heat transfer in microchannel is a very efficient thermal management mode for high-power electronics/devices cooling. However, achieving comprehensive enhancement of flow boiling heat transfer performance at low power consumption is still challenging. Herein, we devised and manufactured a teardrop-like micro-pin-fin coated stable copper hydroxide nanotubes array chip surfaces (S-Nanotube), demonstrating their exceptional enhancement in flow boiling heat transfer efficiency. A series of experiments were conducted using HFE-7100 as a working fluid within a semi-open microchannel. Compared to the smooth surface, the critical heat flux (CHF) and the maximum boiling heat transfer coefficient (HTC) of the S-Nanotube is increased by 82.1 % (from 45.1 to 72.9 and then to 82.1 W/cm2) and 140.5 % (from 5955 to 11,325 and then to 14,316 W/m2·K) at extremely low-pressure drop (≤4 kPa), showing a high coefficient of performance (COP). The temperature of the onset of nucleate boiling on the S-Nanotube surface is reduced by 26.4 %, and the heat flux is greatly increased in a small wall temperature variations (ΔT ≤ 10 °C). In situ observation and analysis of the surface properties and the bubble dynamics, the S-Nanotube chip promotes the phase change heat transfer process by providing massive nucleation sites, reducing bubbles size and residence time, and enhancing the wicking wetting capacity. These findings provide guidance for the rational design of boiling heat transfer-enhanced surfaces and heat sinks and point the way to achieving efficient thermal management of power devices. © 2025 Elsevier Masson SAS

关键词： Electronic cooling

来源：评论

学校读者我要写书评

暂无评论

Thermodynamics analyses on a novel CHP system integrated with multi-grade thermal energy storage

引用

Journal of Energy Storage 2025年 106卷

作者： Liu, Rongtang Zhang, Kezhen Qin, Yuanzhi Wan, Kaidi Xu, Can Liu, Ming Ningbo Institute of Technology Beihang University Ningbo315800 China Xi'an Thermal Power Research Institute Co. Ltd. Xi'an710054 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Dongfang Boiler Co. Ltd. of Dongfang Electric Group Chengdu611731 China

The high penetration level of intermittent renewable power necessitates the crucial requirement for combined heat and power systems to possess both high efficiency and flexibility. However, the heat-controlled operation modes of traditional combined heat and power systems impose limitations on their efficiency and flexibility. Therefore, it is of great significance to develop a heat-power decoupling technology that exhibits exceptional efficiency and flexibility. A novel combined heat and power system integrated with multi-grade thermal energy storage is proposed in this study. Thermodynamic analysis models of all operational conditions are developed, and the comprehensive characteristics of efficiency and operational flexibility for the proposed system are assessed by taking a 330 MW system as an example. Results show that the proposed system can decrease/increase 16.05 MW/30.96 MW power loads comparing with the reference system during the charging/discharging periods under the design condition. Energy efficiency of the proposed system can reach 49.40 %, which is improved by 1.66 percentage points. Exergy analysis reveals the exergy destruction order for the proposed system, and shows that the combustion and heat transfer in the boiler are the major process of exergy dissipation. Moreover, operation strategies of the proposed system during charging-discharging cycle are explored and formulated under off-design condition, suggesting that thermodynamic performances of the novel system under various conditions even extreme conditions exhibits exceptional properties. The maximum heat load of the proposed system can be improved by 46.78 % comparing with the reference system, and the maximum improvement of power load capacity during charging-discharging cycle is 14.58 percentage points. This study provides a promising approach for multi-grade thermal energy storage to improve the comprehensive characteristics of combined heat and power systems. © 2024

关键词： Charge storage

来源：评论

学校读者我要写书评

暂无评论

Efficient conversion of CO2 to CH4 through supercritical water gasification of plastic with calcium looping

引用

Renewable Energy 2025年 249卷

作者： Li, Xuantong Wu, Hongtu Wang, Weizuo Wang, Junying Wu, Chunfei Jin, Hui State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi Xi'an710049 China School of Chemistry and Chemical Engineering Queen's University Belfast BelfastBT9 6FS United Kingdom

Calcium looping (CaL) is a promising technology with significant implications for carbon capture. However, the traditional CaL requires a high temperature of 950 °C for CaCO3 decomposition, posing challenges for further development due to stringent temperature conditions. This study leverages the advantages of a hydrogen-rich reaction environment in a supercritical water gasification (SCWG) system to develop a thermodynamic model of a solar-driven SCWG system incorporating CaL. This innovation reduces the high-temperature requirement of traditional CaL by 41 %, lowering it to 560 °C, and simultaneously alleviates the coupling difficulty of solar-driven systems. The system utilises waste carbide slag (CS) to convert waste plastics into combustible CH4 and other industrial products, achieving thermochemical elimination of CO2 into CH4. Results indicate that CH4 production in traditional gasification systems increases with temperature, whereas the inclusion of CaL shows a trend of initial increase followed by a decrease, peaking at 560 °C with a 19.12 % increase compared to systems without CaL. Both energy and exergy efficiencies decline with temperature, while the impact of pressure on gasification performance and system efficiency remains below 10 %. Increasing the plastic-to-water ratio enhances CH4 production and energy and exergy efficiencies but reduces the gas yield per unit of plastic. © 2025

关键词： Exergy

来源：评论

学校读者我要写书评

暂无评论

Numerical Investigation of the Thermal Response to Skin Tissue during Laser Lipolysis

引用

Journal of Thermal Science 2018年第5期27卷 470-478页

作者： CHEN Bin ZHANG Yue LI Dong State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Laser lipolysis can effectively treat obesity and its associated diseases, such as hypertension, fatty liver, and hyperlipidemia. However, currently available invasive laser lipolysis, which transmits laser to a fiber-optic catheter inserted into the subcutaneous tissue for irradiation through an incision, may cause hematomas, infections, and empyrosis. The current study presents a novel, noninvasive approach for laser lipolysis, which directly irradiates the intact skin surface without an incision and preferentially targets adipose tissue at the near-infrared band. High laser energy is necessary to damage adipocytes; however, this may carbonate and burn the dermis. Therefore, the introduction of skin cooling is essential to avoid unwanted hyperthermal injury and improve the threshold of radiant exposure. In the current study, we investigated a novel noninvasive approach assisted with skin cooling by establishing a homogeneous multi-layer skin model. In this method, light propagation in the skin was simulated by using the Monte Carlo method. Skin cooling was employed before laser irradiation to protect the epidermis from thermal damage, which was treated as a boundary condition based on Newton's law. The numerical results showed that the photons were deposited in the adipose layer more than in the other layers. Laser can effectively destroy adipose tissue at an energy density of >200 J/cm^2 at 1210 nm wavelength, whereas at least 300 J/cm^2 is required at 1064 nm to achieve the same effect. In this experiment, at >5 s pulse width, the selectivity of adipose was not obvious. Moreover, the results indicated that 60 ms R134a or R404a spray can effectively reduce the temperature of the epidermis. R404a exhibited a stronger cooling effect than R134a. Cold air cooling at -10 °C for 10 s could effectively decrease the skin temperature, and deeper cooling could be achieved by cold air cooling compared with cryogen spray cooling.

关键词： laser lipolysis Nd:YAG laser multi-layer skin model skin cooling

来源：评论

学校读者我要写书评

暂无评论

Experimental Investigation on Heat Transfer Characteristics of Water in Inclined Downward Tube of a Supercritical Pressure CFB Boiler

引用

Journal of Thermal Science 2015年第5期24卷 478-487页

作者： WANG Siyang YANG Dong XIE Beibei WANG Long WANG Yongjie State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University

In this study, experiments have been performed for an investigation on heat transfer of water in an inclined downward tube with an inner diameter of 20 mm and an inclined angle of 45° from the horizon, with the range of pressure from 11.5 to 28 MPa, mass flux from 450 to 1550 kg/(m2 s), and heat flux from 50 to 585 k W/m2. Based on the experimental data, the temperature distribution in the tube wall was derived. The heat transfer characteristics of inclined downward flow were compared with that of vertical downward flow. The effects of heat flux on wall temperature were analyzed and the corresponding empirical correlations were presented. The results show that heat transfer characteristics of water in the inclined downward tube are not uniform along the circumference from the top surface to the bottom surface. An increase in heat flux exacerbates the non-uniformity. At subcritical pressures, both dry-out and departure from nucleate boiling(DNB) occur at the top surface of the inclined downward tube; inversely, only dry-out takes place on the bottom surface of the inclined downward tube and in the vertical downward tube. At near-critical pressures, DNB and dry-out occur in the comparing tubes with greater possibility. At supercritical pressures, heat transfer gets enhanced in the pseudo-critical enthalpy region; in the high enthalpy region, the top surface temperature of the inclined downward tube decreases obviously.

关键词： inclined downward tube wall temperature circumferential non-uniformity heat transfer deterioration

来源：评论

学校读者我要写书评

暂无评论

General analytical equation of state for nanoconfined gases derived from statistical physics

引用

Physical Review E 2025年第2期111卷 025413-025413页

作者： Chengzhen Sun Haoxuan Li Zhixiang Zhao Mehdi Neek-Amal Bofeng Bai State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an Shaanxi 710049 China School of Urban Planning and Municipal Engineering Xi'an Polytechnic University Xi'an Shaanxi 710048 China Department of Physics Faculty of Sciences Shahid Rajaee Teacher Training University 16875-163 Lavizan Tehran Islamic Republic of Iran Department of Physics University of Antwerp Groenenborgerlaan 171 2020 Antwerp Belgium

The pressure prediction of nanoconfined gases is crucial for various industrial applications, yet existing equations of state (EOS) often compromise between accuracy and usability. This study derives a theoretical EOS in analytical form, combining precision and practicality through statistical physics. It begins by examining the pressure drop mechanism due to adsorbed molecules and refines molecular pairing and potential energy interactions. The resulting EOS accurately predicts the pressure of gases in nanoconfined spaces, especially with an average prediction error of about 5% for strongly adsorbing gases like nitrogen, oxygen, and argon. Additionally, it aligns with the Van der Waals EOS under macroscopic conditions, offering a unified framework across scales. This model enhances both engineering applications and the understanding of nanoconfined EOS.

关键词： Van der Waals forces

来源：评论

学校读者我要写书评

暂无评论

Industrialization prospects for hydrogen production by coal gasification in supercritical water and novel thermodynamic cycle power generation system with no pollution emission

引用

Science China(Technological Sciences) 2015年第12期58卷 1989-2002页

作者： GUO LieJin JIN Hui GE ZhiWei LU YouJun CAO ChangQing State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Energy conversion and utilization, particularly carbon-based fuel burning in air phase, have caused great environmental pollution and serious problems to society. The reactions in water phase may have the potential to realize clean and efficient energy conversion and utilization. Coal gasification in supercritical water is a typical carbon-based fuel conversion process in water phase, and it takes the advantages of the unique chemical and physical properties of supercritical water to convert organic matter in coal to H2 and CO2. N, S, P, Hg and other elements are deposited as inorganic salts to avoid pollution emission. The State key laboratory of multiphase flow in power engineering has obtained extensive experimental and theoretical results based on coal gasification in supercritical water. Supercritical water fluidized bed reactor was developed for coal gasification and seven kinds of typical feedstock were selected. The hydrogen yield covers from 0.67 to 1.74 Nm3/kg and the carbon gasification efficiency is no less than 97%. This technology has a bright future in industrialization not only in electricity generation but also in hydrogen production and high value-added chemicals. Given the gas yield obtained in laboratory-scale unit, the hydrogen production cost is U.S.$ 0.111 Nm3 when the throughput capacity is 2000 t/d. A novel thermodynamic cycle power generation system based on coal gasification in supercritical water was proposed with the obvious advantages of high coal-electricity conversion efficiency and zero pollutant emission. The cost of U.S.$ 3.69 billion for desulfuration, denitration and dust removal in China in 2013 would have been saved with this technology. Five kinds of heat supply methods are analyzed and the rates of return of investment are roughly estimated. An integrated cooperative innovation center called a new type of high-efficient coal gasification technology and its large-scale utilization was founded to enhance the industrialization o

关键词： industrialization prospects hydrogen production supercritical water gasification power generation zero emission

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：