Broader Applications of Process Systems Engineering
Masoud Soroush
Professor, Drexel University
An overview of our current research activities is first presented. Our contributions in a
couple of the projects, dynamic modeling and control of solid oxide fuel cells, state and
parameter estimation via Bayesian belief networks, understanding kinetics of
polymerization reactions using computational quantum chemistry, and early detection of
seizure in patients with epilepsy are described.
The rest of the talk will be spent on presenting our work on dynamic mathematical
modeling and analysis, and control of a tubular solid oxide fuel cell system. A dynamic
compartmental model based on first principles is presented. The model accounts for
diffusion processes, inherent impedance, transport (heat and mass transfer) processes,
electrochemical processes, anode and cathode activation polarizations, and internal
reforming/shifting reactions, among others. Dynamic outlet voltage, current and fuelcell-tube temperature responses of the cell to step changes in external load resistance and
conditions of feed streams are presented. Simulation results show that the temperature
and pressure of the inlet air stream and the temperature of the inlet fuel stream strongly
affect the dynamics of the fuel cell system. They also indicate that temperature of the
inlet air stream has the strongest effect on the cell performance, and effects of the inlet air
and fuel velocities on the cell response are weaker than those of inlet feed pressures and
temperatures. A simple control system is then implemented to control the fuel cell outlet
voltage and cell-tube temperature through manipulating the pressure and temperature of
the inlet air stream, respectively. The results show that the control system can
successfully reject unmeasured step changes (disturbances) in the load resistance, the
velocity of the inlet air stream, and the pressure, temperature and velocity of the inlet fuel
stream.