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Thermal shock damage behavior of CVD ZnS by oxygen propane flame: A numerical and experimental study

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Chinese Journal of Aeronautics 2014年第2期27卷 266-271页

作者： Liu Yuanchun He Yurong tian fenglin Zhu Jiaqi School of Energy Science & Engineering Harbin Institute of Technology Center of Composite Materials Harbin Institute of Technology

Chemical vapor deposition zinc sulfide （CVD ZnS） is widely used as an infrared window material to transmit infrared signals, keep the aerodynamic shape and protect its imaging system, which often suffers high temperature and complicated thermal stresses. The purpose of this paper is to investigate the thermal shock damage of CVD ZnS through a finite element method and oxygen propane flame experiments. The finite element model is developed to simulate the temperature and thermal stress fields by an oxygen propane flame. Then, the thermal shock experiments are performed to investigate the thermal shock damage behavior. The results show that the temperature rising rate of the shock surface is fast during the initial heating stage resulting in high thermal stress. After the thermal shock experiment, the scanning electron microscope （SEM） photographs shows that the shock surface of the specimen becomes rough and the microcracks occur in the thermal shock zone. Good agreements are achieved between the numerical solutions and the experimental results.

关键词： CVD ZnS Damage behavior Finite element method,Oxygen propane flame Thermal shock

Lagrangian eddies in the Northwestern Pacifi c Ocean

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Journal of Oceanology and Limnology 2022年第1期40卷 66-77页

作者： Qiu HE fenglin tian Xiaokun YANG Ge CHEN Department of Marine Technology College of Information Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518034China

The Lagrangian eddies in the western Pacifi c Ocean are identifi ed and analysed based on Maps of Sea Level Anomaly(MSLA)data from 1998 to *** calculating the Lagrangian eddy advected by the AVISO velocity fi eld,we analyzed the variations in Lagrangian eddies and the average transport eff ects on diff erent time *** introducing the Niño coeffi cient,the lag response of the Lagrangian eddy to El Niño is *** data are helpful to further explore the role of mesoscale eddies in ocean energy *** normalized chlorophyll data,we observed chlorophyll aggregation and hole eff ects caused by Lagrangian *** fi ndings demonstrate the important role of Lagrangian eddies in material *** transportation volume of the Lagrangian eddy is calculated quantitatively,and several major transport routes have been identifi ed,which helps us to more accurately and objectively estimate the transport capacity of Lagrangian eddies in the western Pacifi c Ocean.

关键词： Lagrangian coherent structure(LCS) mesoscale eddy distribution character material transport

The geometry of mesoscale eddies in the South China Sea: characteristics and implications

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International Journal of Digital Earth 2021年第4期14卷 464-479页

作者： Guiyan Han fenglin tian Chunyong Ma Ge Chen Department of Marine Technology Institute for Advanced Ocean StudyOcean University of ChinaQingdaoPeople’s Republic of China Qingdao National Laboratory for Marine Science and Technology QingdaoPeople’s Republic of China

The symmetrical circular shape of mesoscale eddies has been widely used in their scientific ***,an elliptical average eddy shape has been confirmed for eddies in the global ocean using multi-satellite altimeter *** a regional extension of a previous study on the geometry of global eddies,a mean eddy shape in the South China Sea(SCS)has been derived by averaging a large number of orientational eddy *** mean shape is approximately a mathematic ellipse with a semimajor axis of 101.3 km and a semiminor axis of 61.3 *** size is larger than the global *** principal eddy orientation in the SCS is 74°/254°(nearly northeast-southwest),different from that of eddies in the global ocean(171°/351°,nearly east–west).Composite analyses of chlorophyll(CHL)concentrations and sea surface temperature anomalies(SSTA)indicate a dipole structure for circular eddies in the non-rotated coordinate *** a monopole structure for elliptical eddies in the eddy-centric coordinate system is *** results demonstrate that the elliptical shape of eddies affects oceanographical *** findings provide a new approach for exploring the role of air–sea interactions on oceanic eddies.

关键词： Mesoscale eddies eddy shape eddy orientation South China Sea

i4Ocean: transfer function-based interactive visualization of ocean temperature and salinity volume data

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International Journal of Digital Earth 2021年第6期14卷 766-788页

作者： fenglin tian Qing Mao Yazhen Zhang Ge Chen Department of Marine Technology Ocean University of ChinaQingdaoPeople’s Republic of China Qingdao National Laboratory for Marine Science and Technology QingdaoPeople’s Republic of China

In this paper,we present a novel ocean visualization framework,which focuses on analyzing multidimensional and spatiotemporal ocean ***-based visualization methods are explored to effectively visualize ocean *** improved ray casting algorithm for heterogeneous multisection ocean volume data is presented.A two-layer spherical shell is taken as the ocean data proxy geometry,which enables oceanographers to obtain a real geographic background based on global *** efficient ray sampling technique including an adaptive sampling technique and a preintegrated transfer function is proposed to achieve high-effectiveness and high-efficiency ***,an interactive transfer function is also designed to analyze the 3D structure of ocean temperature and salinity anomaly *** on the framework,an integrated visualization system called i4Ocean is *** visualization of ocean temperature and salinity anomalies extracted interactively by the transfer function is demonstrated.

关键词： Ocean temperature and salinity data ray casting algorithm transfer function spherical volume rendering GPU

Three-dimensional mesoscale eddy identification and tracking algorithm based on pressure anomalies Liming

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Journal of Oceanology and Limnology 2021年第6期39卷 2153-2166页

作者： Liming YUAN fenglin tian Suqin XU Chun ZHOU Jie CHEN CSSC Ocean Exploration Technology Institute Co. Ltd.Wuxi 214000China College of Information Science and Engineering Ocean University of ChinaQingdao 266100China PLA Naval Submarine Academy Qingdao 266199China

The Kuroshio Extension(KE)is one of the most eddy-energetic regions in the global ***,most mesoscale eddy studies in the region are focused on surface eddies and the structure and characteristics of three-dimensional(3-D)eddies require additional *** this study,we proposed a 3-D eddy identification and tracking algorithm based on pressure anomalies,similar to sea level anomalies(SLAs)for surface eddy *** applied this scheme to a 5-year(2008-2012)high-resolution numerical product to develop a 3-D eddy dataset in the *** reliability of the numerical product was verified by the 5-year temperature/salinity hydrological characteristics and surface eddy *** to the 3-D eddy tracking dataset,the number of eddies decreased dramatically as the eddy existence-time increased and more anticyclonic eddies(AEs)had an existence-time longer than 1 week than cyclonic eddies(CEs).We presented daily variations in the 3-D structure of two 3-D eddy-tracking trajectories that exhibit a certain jump in depth and a shift toward the west and *** addition to the bowl,lens,and cone eddies that have been discovered by previous researchers,we found that there is a cylindrical eddy,and its eddy radii are almost consistent across all *** cause significant negative temperature anomalies,“negative-positive”salinity anomalies,and sinking current fields in the KE region,while AEs cause positive temperature anomalies,“positive-negative”salinity anomalies,and upward current *** four types of eddies have different effects on the temperature/salinity anomalies and current field distribution which are related to their structure.

关键词： mesoscale eddy pressure anomalies three-dimensional structure identification tracking

A Real-Time Photo-Realistic Rendering Algorithm of Ocean Color Based on Bio-Optical Model

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Journal of Ocean University of China 2016年第6期15卷 996-1006页

作者： MA Chunyong XU Shu WANG Hongsong tian fenglin CHEN Ge College of Information Science and Engineering Ocean University of China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology

Abstract A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton, colored dissolved organic material （CDOM）, inorganic suspended particle, etc., which have different contributionsto absorption and scattering of light. We decompose the emergent light of the ocean surface into the reflected light from the sun and the sky, and the subsurface scattering light. We estab- lish an ocean surface transmission model based on ocean bidirectional reflectance distribution function （BRDF） and the Fresnel law, and this model＇s outputs would be the incident light parameters of subsurface scattering. Using ocean subsurface scattering algorithm combined with bio-optical model, we compute the scattering light emergent radiation in different directions. Then, we blend the re- flection of sunlight and sky light to implement the real-time ocean color rendering in graphics processing unit （GPU）. Finally, we use two kinds of radiance reflectance calculated by Hydrolight radiative transfer model and our algorithm to validate the physical reality of our method, and the results show that our algorithm can achieve real-time highly realistic ocean color scenes.

关键词： ocean color BRDF subsurface scattering bio-optical model

Geographical Information Visualization on a Panoramic Sphere in an Immersive Environment

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Journal of Ocean University of China 2023年第4期22卷 961-974页

作者： MA Ying tian fenglin LIU Wen TANG Moran LI Jinyu CHEN Ge Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266100China Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China

In this paper,we propose a novel approach to visualizing global geographical information:a panoramic sphere in an immersive *** whole geographical surface can be observed through the rotating of heads as the viewpoint of the panoramic sphere is inside the *** compared three approaches to visualizing the earth for rendering the geographical information in a virtual reality *** the tasks of terrestrial and marine geographical information,we compare the visualization effects on a)a globe,b)a flat map and c)a panoramic *** geographical information tasks include the area comparison and direction *** geographical information tasks contain the visualization of sea surface temperature and sea surface *** terrestrial geographical information tasks,the experimental results show that the panoramic sphere outperforms the globe and the flat map,with a higher average accuracy and a shorter *** marine geographical information task,the panoramic sphere visualization is also superior to the flat map and the globe in an immersive environment for the sea surface temperature data and the sea surface current *** all three visualization experiments,the panoramic sphere is most preferred by the participants,particularly for global,transcontinental and transoceanic needs.

关键词： the panoramic sphere immersive environment virtual reality oceanographic information visualization

Design and Implementation of a 3D Ocean Virtual Reality and Visualization Engine

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Journal of Ocean University of China 2012年第4期11卷 481-487页

作者： CHEN Ge LI Bo tian fenglin JI Pengbo LI Wenqing Department of Marine Technology Ocean University of ChinaEngineering Research Center of Marine Information TechnologyMinistry of EducationQingdao 266100P.R.China School of Resources and Environment South West Petroleum UniversityChengdu 610500P.R.China Institute of Oceanographic Instrumentation Shandong Academy of SciencesQingdao 266001P.R.China

In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine *** design goals of VV-Ocean aim at high fidelity simulation of ocean environment,visualization of massive and multidimensional marine data,and imitation of marine ***-Ocean is composed of five modules,*** management module,resources management module,scene management module,rendering process management module and interaction management *** are three core functions in VV-Ocean:reconstructing vivid virtual ocean scenes,visualizing real data dynamically in real time,imitating and simulating marine lives *** on VV-Ocean,we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to *** factors such as ocean current and wind field have been considered in this *** this platform oil spilling process can be abstracted as movements of abundant oil *** result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive ***-Ocean can be widely used in ocean applications such as demonstrating marine operations,facilitating maritime communications,developing ocean games,reducing marine hazards,forecasting the weather over oceans,serving marine tourism,and so ***,further technological improvements of VV-Ocean are discussed.

关键词： ocean rendering engine virtual reality visualization imitation of marine lives oil spilling simulation

GPU Accelerated Marine Data Visualization Method

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Journal of Ocean University of China 2014年第6期13卷 964-970页

作者： LI Bo CHEN Ge tian fenglin SHAO Baomin JI Pengbo Department of Marine Technology Ocean University of ChinaEngineering Research Center of Marine Information TechnologyMinistry of Education Shandong Provincial Key Laboratory of Optical Astronomy and Solar Environment Institute of Space SciencesShandong University Institute of Oceanographic Instrumentation Shandong Academy of Science

The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean model and visualizing model results have become some of the most important research topics of ‘Digital Ocean'. In this paper, a spherical ray casting method is developed to improve the traditional ray-casting algorithm and to make efficient use of GPUs. Aiming at the ocean current data, a 3D view-dependent line integral convolution method is used, in which the spatial frequency is adapted according to the distance from a camera. The study is based on a 3D virtual reality and visualization engine, namely the VV-Ocean. Some interactive operations are also provided to highlight the interesting structures and the characteristics of volumetric data. Finally, the marine data gathered in the East China Sea are displayed and analyzed. The results show that the method meets the requirements of real-time and interactive rendering.

关键词： marine data visualization techniques and methodologies spherical ray casting line integral convolution multiquadric method VV-Ocean