Modelling and parameter identification for a two-stage fractional dynamical system in microbial batch process

Chongyang Liu, Xiaopeng Yi, Yanli Feng
2022 Nonlinear Analysis: Modelling and Control  
In this paper, we consider mathematical modelling and parameter identification problem in bioconversion of glycerol to 1,3-propanediol by Klebsiella pneumoniae. In view of the dynamic behavior with memory and heredity and experimental results in batch culture, a two-stage fractional dynamical system with unknown fractional orders and unknown kinetic parameters is proposed to describe the fermentation process. For this system, some important properties of the solution are discussed. Then, taking
more » ... the weighted least-squares error between the computational values and the experimental data as the performance index, a parameter identification model subject to continuous state inequality constraints is presented. An exact penalty method is introduced to transform the parameter identification problem into the one only with box constraints. On this basis, we develop a parallel Particle Swarm Optimization algorithm to find the optimal fractional orders and kinetic parameters. Finally, numerical results show that the model can reasonably describe the batch fermentation process, as well as the effectiveness of the developed algorithm. Keywords: fractional dynamical system, parameter identification, parallel optimization,
doi:10.15388/namc.2022.27.26234 doaj:b073cb9778c54cce9ec21c5a18a32caf fatcat:cyzbl4a7ivgbtgv3pxs3lauobe