TY  - JOUR
AU  - Caspari, Adrian
AU  - Lüken, Lukas
AU  - Schäfer, Pascal
AU  - Vaupel, Yannic
AU  - Mhamdi, Adel
AU  - Biegler, Lorenz T.
AU  - Mitsos, Alexander
TI  - Dynamic optimization with complementarity constraints: Smoothing for direct shooting
JO  - Computers & chemical engineering
VL  - 139
SN  - 0098-1354
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - FZJ-2020-02205
SP  - 106891 -
PY  - 2020
AB  - We consider optimization of differential-algebraic equations (DAEs) with complementarity constraints (CCs) of algebraic state pairs. Formulating the CCs as smoothed nonlinear complementarity problem (NCP) functions leads to a smooth DAE, allowing for the solution in direct shooting. We provide sufficient conditions for well-posedness. Thus, we can prove that with the smoothing parameter going to zero, the solution of the optimization problem with smoothed DAE converges to the solution of the original optimization problem. Four case studies demonstrate the applicability and performance of our approach: (i) optimal loading of an overflow weir buffer tank, (ii) batch vaporization setpoint tracking, (iii) operation of a tank cascade, and (iv) optimal start-up of a rectification column. The numerical results suggest that the presented approach scales favorably: the computational time for solution of the tank cascade problem scales not worse than quadratically with the number of tanks and does not scale with the control grid.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000555543100008
DO  - DOI:10.1016/j.compchemeng.2020.106891
UR  - https://juser.fz-juelich.de/record/877452
ER  -