Keynote & Programme

The programme will be available soon.

Pr. Li Chen

Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power Engineering Xi’an Jiaotong University, China

Li Chen obtained his PH. D at Xi’an Jiaotong University in 2013, followed by a Director Postdoc at Los Alamos National Lab from 2013.12 to 2015.12. His research focuses on transport phenomena in porous media with background of fuel cells, oil/gas exploitation, CO2 subsurface sequestration, thermochemical energy storage, etc. He has developed an advanced pore-scale model for coupled multiphase flow, heat and mass transfer, chemical reaction, solid precipitation-dissolution (melting-solidification) processes in porous media. Up to now, he has published 68 SCI peer-reviewed papers in a variety of journals, including International Journal of Heat and Mass Transfer, Journal of Power Sources, Nano Energy, Applied Energy, Langmuir, Journal of Computational Physics, Physical Review E, Fuel, Electrochemica Acta, Water Resources Research, etc. His publications have been cited over 3200 times, with personal H index as 29. He has also been invited 5 times to contribute chapters in several books, 10 times for invitation talks on international conference and workshop. He won Young Scientist award of Asian Union of Thermal Science and Engineering. He is in the editor board of international journal Frontiers in Heat and Mass Transfer.

Multiscale modeling of multiphase flow and reactive transport in proton exchange membrane fuel cells

Li Chen, Wen-Quan Tao

Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, 710049, China

Proton exchange membrane fuel cell (PEMFC) is a promising and attractive candidate for a wide variety of power applications such as fuel cell vehicles, due to its advantages including high energy density, high efficiency, low operating temperature, and quick start-up. Currently, there are several challenges remaining for commercialization of PEMFC including performance, durability and cost. A deep understanding of the coupled transport processes in PEMFC is of great importance for improving cell performance and reducing system cost.

During the past 10 years in our group, advanced multi-scale numerical methods have been developed to study the physical-chemical-thermal processes in PEMFCs. Pore-scale models based on the Lattice Boltzmann method (LBM) are proposed to study multiphase flow, heat and mass transfer and electrochemical reaction in gas diffusion layer and catalyst layer. Permeability, effective diffusivity and thermal conductivity of the porous electrodes are predicted. Effects of pore structures and surface wettability on liquid water and distributions are studied. Local transport resistance across the pore-ionomer interface in nanoscale catalyst layer is investigated. Based on the pore-scale study, structures of the porous electrodes are optimized to alleviate flooding, enhance mass transport and reduce cell cost.

Multi-scale numerical method is then developed by upscaling the pore-scale sub-grid models into cell-scale models. Transport resistance under high current density and low Pt loading is accurately predicted. The proposed multi-scale modeling method provides a powerful tool for improving the cell performance and reducing the cell cost.

chen

Pr. Francisco Chinesta

Processes and Engineering in Mechanics and Materials, Arts et Métiers Institute of Technology, Paris, France

Francisco Chinesta is currently full Professor of computational physics at ENSAM Institute of Technology (Paris, France), Honorary Fellow of the “Institut Universitaire de France” – IUF- and Fellow of the Spanish Royal Academy of Engineering. He is the president of the ESI Group scientific committee and director of its scientific department. He was (2008-2012) AIRBUS Group chair professor and since 2013 he is ESI Group chair professor on advanced modeling and simulation of materials, structures, processes and systems. He received many scientific awards (among them the IACM -International Association of Computational Mechanics- Zienkiewicz award (New York, 2018), the ESAFORM award, …) in four different fields: bio-engineering, material forming processes, rheology and computational mechanics (with major contributions in Model Order Reduction and Engineered Artificial Intelligence, both integrated in the so-called Hybrid paradigm of Simulation Based Engineering). He is author of more than 320 papers in peer-reviewed international journals and more than 900 contributions in conferences. He was president of the French association of computational mechanics (CSMA) and is director of the CNRS research group (GdR) on model order reduction techniques in engineering sciences, editor and associate editor of many journals. He received many distinctions, among them the Academic Palms, the French Order of Merit, … in 2018 the Doctorate Honoris Causa at the University of Zaragoza (Spain) and in 2019 the Silver medal from the French CNRS.

Towards real-time reliable simulations of heat, mass and momentum transfer by combining model order reduction and artificial intelligence.

Francisco Chinesa, ENSAM Institute of Technology (Paris, France)

In the past fast and accurate implied in general apposite routes: when looking for rapidity, models were degraded with the consequent effects when certifying solutions. On the other hand, when looking for accuracy, rich high-fidelity simulations implied tremendous computational efforts, and the associated computing time. Today, the use of advanced model order reduction allows solving models under the stringent real-time constraint, calibrating them my assimilating data also in real-time, and when discrepancies are observed with respect to measurements, models can be enriched by using advanced physics-aware artificial intelligence, within a hybrid paradigm allying the analogic world of the knowledge and the digital world of data. In this presentation, that hybrid paradigm will be applied to heat, mass and momentum transfer.

 

chinesta

Dr. Barbaros Çetin

Assoc. Prof. Dr. Microfluidics & Lab-on-a-chip Research Group, Mech. Eng. Dept., İ.D. Bilkent University

Dr. Barbaros Çetin received his B.S. (2002) and M.S. (2005) in Mechanical Engineering at Middle East Technical University, Ankara, Turkey. He received his PhD (2009) in the Department of Mechanical Engineering at Vanderbilt University where he focused on electrokinetic transport and particle manipulation in lab-on-a-chip devices for biomedical applications. Following his PhD, he became a faculty member in Middle East Technical University-Northern Cyprus Campus Mechanical Engineering Program. In 2011, he became a faculty member in the Mechanical Engineering Department at I.D. Bilkent University, Ankara, Turkey. His current research interests include particle manipulation for microfluidic applications, modeling of particle motion using boundary element method, and modeling, fabrication and experimentation of flat-grooved heat pipes. Dr. Çetin is the recipient of the 2015 Bilkent University Distinguished Teacher Award, 2017 Outstanding Young Scientist Award of the Turkish Academy of Sciences (TÜBA-GEBİP), 2017 METU Prof. Dr. Mustafa N. Parlar Research Incentive Award and 2018 Science Academy Association Distinguished Young Scientist Award (BAGEP).

Modeling of Bio-particle Motion in Microchannels

Assoc. Prof. Dr. Barbaros Çetin

Microfluidics & Lab-on-a-chip Research Group, Mech. Eng. Dept., İ.D. Bilkent University

Manipulation of the biological particles is the main ingredient for many microfluidic applications. Modeling of the motion of particles with different geometry and size in microchannels is crucial for the design of microfluidic platforms. For the manipulation of particles, there are passive hydrodynamic techniques which utilizes the channel geometry and flow field as well as active techniques which employs external forces such as electric, acoustic, magnetic and/or optic. For microfluidic applications, there are commonly two approaches to simulate the particle trajectories: (i) Lagrange tracking method, (ii) stress tensor method. In Lagrange tracking method, flow, electric and/or acoustic fields are obtained by neglecting the presence of particles (i.e. assuming particles as point particles). This approach is acceptable when the size of the particles is small relative to the microchannel, and for the dilute solution in which the particle-particle interactions can be neglected. In stress tensor method, the field variables are determined with presence of the finite particle size. In this approach, resulting forces and torques acting on the particles are obtained by integrating the corresponding tensors. Therefore, particle-particle and/or particle-wall interactions can be captured. Volume based numerical models are faced with algorithmic and computational challenges in resolving complex particle shapes and in efficient implementation of particle motion. In addition, resolution of interactions between close particles and surfaces often require unusually high mesh density. These challenges are eliminated by using the Boundary Element Method (BEM) that requires discretization of the particle and channel surfaces, which effectively reduces 3D problems to 2D, and 2D problems to 1D. In addition, the derivative of the field variables which are essential for calculation of the forces acting on the particles comes as a part of the solution without requiring any numerical approximation. In this talk, different modelling strategies will be discussed and modeling of different cases for hydrodynamic, electrokinetic and acoustophoretic bioparticle manipulation will be presented.

barbaros

Julien Guihaire

Department of Cardiac Surgery, Research and Innovation Unit, RHU BioArt Lung 2020, Marie Lannelongue Hospital, Paris-Saclay University Medical School, Le Plessis-Robinson, France
  • Cardiac surgeon, Marie Lannelongue Hospital, Groupe Hospitalier Paris St Joseph, University of Paris Saclay
  • Head of the Heart Transplantation and Mechanical Circulatory Support program at Marie Lannelongue Hospital
  • Scientific advisor of the Preclinical Research Unit at Marie Lannelongue Hospital
  • 2019 Norman E. Shumway Career Development Award, International Society for Heart and Lung Transplantation
  • Main research topics:
    1. Improvement of cardiac allograft assessment during ex vivo perfusion
    2. Physiology of the assisted circulation
    3. Pathophysiology of right heart failure

Recent update and controversies of continuous flow physiology for durable mechanical circulatory support

Julien Guihaire, MD. PhD.

Mechanical circulatory support has changed the prognosis of patients with advanced heart failure, especially for those with limited access to heart transplantation. Pulsatile flow (PF) pumps were first developed and applied in the mid 1990’s. However these devices were voluminous and required partial or complete extracorporeal implantation. Major technological advances have been observed over the past two decades, resulting in miniaturization of the devices along with the development of a new physiological approach. Current devices actually provide continuous flow (CF) to the systemic circulation. Long-term impact of CF-devices is more complex than simply the lack of pulsatility, as illustrated by the increased risk of aortic root thrombosis, red blood cell injury, as well as platelet activation. Impaired renal function, gastrointestinal bleeding, arteriovenous malformations, are other consequences of the long-term absence of PF. Theses complications result in reduced survival over two years after implantation of CF device. Recent centrifugal CF pumps seem however to be associated with a better hemocompatibility, in part as a result of artificial pulsatility. Another major feature of pulsatile flow is to deliver kinetic energy to the vasculature. While the aorta and its collateral branches share a high compliance, arterioles and capillaries have a lower compliance and a higher resistivity. End-organ perfusion is therefore more dependent of pulse pressure for than of mean

flow velocity. We sought to report recent updates and persistent controversies of CF mechanical circulatory support.

GuihaireJulien

Pr. Yogesh Jaluria

Department of Mechanical and Aerospace Engineering. Rutgers, The State University of New Jersey, USA.

Professor Yogesh Jaluria is Board of Governors Professor and Distinguished Professor at Rutgers, the State University of New Jersey. His research work is in the field of thermal science and engineering, covering areas like convection, computational heat transfer, fires, materials processing and manufacturing, thermal management of electronics, energy, environment, and optimization of thermal systems. He is the author/co-author of 10 books. He is the editor/coeditor of fifteen conference proceedings, eleven books, and thirteen special issues of archival journals. He has contributed over 500 technical articles, including over 220 in archival journals and 19 book chapters. He has received several awards and honors for his work, such as the prestigious 2020 Holley Medal from the American Society of Mechanical Engineers (ASME) for his work on optical fiber drawing, 2010 A.V. Luikov Award from the International Center for Heat and Mass Transfer in recognition of outstanding work done over the career, 2007 Kern Award from American Institute of Chemical Engineers (AIChE) for outstanding contributions to heat transfer or energy conversion, the 2003 Robert Henry Thurston Lecture Award from ASME, and the 2002 Max Jakob Memorial Award, the highest international recognition in heat transfer, from ASME and the AIChE. He received the 2000 Freeman Scholar Award, the 1999 Worcester Reed Warner Medal, and the 1995 Heat Transfer Memorial Award all from ASME. He has served as Department Chairman and as Dean of Engineering. He was the Editor of the Journal of Heat Transfer (2005-2010), and Computational Mechanics (2003-2005). He is an Honorary Member of ASME, a Fellow of AAAS and APS, an Associate Fellow of AIAA and member of other professional societies. He served as the founding President of the American Society of Thermal and Fluids Engineers (ASTFE) from 2014 to 2019.

Optimization of Thermal Systems to Enhance Output and Reduce Energy Consumption and Environmental Effect

Yogesh Jaluria
Board of Governors Professor and Distinguished Professor
Mechanical and Aerospace Engineering Department
Rutgers University, Piscataway, New Jersey, USA

It has become critical to optimize process and systems in order to reduce energy consumption and the environmental effect, while increasing the productivity and product quality. Thermal systems, which are based on heat and mass transfer, fluid flow and thermodynamics, arise in a wide variety of applications and it is particularly important to optimize these. This presentation discusses the optimization of thermal systems and processes to achieve the best output with respect to energy and the environment. Systems from several important application areas, such as manufacturing, thermal management of electronics, heating/cooling and heat rejection are considered. Thermal systems and processes are generally quite complex due to variable material properties, uncertainties, combined transport mechanisms, complex domains, complicated boundary conditions, and multi-scale phenomena. Therefore, the modelling and simulation of these systems is quite involved and considerable care is needed to obtain accurate results. Simulation results, along with experimental data, are used for prediction of the behaviour of systems, as well as their design and optimization. The paper focuses on the reduction in energy and material consumption and in the effect on the environment. However, it is also important to enhance the output and improve the quality of the product obtained. The important aspects that must be considered and the approaches that may be adopted to obtain an accurate model and an optimal design are discussed in detail. In most practical situations, several objectives are of interest and multi-objective design optimization is necessary. Results for a few important systems, such as those for power plant heat rejection, materials processing and thermal management of data centres, are presented in order to illustrate the basic approach. Additional concerns and approaches are outlined for other important processes.

 

jaluria

Dr. Paweł Ocłoń

Associate Professor in the Energy Department at Cracow University of Technology

Paweł Ocłoń (PhD. Dr-Hab, Associate Prof of CUT.) works as Associate Professor in the Energy Department at Cracow University of Technology. He graduated from the Faculty of Mechanical at Cracow University of Technology in 2008, and received a Mechanical Engineering MSc Degree in 2008, PhD Degree in 2013, and Habilitation in 2016. All those scientific degrees were awarded with distinction Prof. Ocłoń recieved prestigues awards for his recent scientific achievements including 1st Degree Award of Polish Ministry of Science and Higher Education for Scientific Achievements (2017) – one of the most prestige’s awards in Polish Science. 3 years fellowship of Polish Ministry of Science and Higher Education for Outstanding Young Scientists (2017-2020). Best publishing habilitated doctor of Mechanical Engineering Faculty award (2019). Prof. Ocłoń also received in total 6 Cracow University of Technology Rector’s awards for his scientific achievements in years 2015-2020.

Prof. Ocłoń has published 63 ISI indexed papers on topics related with heat transfer, energy engineering and fluid dynamics. Prof. Ocłoń is regular reviewer of ISI indexed journals (over 300 reviews performed) in the area of heat transfer and energy engineering. He received an Outstanding Reviewer Certificate from the following journlas: Journal of Cleaner Production;  Applied Thermal Engineering Journal, Energy,  International Journal of Thermal Sciences, International Journal of Heat and Mass Transfer, Chemical Engineering and Processing – Process Intensification, International Journal of Electronics and Communication, Electrical Power and Energy Systems,. In 2019 he reviewed “Top reviewer” distinction form Publons for Engineering and Cross-Fields. Prof. Oclon is an Associate Editor of Journal of Cleaner Production (published by Elsevier), and Editor in Chief of Cleaner Engineering and Technology (published by Elsevier), Topic Editor of Energies (published by MDPI) and is a member of Editorial Board of ISI indexed Progress in Computational Fluid Dynamics, an international journal (published by Inderscience). He was also a Guest Editor of highly ranked heat transfer journlas including: Applied Thermal Engineering (Elsevier), Heat Transfer Engineering (Taylor & Francis), International Journal of Numerical Methods for Heat and Fluid Flow (Emerald), Energies (MDPI), Journal of Thermal Science (Springer).

Modeling of heat transfer in PVT based renewable energy system with underground energy storage

Paweł Ocłoń

Cracow University of Technology, Energy Department, Faculty of Environmental and Energy Engineering, Al. Jana Pawła II 37, 31-864, Krakow, Poland

RESHeat is an advanced renewable energy system for residential building heating and electricity production. RESHeat delivers an advanced 100% RES system on combined cooling, heating, and power (CCHP), including seasonal underground energy storage. The underground heat storage unit comprises of high-capacity water tanks being buried in the ground. The use of two water tanks is proposed the first on thermally insulated and the second one without insulation. The non-insulated tank (heat accumulator) is used to transfer heat from water to the ground and increase ground temperature, hence using this tank, it is possible to accumulate heat within the ground. The temperature in the non-insulated tank is up to 40oC, due to the utilization of waste heat from PV panels cooling. The insulated tank (hot water storage tank) is used as a thermal energy storage unit for domestic hot water heating. This tank is linked with evacuated-tube solar collectors with a sun-tracking system, and the water temperature up to 80oC can be achieved. A non-insulated underground thermal energy storage tank can be alternatively charged through solar collectors (only when the thermal energy excess exists in the insulated tank). The heat absorbed by the ground can be removed from the surface of the tank and carried away with the groundwater to another location. Therefore, the losses must be prevented by insulating the second domestic hot water tank. The insulated tank can also be used as a peak heat source during the winter period when the external temperature is very low. Also, in autumn and wintertime, when the output temperature from solar collectors is lower than 40oC the waste heat is used for ground regeneration through heat accumulators of borehole drillings.

The idea of the system is as follows: the waste heat form PV panels cooling is stored in the storage tanks buried underground. This allows increasing the ground temperature around the tank and restore the ground capability to deliver the heat after a heating period. In addition, PV panels will produce the electricity needed by the proposed system and also needed to cover the building heating demand. Due to the cooling of PV panels, electrical energy production efficiency is expected to be increased by 5-10%. The heat stored in the ground, and storage tanks will be used by the heat pump to deliver the heat for the building. Also, due to the application of a thermal energy storage system, the COP of the heat pump is increased. The value of average yearly COP higher than 5 is achieved. Therefore, less electrical energy is needed to run the compressor in the heat-pump cycle. The system will be fully renewable since the electrical energy delivered to the heat pump will be produced by PV panels. An additional novelty is the application of a sun-tracking system at PV panels to increase the amount of electrical energy produced over a day. Also, the solar collectors with a sun-tracking system are used to support the domestic (hot) water production during the spring-autumn period. Moreover, we propose to use the waste heat from the air-conditioning unit. Hot air after the condenser will be used to heat the domestic hot water by using a plate fin-and-tube heat exchanger. The heat can also be used to increase the temperature of the underground thermal energy storage system, and to prepare the domestic hot water (this will be an extension of the existing setup). Therefore, the overall efficiency of the system is expected to increase, as well as the ground heat pump output. In a hot climate, the modification can be used to heat up the domestic hot water, while in the temperate climate countries (Poland, Czech Republic, Germany) the heat pump output will be increased during the heating season. The ground should be insulated from the top.

The proposed system is a comprehensive solution, providing the customer with a ready-made system of heat supply to the building entirely based on RES. The system will be offered along with the necessary automation and control systems and will be maintenance-free for the end-user. In addition, the system will be autonomous as it produces the electricity needed to power the components. The primary energy demand of the building that will be equipped with a proposed energy system is zero, so the non-renewable primary energy demand indicator EP [kWh/(m2-y)] for the heat supply of buildings can be reduced to 0.  This Keynote Lecture presents a preliminary computation of the heat transfer processes occurring within the RESHeat system. The energy efficiency, and thermal energy storage is calculated for the period of one year. The research carried out in RESHeat project is funded from EU funds within the Horizon 2020 framework.

oclon

Terry Simon

Mechanical Engineering Department University of Minnesota 111 Church St. S.E. Minneapolis, USA

Professor Simon received Mechanical Engineering B.S., M.S. and Ph.D. degrees from Washington State University, University of California-Berkeley, and Stanford University. He has eight years of industrial experience followed by 39 years as a faculty member at the University of Minnesota. He is the Ernst R. G. Eckert Professor of Mechanical Engineering. His major research interests include experiments, computation, and visualization of heat, mass, and momentum transfer. He is a Fellow of the ASME and has served five-years as the Senior Technical Editor of the Journal of Heat Transfer, and is the 2020 Heat Transfer Division Memorial Award recipient. He was involved with the organization of many technical meetings and sessions including an International Heat Transfer, an ASME/JSME Thermal Engineering Conference, and an International Workshop on Heat Transfer. As a long-term member of the ASME Gas Turbine Heat Transfer Committee he served as Committee Vice-Chair and Chair and received the Outstanding Service Award. He is also an active member of the International Centre for Heat and Mass Transfer in which he is now President and serves on the Executive Committee.

Computing the Decay of Turbulence in Complex Flows

T. Simon and K. Nawathe, U of Minnesota

Predictions of turbulent transport in complex flows using Reynolds-Averaged-Navier-Stokes (RANS) closure models are not always sufficiently accurate. One possible reason has been attributed to excessively rapid dissipation of turbulence. Since turbulence levels affect pressure losses and heat and mass transport in flows, accurate predictions are essential in design applications. Gas turbine flows are such applications. Turbine passage flows experience considerable curvature and streamwise pressure change. Upstream of inlets to the turbines are combustors, which necessarily generate high-level, large-scale turbulence. To assess accuracy of prediction, computed and experimental results are compared. Measurements of turbulence intensities and length scales are presented in this presentation along with calculations of turbulent transport and dissipation of turbulence using industry-standard RANS models. The effects of combustor turbulence and vane passage geometry are documented. Conditions under which the models fail are documented. There is evidence that streamwise decay of turbulence in this setting is excessive. Although the study is performed on a specific geometry, the results are expected to be applicable to many complex flows accelerating in curved passages. The results will help modelers in assessing the performance of some design models.

simon

Dr. Hui Xu

Associate professor in the School of Aeronautics and Astronautics at Shanghai Jiao Tong University, China

Dr. Hui Xu is an associate professor in the School of Aeronautics and Astronautics at Shanghai Jiao Tong University, China and an honorary research fellow at Imperial College London, United Kingdom. Dr. Hui Xu’s research is centred around developing and deploying numerical approaches for efficiently modelling and understanding complex physical phenomena in fluid mechanics and related interdisciplinary fields.  Much of his work to date has focused on efficient applications of high-fidelity spectral/hp element methods in transitional flows and turbulence-resolving simulations and also on cross-validation of simulation and experimental data.

This talk will give a brief overview of the recent advances of high-fidelity numerical approaches and their applications in fluid mechanics. Understanding and analysing complex physical phenomena in fluid flows significantly depends on precisely solving the related governing equations, which offer the promise for reliable and accurate evaluation of scientific and engineering strategies in real applications. This talk will discuss the recent developments in enhancing stability and efficiency of high-fidelity large-scale simulations of complex flows. It will also show that introducing high-fidelity numerical approaches into applications areas not only benefits the area, but also provides return benefits on our understanding and implementations of these methods.

huixu

Edouard Walther

PhD, MSc and Agrégé in Civil Engineering

Edouard Walther works at AREP L’hypercube, SNCF’s in-house engineering & architecture consulting firm, where he is in charge of applied research in building physics. PhD, MSc and Agrégé in Civil Engineering, his topics are air quality, thermal comfort and numerical methods.

Comfort modelling in outdoor and semi-outdoor spaces

In this talk the methodology developped at AREP for the will be presented, from the occupants’ scale to the urban neighbourhood, using open-source codes for fluid mechanics, radiation and building simulation. The usage of metamodels will also be shown, allowing to lift the computational burden.

walther

Yeon Won Lee

Department of Mechanical Design Engineering Pukyong National University, Nam-gu, Busan, Korea

International Steering Committee, Asian Symposium on Visualization, 2013 ~ present

Co-Chairman of ICCHMT 2017, 10th Int’l Conference on Computational Heat, Mass and Momentum Transfer, 28 May – 1 June, 2017, Seoul, Korea

Co-Chairman of NCFE 2016, 9th National Congress on Fluids Engineering, 10-12 August, 2016, Daegu, Korea

Organizing Committee and Int’l Advisory Committee of ASCHT 2015, 5th Asian Symposium on Computational Heat Transfer and Fluid Flow, 22-25 November, 2015, Busan, Korea

Chairman of KSV 2015 Autumn Conference, Korean Society of Visualization, 4-5 December, 2015, Daegu, Korea

Chairman of ISAMPE 2014, Int’l Symposium on Advanced Mechanical and Power Engineering, 27-30 November, 2014, Busan, Korea

Organizing Committee of KSME 2013 Annual Meeting, Korean Society of Mechanical Engineers, 18-20 December, 2013, Gangwon land, Korea

Organizing Committee of AJWTF 2012, 4th Asian Joint Workshop on Thermophysics and Fluid Science, 14-17 October, 2012, Busan Korea

General Chair of ISAE 2011, Int’l Symposium on Advanced Engineering, 10-12 November, 2011, Busan Korea

Suppression of sloshing in horizontally excited tanks using air-trapping mechanism

Yeon Won Lee, Ph.D.

Sloshing is any motion of liquid free surface due to physical disturbances in a partially liquid filled cargo tank. Sloshing is an important phenomenon with wide industrial and practical applications. It is studied and analyzed in many fields – such as sea, land and air transport; civil, chemical, mechanical and nuclear fields. This talk mainly deals with the sloshing phenomena in ocean industries.

Since sloshing phenomenon is highly non-linear, discontinuous, inhomogeneous, and three-dimensional, violent sloshing creates high impact forces in the tank, which can create structural and stability problems, eventually leading to failure of the system. Employment of baffles is a common method to suppress sloshing in the tank because baffles can supply a kind of passive control on the effects of liquid motion. However, employment of baffles alone is insufficient to control sloshing effects in a tank. Various factors – such as tank geometry, tank excitation, filling level, types and placement of baffles etc. – come into play. To address these issues, many classification societies provide guidelines to assess sloshing loads and safety design.

The assessment of sloshing loads or investigating the effects of baffles in a container is usually carried out based on theoretical, laboratory experimentation and numerical approaches. In the recent past, numerical analysis of sloshing has gained momentum due to advances in computational techniques. The literature cites different methods to analyze sloshing phenomena in the tank using various kinds and placements of baffles and methods within the numerical framework. However, suppression of sloshing in a tank using the ‘Air-trapping mechanism’ is rare or first of its kind in the industry. The air-trapping mechanism can be termed as trapped air in between the baffles, which play a crucial role in reduction of sloshing impact on the tank walls and corners.

This presentation talks about the numerical techniques used to analyze the sloshing behavior in the tank. The geometry and excitation frequency effects, sloshing flow behavior for various Reynolds numbers and the effects of air-trapping mechanism on the sloshing phenomena in a membrane type tank are discussed. This kind of study using numerical techniques will enhance our understanding of sloshing phenomena and its suppression and can lead to implementation and design changes in membrane type tanks for cargo carriers.

won