Research On Modeling And Simulation Of Petrochemical Multi-level Material Flow Model Based On DEVS

Based on computer technology, communication technology, and automation technology, Computer Integrated Manufacturing System (CIMS) in Process Industry is an integrated automation system consisting of process control and enterprise management. It makes the enterprise more effective and competitive. Modeling and simulation technologies play crucial roles in the application research of CIMS. Traditional modeling and simulation usually focus on the demand of a certain level (PCS/MES/ERP) of CIMS, so model inconsistency makes information integration and application module development difficult. Multi-Resolution Modeling (MRM) is the mainstream method for integrated modeling. Based on Multiple Resolution Entity (MRE), this thesis built a petrochemical multi-level material flow model using a hierarchical modeling approach based on DEVS, and developed a petrochemical multi-level material flow simulation platform. The system can simulate the petrochemical material flow process under the effect of production events on different levels of CIMS. And inconsistency between multi-level simulation models is naturally avoided due to closure under composition of DEVS. The main works are as follows:1. According to the relation between DEVS and MRE, a hierarchical modeling approach is proposed: First, enterprise material flow models on the bottom of production process are built with DEVS. Then multi-level enterprise material flow models could be got by temporal and spatial aggregation. It can realize material model reuse and solve the problem of model inconsistency.2. On the basis of quasi-steady-state linear mass balance model,according to ISA-95 and the demand of planning, scheduling and controlling of CIMS, the theory about the petrochemical multi-level material flow model architecture is improved.3. A petrochemical multi-level material flow simulation model is built by the hierarchical modeling approach based on DEVS. Considering the model driven by production events, temporal and spatial decomposition of production events is discussed. And verification of model consistency between different level models is proposed for the petrochemical multi-level material flow model.4. Based on DEVS simulation tool CD++*, we design and realized a petrochemical multi-level material flow simulation platform. It can simulate the petrochemical material flow process under the effect of production events on different levels of CIMS.5. Implementation of the petrochemical multi-level material flow simulation platform is introduced according to the information of one refinery, and effectiveness of the platform is verified.This thesis concludes with a summary and prospects of future work.