Research On VV&A System Of Distillation Column System

With the development of industrial intelligence,the application field of chemical process system simulation model is more and more extensive.It is not only used for scene reproduction and off-line training,but also has been applied in many fields,such as education and training,engineering design,auxiliary production and auxiliary research.At the same time,these applications put forward higher requirements for the reliability of the simulation model under various operating conditions.Whether the reliability of the simulation system meets the requirements of the system is directly related to the value of the simulation.Therefore,it is necessary to check,verify and confirm(Verification,Validation,Accreditation)the large and complex simulation system or simulation model,and which has become an essential part of the simulation work.Domestic and foreign scholars have put forward a lot of methods to validate the simulation model.However,some of the existing model validation methods rely on subjective experience,expert system,or statistical testing.But for the simulation system based on deep mechanism,the existing methods are difficult to effectively and comprehensively test because of various input forms and changeable outputs under a variety of conditions.In order to solve the problem,this paper mainly focuses on the chemical process system simulation model based on the mechanism modeling.The SDG model is used as the verification model,the VV&A system is used to validate the model and the reliability of the model is evaluated.Firstly,according to underlying mechanism of simulation model,understand the causal relationship between variables of the model and use the model’ key variables that needs to be verified and tested as nodes of SDG model,analyst and confirm the qualitative and quantitative relationship between variables,then establish the SDG verification model.Secondly,a new VV&A verification system is proposed,which is multi-level test case methods.Multi-level test case method is divided into three types,three levels,from qualitative to quantitative,not only covered the chemical process open parking operation and steady state verification,but also included abnormal conditions and equipment failure verification.Thirdly,SDG verification model is analyzed,and test cases are built for the system simulation model by the method of multi-level test cases method.Finally,according to SDG verification model and multi-level test case method,methacrylate-methanol-water distillation simulation model was used as an example.The simulation software of VV&A verification system is carried out in the VS2010 development platform with C++ language.The simulation software can not only test the reliability of the simulation model,but also evaluate the reliability of the model.Multi-level test cases are combined with qualitative and quantitative methods to conduct a comprehensive verification and evaluation for the process of chemical process system simulation model in the process of opening,stopping and steady state and faulty mode.Through the comparison of the experimental data,it is proved that to use SDG model is as verification model,the reliability and validity of the model are effectively and comprehensively evaluated by the multi-level test cases.