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Optoelectronics Letters 2024年第2期20卷 70-75页

作者： WANG Jiahui WEI Xian ZHU Yan SHEN Yue PANG Lipeng DUAN Shaoxiang Institute of Modern Optics Tianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyNankai UniversityTianjin 300350China Foreign Cooperation Projects Department of PetroChina Dagang Oilfield Company Tianjin 300280China The 58th Research Institute of China Electronics Technology Group corporation Wuxi 214035China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519000China1

We propose an in-fiber Michelson-Fabry-Perrot(M-FP)hybrid interferometer for the simultaneous measurement of seawater temperature and salinity.The sensor head consists of two parallel hetero Fabry-Perot(FP)cavities fabricated on the end face of the twin core fiber(TCF).A fiber fusion taper is used to split and recouple the light in the two cores.In this case,the Vernier effect can be obtained which can greatly enhance the sensitivity and solve the problem of temperature cross-sensitivity.Different from the traditional demodulation method based on envelop detection,we employed frequency domain decomposition method(FDDM)to demodulate the sensing signal.The simulation results indicate that the proposed sensor has high sensitivity to salinity and temperature.Thanks to the merits of high sensitivity,ease of fabrication and small footprint,the proposed seawater temperature and salinity sensor would have potential applications in marine science,food industry and ocean ranching.

关键词： temperature salinity ocean

Using tandem blades to break loading limit of highly loaded axial compressors

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Chinese Journal of Aeronautics 2022年第4期35卷 165-175页

作者： Baojie LIU Chuanhai ZHANG Guangfeng AN Du FU Xianjun YU Research Institute of Aero-Engine Beihang UniversityBeijing 100083China School of Energy and Power Engineering Beihang UniversityBeijing 100083China gree Electric Appliances Inc.of ZhuhaiZhuhai 519070China

It is confirmed that tandem-blade configurations have potential to enlarge the flow turning in two-dimension(2D) studies. However, the potential of tandem blades to enlarge the design space for highly loaded axial compressors was rarely investigated in open literatures. The present work aims to show the capability of tandem blades to break the loading limit of conventional blades for highly loaded compressors. The 2D models of the maximum static pressure rise derived in previous work were validated by a large amount experimental data, which showed a good agreement. An E parameter was defined to evaluate the stall margin of compressor based on the theoretical models, which indicated that the tandem blade was able to increase the loading limit of axial compressors. A single-blade stage with a loading coefficient of 0.46(based on the blade tip rotating speed) was designed as the baseline case under the guidance of the E parameter. A tandem-blade stage was then designed by ensuring that the velocity triangles were similar to the single-blade stage. The performances of both stages were investigated experimentally. The results showed that the maximum efficiency of the tandem-blade stage was 92.8%, 1% higher than the single;the stall margin increased from 16.9% to 22.3%. Besides, the maximum pressure rise of tandem rotors was beyond the loading limit of 2D single-blade cascades, which confirmed the potential of tandem blades to break the loading limit of axial compressors.

关键词： Cascades Highly loaded axial compressors Loading limit Single blades Tandem blades

Evaporating Temperature Uniformity of the Pulsating Heat Pipe with Surfactant Solutions at Different Concentrations

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Journal of Thermal Science 2023年第1期32卷 183-191页

作者： BAO Kangli WANG Xuehui ZHANG Peng-E HAN Xiaohong TAN Jianming State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation GREE Electric Appliances Inc.of ZhuhaiZhuhai 519070China Key Laboratory of Refrigeration and Cryogenic Technology of Zhejiang Province Institute of Refrigeration and CryogenicsZhejiang UniversityHangzhou 310027China

The evaporating section of the pulsating heat pipe(PHP)is in direct contact with the electronics when it is used for heat dissipation,and thus the evaporating temperature uniformity has an important effect on the safe and reliable operation of electronic equipment.On the basis of these conditions,an experimental study on the evaporating temperature uniformity of the PHP with surfactant solutions at different concentrations was conducted at the heat fluxes of(1911–19427)W/m^(2).Sodium stearate was utilized for the solute;the surfactant solutions were prepared with the concentrations of 0.001 wt%,0.002 wt%,and 0.004 wt%,respectively,and the filling ratios of the PHP were 0.31,0.44 and 0.57,respectively.The experimental results revealed that under all tested working conditions,the highest temperature always appeared in the intermediate zone of the evaporating section.As the heat flux increased,the temperature differences among different zones rose initially and then reduced due to the change of the flow motion and the flow pattern.The evaporating temperature uniformity of the sodium stearate solutions-PHP was better than that of the deionized water-PHP,which suggested that the evaporating temperature uniformity might be improved through decreasing the surface tension.Furthermore,combined with the effect of surface tension and viscosity,for different filling ratios,the required concentration was different when the best evaporating temperature uniformity was achieved.To be specific,when the filling ratio were 0.31 and 0.44,the best evaporating temperature uniformity was achieved at the concentration of 0.004 wt%,while at the filling ratio of 0.57,the best evaporating temperature uniformity was attained at the concentration of 0.002 wt%.

关键词： pulsating heat pipe surface tension evaporating temperature uniformity heat transfer

Simulation of thermal and humid environment of rural residence envelope inner surface during the plum rains season in Changsha China

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Energy and Built Environment

Energy and Built Environment 2023年第2期4卷 195-205页

作者： He Yecong Deng Qi Zhang Xiaofeng Liu Huaican School of Energy and Power Engineering Changsha University of Science and TechnologyChangsha 410114PR China State Key Laboratory of Air-conditioning Equipment and System Energy Conservation GREE Electric Appliances Inc.of ZhuhaiZhuhai 519070PR China

The Plum Rains Season(PRS)has the typical characteristics of outdoor air temperature dramatic changes and high air humidity in the hot summer and cold winter region in China.Even if the indoor heat source and moisture production is constant,when the outdoor air temperature rises rapidly during high air humidity PRS,the build-ing envelope temperature heats up much more slower than the indoor air temperature and therefore the wall surface temperature is lower than the indoor air dewpoint which leads to condensation phenomenon,resulting in deterioration of insulation performance,mouldy walls,deterioration of indoor air quality.At present,there is a lack of research on the factors affecting condensation in rural residence during PRS.This paper evaluates the impact of occupants’habit of window opening modes and building construction parameters on the building envelope surface condensation in Changsha during PRS.Using Designer’Simulation Toolkit(DeST)simulated and analysed the impact of key parameters such as window-to-wall ratio,exterior wall reflectivity,window opening mode(open/close),and external wall insulation on the building indoor thermal and humid environment.The condensation risk X is proposed to evaluate the condensation possibility on the building envelope’s inner sur-face.The results show that from the perspective of anti-condensation:The rural residential building in Changsha should balance the window-wall ratio against better natural lighting;Keeping windows closed during PRS can effectively alleviate the condensation problem while the insulation in the external wall layer could aggravate the condensation.

关键词： Plum rains season(PRS) Condensation risk Building envelope Window-wall ratio External wall reflectivity

Heat Transfer of Boiling R134a and R142b on a Twisted Tube with Machine Processed Porous Surface

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Chinese Journal of Chemical Engineering 2008年第3期16卷 492-496页

作者：高学农尹辉斌黄玉优凌双梅张正国方玉堂 Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education South China University of Technology Guangzhou 510640 China zhuhai gree corporation Zhuhai 519070 China

这个工作的目的是调查起核心作用有机器的一个扭曲的试管上的 R134a 和 R142b 的水池沸腾传热性能和机制处理了多孔的表面(T-MPPS 试管) 象一样决定它的潜在的申请到充满的致冷的蒸发器。在试验性的范围，一个 T-MPPS 试管上的 R134a ... 详细信息

这个工作的目的是调查起核心作用有机器的一个扭曲的试管上的 R134a 和 R142b 的水池沸腾传热性能和机制处理了多孔的表面(T-MPPS 试管) 象一样决定它的潜在的申请到充满的致冷的蒸发器。在试验性的范围，一个 T-MPPS 试管上的 R134a 的沸腾传热系数是光管上的 R134a 的比那些大的 1.8-2.0 时间。另外，发达试验性的关联证实以试验性的条件在一个 T-MPPS 试管上煮 R134a 和 R142b 的传热系数的预言是更加精确的。

关键词： R134a R142b 表面多孔螺旋扁管沸腾传热

Studies on Performance of Distributed Vertical Axis Wind Turbine under Building Turbulence

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Energy Engineering 2023年第3期120卷 729-742页

作者： Xin Sun Chi Zhang Yan Jia Shikang Sui Chong Zuo Xueqiang Liu School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010051China Key Laboratory of Wind Energy and Solar Energy Utilization Technology Ministry of EducationInner Mongolia University of TechnologyHohhot010051China gree Electric Appliances.Inc.of zhuhai Zhuhai519000China

As a part of the new energy development trend,distributed power generation may fully utilize a variety of decentralized energy sources.Buildings close to the installation location,besides,may have a considerable impact on the wind turbines’operation.Using a combined vertical axis wind turbine with an S-shaped lift outer blade and-shaped drag inner blade,this paper investigates how a novel type of upstream wall interacts with the incident wind at various speeds,the influence region of the turbulent vortex,and performance variation.The results demonstrate that the building’s turbulence affects the wind’s horizontal and vertical direction,as well as its speed,in downstreamplaces.The wall’s effect on wind speed changing in the downstreamarea is thoroughly investigated.It turns out that while choosing an installation location,disturbing flow areas or low disturbing flow zones should be avoided to have the least impact on wind turbine performance.

关键词： Vertical axis wind turbine building turbulence CFD sliding mesh installation position

多孔g-CN和碳化三聚氰胺泡沫的一体化构筑促进光催化分解水蒸气（英文）

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Science China Materials 2024年

作者：王树建柳东杰张春阳黄婕赵仕东吕科见王标彭好司亦涛刘茂昌 International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University School of Chemistry and Chemical Engineering Southeast University Suzhou Academy of Xi'an Jiaotong University gree Altairnano New Energy Inc.

本文报道了一种光热诱导的液-固/气-固解耦光催化分解水系统,其中碳化的三聚氰胺泡沫(CMF)和多孔g-C3N4(PCN)分别作为光热基底材料和模型光催化剂. CMF通过其光热效应将液态水转化为水蒸气,随后产生的水蒸气通过PCN光催化剂转化为氢气....

本文报道了一种光热诱导的液-固/气-固解耦光催化分解水系统,其中碳化的三聚氰胺泡沫(CMF)和多孔g-C3N4(PCN)分别作为光热基底材料和模型光催化剂. CMF通过其光热效应将液态水转化为水蒸气,随后产生的水蒸气通过PCN光催化剂转化为氢气.该新型两相光催化体系的光催化速率高达368.1μmol h-1,分别是传统三相P C N体系(151.7μmol h-1)和CN体系(14.4μmol h-1)的2.4和25.6倍.光催化性能的提高主要归因于该系统优化了气-液-固反应界面的能量和物质传递,实现了光催化过程中气体产物的快速脱附.这项工作从能量流和质量流角度为光催化分解水提供了新的思路.

关键词：

Risk Evaluation of Ammonia Leakage based on Modified Probability Calculation Formulas

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Journal of Thermal Science 2023年第2期32卷 854-865页

作者： GE Yingying YANG Zhao HE Hongxia WU Xiaokun CHEN Yubo LV Zijian ZHANG Yong Key Laboratory of Efficient Utilization of Low and Medium Grade Energy MOESchool of Mechanical EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation GREE Electric AppliancesInc.of ZhuhaiGuangdong 519070China

Due to its flammable,explosive,and corrosive characteristics,fire,and explosion accidents caused by ammonia leakage occur from time to time.In this work,the concentration distribution of the model was calculated according to the existing formula of probabilistic risk assessment.Using the revised formulas,the leakage of the ammonia room was quantitatively analyzed,and different state parameters were analyzed to find out the dangerous leakage points of the ammonia refrigeration system.The results of the calculation are that the existence of obstacles in the space will increase the probability of leakage risk.And the greater the leakage time to the lower flammability limit accounts for the total leakage time,the greater the risk probability.Dangerous leakage in ammonia systems mainly occurs in storage tanks and condensers.The data show that the dynamic mass flow of ammonia leakage decreases with time,and the leakage diameter increases with the increase of leakage pressure.At the same time,the leakage mass increases gradually with the leakage aperture near circular.

关键词： flammable refrigerants leakage risk evaluation of fire probability calculation

Finite Element Modeling and Vibration Analysis of Sprag Clutch⁃Flexible Rotor System

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Journal of Harbin Institute of Technology(New Series) 2022年第2期29卷 13-23页

作者： Chuang Huang Yongqiang Zhao Guanghu Jin School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China gree Electric Appliances Inc.of ZhuhaiZhuhai 519070GuangdongChina National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To study the overall vibration characteristics of the sprag clutch⁃flexible rotor system(SC⁃FRS)under high⁃speed operating conditions,a finite element model of SC⁃FRS considering rotor flexibility and bearing support stiffness was established based on the proposed calculation method of the stiffness matrix.According to this model,the natural frequency and mode shape of the system are calculated,and the correctness of the model was verified by comparing it with the calculation results of ANSYS software.Under the action of unbalance,the bending⁃torsion coupled vibration and the dynamic load of the inter⁃shaft bearings were analyzed,and it is found that the resonant peak in the torsional direction has the same resonance frequency as that in the bending direction.A test rig for the sprag clutch⁃rotor system was built,and the axis trajectory and critical speed were tested.The test results show that the finite element model of SC⁃FRS can accurately describe the vibration characteristics of the system.The coupling vibration characteristics analysis of the sprag clutch⁃flexible rotor system can provide theoretical guidance for the dynamic design of the sprag clutch components.

关键词： sprag clutch⁃rotor system finite element model unbalanced mass experimental verification

On the turbulent heat fluxes:A comparison among satellite-based estimates,atmospheric reanalyses,and in-situ observations during the winter climate over Arctic sea ice

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Advances in Climate Change Research 2023年第3期14卷 347-362页

作者： Zhi-Lun ZHANG Feng-Ming HUI Timo VIHMA Mats A.GRANSKOG Bin CHENG Zhuo-Qi CHEN Xiao CHENG School of Geospatial Engineering and Science Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-sen University) Ministry of EducationZhuhai 519082China University corporation for Polar Research Beijing 100032China Finnish Meteorological Institute Helsinki 00560Finland Norwegian Polar Institute Fram CentreTromsøN-9296Norway

The surface energy budget is crucial for Arctic sea ice mass balance calculation and climate systems,among which turbulent heat fluxes significantly affect the airesea exchanges of heat and moisture in the atmospheric boundary layer.Satellite observations(e.g.CERES and APPX)and atmospheric reanalyses(e.g.,ERA5)are often used to represent components of the energy budget at regional and pan-Arctic scales.However,the uncertainties of the satellite-based turbulent heat fluxes are largely unknown,and cross-comparisons with reanalysis data and insitu observations are limited.In this study,satellite-based turbulent heat fluxes were assessed against in-situ observations from the N-ICE2015 drifting ice station(north of Svalbard,JanuaryeJune 2015)and ERA5 reanalysis.The turbulent heat fluxes were calculated by two approaches using the satellite-based ice surface temperature and radiative fluxes,surface atmospheric parameters from ERA5,and snow/sea ice thickness from the pan-Arctic Ice Ocean Modeling and Assimilation System(PIOMAS).We found that the bulk-aerodynamic formula based results could better capture the variations of turbulent heat fluxes,while the maximum entropy production based estimates are comparable with ERA5 in terms of root-mean-square error(RMSE).CERES-based estimates outperform the APP-X-based ones but ERA5 performs the best in all seasons(RMSE of 18 and 7 W m^(-2)for sensible and latent heat flux,respectively).The aireice temperature/humidity differences and the surface radiation budget were found the primary driving factors in the bulk-formula method and maximum entropy production(MEP)method,respectively.Furthermore,errors in the surface and near-surface temperature and humidity explain almost 50%of the uncertainties in the estimates based on the bulk-formula,whereas errors in the net radiative fluxes explain more than 50%of the uncertainties in the MEP-based results.

关键词： Arctic sea ice Surface energy budget Turbulent heat flux Satellite observation Reanalysis Bulk-aerodynamic formula Maximum entropy production