Research On Dynamic Optimization Of Chemical Engineering

Optimization technology is widely applied to production process. It becomes the focus of various industries. Dynamic optimization technology of chemical process is very important for operation process design, production capability, price predominance, especially for increasingly important economizing energy sources and reducing consume. The dynamic optimization problems of chemical process are mainly researched in this thesis aimed at the current status quo.For optimization algorithm, deeply research and framework analysis about simulated annealing algorithm are in this thesis. The Corana?ˉs method which controls the neighborhood range is very useful since the method could automatically determines the neighborhood range, but the performance of the method in terms of the search ability is not good for multivariable optimization problems. It always falls the local optimum. The performance of Corana?ˉs method is investigated in this paper, and the reason why couldn?ˉt find the optimum is analyzed also. Then advance a new scheme for adjusting the neighborhood range in continuous optimization problems to obtain good solutions in shorter annealing steps. The simulated annealing algorithm, Corana?ˉs method and improved algorithm are compared by some examples with the same parameters. The results are showed that the improved method has higher precision and efficiency for multivariable optimization problems than foregoing methods.Because the chemical process has non-linear and non-steady-states characteristics, so its optimization problem actually is differential-algebraic optimization problem. Analytics always couldn?ˉt solve this kind of dynamic optimization problem. At the present time, numerical technique is the common method. It transforms the differential equations into algebraic equations, makes up of simultaneous equations with the other algebraic equations. So it becomes commonly optimization problems of discrete system. Orthogonal collocation on finite elements has many merits such as high precision and high efficiency. It can discrete the differential equations, and simulate the process by joining the other algebraic equations. Feasible direction method is widely applied to solve...