Research

Mail to:
Department of chemistry, Norwegian University of Science and Technology, Realfagbygget, D3, NO-7491 Trondheim, Norway
Telephone/fax: +47 73594179 / 47 73550788
Email: signe.kjelstrup@nt.ntnu.no

My main research field is transport theory and energy optimization. I am interested in understanding interacting fluxes of heat, mass and charge, and chemical reactions, and how energy can be converted in the most efficient way in industrial systems. I am currently writing a book on Nonequilibrium Thermodynamics for transport in systems where the surface plays an important role.
Examples of such systems are electrode surfaces in electrochemical cells, membrane surfaces in separation technology and liquid/wapour surfaces for instance in distillation. Simulations are used to investigate the nature of the lost work in the irreversible processes.

A three-dimensional snapshot of gas/liquids particles in a temperature gradient of 10exp8 K/m. Coefficients of transport and entropy production rates are of interest.

New theories are derived and I am very interested in their practical applications; for instance in fuel cells (cf. Anne-Kristine Meland), (cf. Preben J.S. Vie), phase transitions (see snapshot above), distillation (cf. Audun Røsjorde and ) reactor modelling (cf. Lars Nummedal), and (cf. Eivind Johannessen) and the environmental effects of industrial activity (cf. Anita Zvolinschi) Industrial ecology.

Student projects in my group are related for instance to these activities.

Contents:: Fuel Cells; Energy Efficient Processes; High Temperature Systems; Post Doctoral Fellows, Guests; Doctor Students; Short CV and Publications Last Years

Fuel Cells

We collaborate with groups in Finnland, Denmark, and Sweden on fuel cell membrane studies and developments. Our fuel cell test station makes us attractive for collaboration. We have also long term contacts to Tsukuba Science Center in Japan, and to Los Alamos, National laboratory, USA.

Fuelcells
Schematic picture of the fuel cell.
Protons transport charge across the membrane and react with oxygen to form water

Transport
Our small laboratory cell can make a lego train move!

Temperaturprofil
The thesis of Preben J.S. Vie (May 2002) documented a that the single cell operates at non-isothermal conditions. Here is the temperature as function of position and current density.

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Energy Efficient Processes: The aim of this research is to find the path of a process that produces a given amount of product with the minimum energy cost. We study reactors that use natural gas as a reactant, and hydrogen producing reactors. Hydrogen is necessary for fuel cells. We have specified ideal boundary conditions for heat exchangers and designed operating lines for distillation columns.
The result of our optimization is that column heating should be performed in a different way than conventionally.
Typical example of equations that need be solved: eksempel.pdf

Here is the summary and introduction, taken from two of our articles: homeapplic.pdf, hometeori.pdf.

Here is the group working on energy efficient process design on the Onsager workshop in Leiden, 2000. From left to right: Erik Sauar, Lars Nummedal, Dick Bedeaux, Signe Kjelstrup, Eivind Johannessen, Audun Røsjorde, Gelein de Koeijer.

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High Temperature Systems: Studies of thermogalvanic cells are interesting both from a theoretical and a practical stand point. We have over the years studied the description of thermocells, in particular the transported entropy in these cells. In electrolysis cells, thermoelectric effects may lead to local heating or cooling of electrode regions. This can be seen from the figure below. When electric current is passing a cell with two aluminium electrodes, the temperature rises in the cathode, and decreases in the anode, porportional to the current used. This knowlegde may have a bearing on thermal modelling of electrolysis cells.

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Guests, Post Doctoral Fellows: Dr. Jianchu Qian, China 1998/99
Dr. Perumal Pugazhendi, India, 1999
Ass.prof. Dr. Monica Costea, Romania, 2000
Prof. Dr. Torben Smith Sørensen, Denmark, 2000
Dr. Mikael Paronen, Finnland, 2000-2002
Prof. Dr. C. Jesudason, Malaysia, 2001
Prof. Dr. M. Rubi, Spain, 2001

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Doctor Students

Recent Ph.D's Graduated from the Group: Magnar Ottøy; Steffen Møller-Holst; Belinda Flem; Erik Sauar; Ellen Marie Hansen; Lars Nummedal; Preben J.S. Vie; Gelein de Koeijer; Audun Røsjorde

Ph.D's in Progress

Short CV and Publications Last Years

Short CV, Signe Kjelstrup, professor dr.techn. et dr.ing., group leader
The Nansen foundation award for young scientists, 1980,
Honorary professor University of North East China, Shenyang, 1997
Invited guest professor to Kyoto University, Dept. of Fundamental Energy Science, 2000
Editorial Board of J. Non-Equilibrium Thermodynamics, Energy - The International Journal, and J. Applied Thermodynamics"
Board member Int. Soc. Applied Thermodynamics, Advisory board for ECOS since 1999.
Referee to Acta Chem. Scand., J. Phys. Chem., J. Non-Equilibrium Thermodyn., J. Electrochem. Soc., Electrochim. Acta, etc.

Publications in Referred Journals since 1996

My last publications can be found in the university library file FORSKDOC

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