CENTER OF ENERGY AND FLUID MECHANICS
Description of the Research Center
The Center of Energy and Fluid Mechanics is a research center hosted by IDMEC and the Department of Mechanical Engineering of Instituto Superior Técnico, University of Lisbon. The members of this Research Center have been engaged in both fundamental and applied research in several energy related topics for more than 20 years. The research covers a broad range of fundamental topics directly related to energy such heat transfer, turbulence physics and modeling, computational fluid dynamics, and experimental fluid mechanics, and also specific energy application topics such as energy efficiency, renewable energy, hydrogen and fuel cells, clean combustion, energy and environment in transports and turbomachinery. Presently the Center is composed of around 20 senior researchers plus around 30 PhD and Msc students, and this number has been stable and is expected to remain so in the future. The fundamental research carried out in the Research Center during the last few years includes: investigation of the turbulent/radiation interaction for non-reacting and reacting flows, developments of hybrid methods for the solution of the radiative transfer equation; investigation of the turbulent entrainment in free shear flows, study of viscoelastic turbulence dynamics, development of mathematical and computational tools to study uncertainty in reactive flows, study of forest fire propagation, characterization of isothermal microflows of biological and non-biological fluids and flameless and oxy-fuel combustion.
The applied research carried out in the Center during the last few years includes: investigation of co-combustion of coal with biomass, study of the formation of fine particulate matter in biomass combustion; development of design tools for air turbines for wave energy conversion and for small cross-flow hydraulic turbines; development of ocean wave energy utilization, development and promotion of tools and practices for energy management, urban planning and new and renewable energy technologies, development of tools to assess the potential for renewable energy technologies in developing countries and remote regions; development region’s environmental indicators for the road transport sector, and examination of the algal industrial biorefineries viability and sustainability. The Research Center has various computational and experimental laboratories, occupying a total area of around 300 m2, which is largely well equipped with commercial equipment and instrumentation but also with a significant amount of in-house computational tools/codes, and designed test sections, including a large-scale furnace which is able to fire either gaseous, liquid and solid fuels, including biofuels.
During the last five years (2009-2013) the Research Center published around 150 articles in peer reviewed international journals and various researchers of the Center received national and international awards for their scientific achievements. Most of the researchers of the Center have strong links with the international research community in terms of collaborative research work. The research activities during the last few years have been funded by i) the national science foundation (FCT), ii) the European Union, iii) government and public institutions, and iv) private companies (national and international).
Structure of the Research Center
The Center of Energy and Fluid Mechanics has six main scientific groups as follows:
Combustion and Sustainable Development
Coordinator: Professor Mário Costa
The research of the Combustion and Sustainable Development group aims at: (i) investigation on particle ignition, combustion kinetics and fragmentation, and ash behavior of biomass fuels; (ii) investigation on co-combustion of coal with biomass; (iii) investigation on flameless oxidation and oxy-fuel combustion phenomena; (iv) development of a novel hybrid engine concept for future aircraft propulsion systems; (v) study of biomass gasification and pyrolysis processes; (vi) development and promotion of tools and good practices for energy management, urban planning, rational use of energy and integration of renewable energy technologies; (vii) identification and assessment of energy efficiency and renewable energies opportunities, initiatives and projects with the purpose of promoting energy sustainability and greenhouse gas emission reduction; (viii) identification and dissemination of good practices examples to overcome political barriers, increase environmental awareness and market stimulation; and (ix) investigation of barriers, drivers and pathways to individual and collective prosumer participation in social energy markets and the democratization of energy.
Energy in Transports
Coordinator: Professor Tiago Farias
The Energy in Transports group aims at developing research activities in the fields of sustainable mobility, alternative fuel vehicles, vehicle dynamics and environmental performance and alternative and sustainable energies within the transport industry. In more detail, the research areas currently covered are: quantification of impacts in a life-cycle analysis of different vehicle technologies and alternative energy pathways; real time monitoring of dynamic, energy and emissions characteristics of vehicles and individuals; the study of electric solutions for urban mobility; urban logistics; users’ behavior analysis; and urban accessibility and exposure assessment. Throughout the past 10 years the group has published more than 200 papers in Scientific Journals, International Books and International Conference Proceedings. The group has also participated in several European projects, and has considerable involvement of industry partners. In addition, it has established solid research partnerships with well recognized international institutions, namely MIT, CMU, University of Florida, North Carolina State University as well as national institutions and research laboratories.
Currently the group comprises 1 principal investigator, 5 post docs, 7 Phd students, and several chemist, environmental and mechanical engineers
Flow Physics and Simulation
Coordinator: Professor José Carlos Pereira
The Flow Physics and Simulation group aims at: (i) understand and model turbulent entrainment across fluid interfaces, (ii) study the effects of polymer additives in turbulent flows, (iii) develop subgrid-scale models for scalars and for turbulent flows with polymer additives, (iv) study non-equilibrium turbulence, (v) develop mathematical and computational tools for uncertainty quantification in reactive, hemodynamic and forest fire propagation flows, (vi) study instabilities and transition in aerodynamics, (vii) develop low-Reynolds-number flow concepts for passive stall control and pulsed propulsion in micro-aerial-vehicles, (viii) develop new computational tools for complex geometry and multiphase flows with SPH methods.
Coordinator: Professor Pedro Coelho
The research of the Heat Transfer group aims at: (i) development of computational methods for the solution of radiative transfer in participating media, with special emphasis on the discrete ordinates, finite volume and hybrid methods aiming at an improvement of the accuracy and computational effciency of the calculations; (ii) application of state-of-the-art models for the calculation of radiative properties of gases and particles in the solution methods for radiative transfer problems; (iii) investigation of the interaction between turbulence and radiation in turbulent reactive flows; (iv) application of the developed methods to the numerical simulation of turbulent reactive flows; (v) development of classical and multi-scale methods for the solution of transient radiative transfer problems; (vi) simulation of the interaction between a thermal plume and the ceiling jets induced by impulse fans, with or without a heat source, aiming at the investigation of fire safety in underground car parks.
Microfluidics and Biomicrofluidics
Coordinator: Professor Viriato Semião
The research of the Microfluidics and Biomicrofluidics group aims at: (i) development of numerical techniques, particularly lattice Boltzmann, to simulate both isothermal and non-isothermal flows inside stationary and rotating (with body force) devices, (ii) laboratory experimentation on non-biological fluid flows inside microdevices, and (iii) in vitro experimentation on blood flows inside microdevices.
Research and development on non-biological fluid flows inside microdevices focus on new and innovative techniques to dynamically characterize steady and unsteady regimes at both stationary and rotating frames, and for both Newtonian and non-Newtonian fluids. In 2008 the group developed a new microvisualization technique, based on digital image processing and mathematical curve matching, to characterize kinematically the advance of the liquid interfaces inside stationary microdevices. In 2013 the group, in association with Biosurfit, developed a technique to use micro-PIV to characterize flows in rotating microdevices.
As for biological fluids, blood of different animals has been used to characterize its flows inside microdevices in terms of thrombus formation, hemolysis, plasma-layer building up at solid boundaries, erythrocytes organization in different flows, erythrocytes deformation and blood viscosity. All these issues are relevant in blood oxygenation processes, particularly those using biocompatible membranes. The group has partnerships and collaborations with: ICEMS (Profª Norberta Pinho e Prof. Vítor Geraldes); Biosurfit; Probiológica; Faculdade de Medicina Veterinária.
Renewable Energy Technologies
Coordinator: Professor Luis Gato
The Renewable Energy Technologies group has been active for more than thirty years, especially in ocean wave energy conversion and in turbines for small hydroelectric plants. More recently, the group has been involved also in the development of small wind turbines.
Most of the work focussed on wave energy conversion, in which the group achieved high international recognition. A high landmark was the overall coordination of the four European projects that funded the basic studies, design, construction and monitoring of the European wave energy pilot plant at the island of Pico, Azores. This plant, still operational, was the first wave energy plant worldwide designed to permanently supply electrical energy to a grid. The activity and expertise of the group covers most areas in wave energy technology. Strong points are hydrodynamics, numerical modelling, model testing, power take-off equipment, especially air turbines, plant control and moorings. In the last few years, the activity focussed on offshore wave energy converters of oscillating water column type and on the development of new types of air turbines. The group is playing a key role in the coordination and teaching of the one-semester specialization on Ocean Renewable Energy at IST, within the framework of the EUREC master course in Renewable Energy.
The group has also been involved in the numerical and experimental development of small hydraulic turbines, especially of cross-flow and Kaplan-bulb types.
Main Achievements of the Research Center
In terms of scientific indicators the overall research achievements of the Research Center during the period 2008/2012 were the following: publications in international journals with peer review (143), publications presented in international conferences (225), publications in national conferences (27), PhD theses completed (36) and MSc theses completed (146).
In terms of research and development work the main achievements of the Research Center during the period 2008/2012 were the following:
In the area of heat transfer: i) development of hybrid finite volume/finite element method and evaluation of the accuracy (using bilinear and spherical triangular basis functions) of radiative transfer computations; ii) development of a theoretical analysis of the influence of turbulence on radiative emission in turbulent diffusion flames; iii) development of a computer code based on OpenFoam for the large eddy simulation of turbulent heated jets.
In the area of turbulence physics and modeling: i) characterization of the turbulent entrainment mechanism in free shear flows (including the subgrid-scale modeling), ii) development/validation of new modeling strategies for large-eddy simulation (including turbulent-radiation interaction in simulations of turbulent heated jets). In the area of new computational paradigms and CFD: i) robust and accurate modelling of reactive flows in inert porous media, ii) development of new refinement criteria strategies with the purpose of application to multiscale problems.
In the area of modelling and experimental fluid mechanics: i) modelling and measurement of dispersion and deposition of dry-powder aerosols, including the development of a particle-based computational methodology; ii) production and optimization of the aerodynamic characteristics of particles for inhalation; iii) demonstration of low-Reynolds-number flow concepts for passive stall control and pulsed propulsion in micro-aerial-vehicles. In the area of microfluidics: i) establishment of a laboratory; ii) advances on several steady and unsteady microflows for both Newtonian and non-newtonian fluids, including blood; iii) computational work with Lattice-Boltzmann body-force models for rotating flows developed.
In the area of renewable energy: geometry optimization and model testing of a new patented geometry for spar-buoy OWC wave energy converter; non-linear modelling of moorings for arrays of floating wave energy converters. In the area of fuel cells/hydrogen energy: i) preparation of a Redox 10 W reversible battery; ii) establishment of a procedure to prepare the electrolyte.
In the area of combustion: i) successful application of the eddy dissipation concept and the transport pdf method to the simulation of combustors operating in the flameless regime; ii) advances in the understanding of the flameless and oxy-fuel combustion modes; iii) quantification of the particulate matter inside a domestic biomass-fired boiler and evaluation of the fundaments of particulate matter formation.
In the area of energy and environment in transports: i) ability to simulate the energy consumption of vehicles equipped with battery or with a ultracapacitor or with a combination of both; ii) ability to optimize a powertrain configuration combined with the energy management strategy for a specific probable driving profile; iii) development of methodologies to evaluate driver behavior based on collected speed profiles; iv) development of a laboratory to monitor hybrid and electric vehicles; v) development of and pedestrian mobility laboratory. In the area of turbomachinery: i) a 15 kW impulse-type self-rectifying air turbine with controlled guide vanes was built and tested on a floating OWC wave energy prototype in Galway Bay, Ireland; ii) model of a novel patented bi-radial air turbine.