Energy Conversion and Systems

We carry out modelling and experimental research for developing more efficient biomass and biofuel conversion processes. We study optimal fuel production pathways and efficient ways to transform their chemical energy to power and heat. We work on black liquor combustion and spraying in recovery boilers, CFB combustion and gasification of waste and simulation and optimisation of modern bio-based power plants.

We work on transport biofuels conversion processes in engines i.e. new combustion systems like dual-fuel combustion, gas diesel combustion and other new combustion regimes. We also study new advanced conversion processes such as super-critical water gasification and hydrothermal treatment of very wet biomasses without needing to dry them first, increasing energy efficiency.

Key personnel

• Professor Mika Järvinen
• Professor Martti Larmi
• Senior University Lecturer Tuomas Paloposki

Our key technologies in experiments are optical diagnostics of combustion and flow in furnaces and engines and related technologies, e.g. sprays. We have laser equipment for PIV, LIF and PDA and equipment for filtering, analysing and digitally processing the optical signal. We have optical spray bombs and a fully optical high speed engine for especially engine combustion research. We have special equipment and expertise for recovery boiler experimental research.

Key personnel

• Professor Martti Larmi
• Professor Mika Järvinen
• Senior University Lecturer Tuomas Paloposki
• Senior Engineer Kari Saari

Modern energy systems research focuses on finding optimal solutions for ensuring a comfortable and healthy indoor environment while minimising energy use. This is achieved both by utilising computer simulation and optimisation and by conducting experimental research on novel technologies.

Energy systems of buildings are studied both experimentally and with the help of simulation and optimisation. The main focus areas are building energy efficiency and its optimisation, energy solutions for low-energy buildings and indoor air quality & thermal conditions.

Energy systems research is also studied at the community level by applying simulation, optimisation and system analysis tools. In densely populated areas, balancing the production and usage of energy over multiple buildings is more beneficial than concentrating on individual buildings. Research includes the development optimal strategies for energy efficiency, environmental impact and economics.

Building energy efficiency is studied by utilising building simulation tools such as IDA ICE and TRNSYS in conjunction with single- or multi-objective optimisation methods, e.g. genetic algorithms. Energy solutions for low-energy buildings are associated with passive or zero-energy buildings. Such buildings and their energy systems are studied in a five-year research project funded by the Academy of Finland, both with the computational methods mentioned earlier and with a semi-empirical nearly zero-energy building emulator located in the research group’s laboratory.

Acceptable air quality and thermal conditions are important in maintaining healthy indoor environments. These are influenced by both the HVAC systems of the building and by the building itself. Thermal environment is researched through CFD simulations and by performing measurements in an HVAC test chamber located in the research group’s laboratory. Special equipment, such as a custom thermal manikin and a multi-gas analyser, are used in the measurements.

Multi-objective optimisation tool – MOBO

In collaboration with VTT, the research group has developed a multi-objective optimisation tool called MOBO. MOBO can be coupled with virtually any (simulation) program producing the objective function values. MOBO was initially designed for building performance optimisation, but it can also be used for many other applications. The user can give discrete or continuous variables, make algebraic formulas of optimisation parameters and set constraints. MOBO features several different optimisation algorithms, including evolutionary, deterministic, hybrid, exhaustive and random algorithms. The user is advised to read the manual that comes with the MOBO installation.

In order to download MOBO and/or its source code, please participate in this survey and fill in your contact details to receive a download link.

Key personnel

• Professor Risto Kosonen
• Professor Risto Lahdelma
• Professor Kai Siren
• Professor Sanna Syri
• Professor Markku Virtanen

In energy technology for industry, the main research areas are energy- and material-efficient technologies, process concepts and process integration. Research in energy- and material-efficient technologies covers industrial drying processes and integrated trigeneration of heat, power and cooling.

Experimental research concentrates on drying technology. The research group’s laboratory is equipped with three different dryers: a vacuum contact dryer for drying different types of veneers and other materials; a drum dryer for drying biomass and other solid materials; and a rotary vacuum evaporator to evaporate various materials.

Energy- and material-efficient production technologies and concepts are also studied with the aim of improving the efficiency of industrial sites through process integration. This research includes the development of novel computational tools and measurement approaches for overall efficiency to ensure that multiple aspects of efficiency are accounted for.

Key personnel

• Staff Scientist Timo Laukkanen
• Senior University Lecturer Henrik Holmberg
• Professor Risto Lahdelma
• Professor Sanna Syri
• Senior University Lecturer Jukka Paatero

The computational team, headed by Professor Ville Vuorinen, focuses primarily on high-performance CFD of turbulent flows, including large eddy simulation (LES) and combined LES-RANS approaches using various software such as open-source code OpenFOAM as well as commercial codes STAR-CCM+ and STAR-CD. The research has three primary directions: 1) chemically reacting flow (combustion), 2) heat transfer and fluid flows and 3) applications in manufacturing processes, including material science and machines with moving/rotating parts. The research of the team has broad industrial relevance for e.g. power plants, engines, boilers, combustion, electronics and chemical engineering.

Key personnel

• Professor Ville Vuorinen
• Senior Research Fellow Ossi Kaario
• Professor Mika Järvinen
• Professor Martti Larmi

We develop and study experimentally new composite phase change materials. The major goal is to invent an efficient and affordable material for seasonal thermal storage application.

We also exploit scale dependent thermal effects in order to develop improved thermal insulation materials and novel heat transfer fluids. The research consists of simulation and modelling of thermal radiation and conduction in micro- and nanostructured materials, preparation and measurements of nanofluids (fluids with suspended nanoscale particles in a base fluid) for enhanced convective heat transfer.

Key personnel

• Senior Scientist Ari Seppälä
• Professor Ville Vuorinen
• Senior Engineer Kari Saari