Study On Nonlinear Modeling And Control Of Batch Dyeing Process

The fabric color online measurement and control technology in batch dyeingprocess is a major problem of dyeing and finishing industry. At present, dyeing andfinishing enterprises commonly achieve the purpose of controlling the dyeing qualityby improving the dyeing process, and detect the results of the fabric dyeing. Thismethod not only extends the fabric dyeing cycle, but also creates difficulty incontrolling the real-time problems during the dyeing process. Therefore, to study onnonlinear modeling and control of batch dyeing process has an extremely importantsignificance, as the research can improve quality problems such as color difference,paint stain and the poor level dyeing property of the fabric, improve the low pass ratereduce production costs and resource consumption.In the thesis, Reactive dye dyeing cotton fabric was chosen as the research object,and the main content of the study are as follows:1. Problems of conventional simultaneous determination are analyzed, using thefunction fitting method; an improved simultaneous determination method is proposedbased on the Lambert-Beer law to determine individual dye concentrations in themixed reactive dye liquors. The application of this method can overcome thedisadvantages of the conventional method. Meanwhile the measurement of theconcentration of each component is accurately improved.2. On the basis of in-depth analysis of the dyeing mechanism, the fixing chemicalreactions between dyes and fibers were simplified tantamount to one order serialreaction. Ultimately a chemical reaction kinetics nonlinear model was derived byusing the physical chemistry theory. We corrected the model to achieve linearexhaustion of the reactive dyes through the use of the inverse system control theory.At last the results show that the method can not only raise the level dyeing propertyof the fabric, but also improve the equilibrium dyeing rate of the dyes.3. Analysis the influence of dye accelerant inorganic salts in the dyeing process,using the methods of Neutralization titration experiment to get the additional data of inorganic salts, and fit the nonlinear expression of inorganic salts specific. At lastexperiment result proved that this method can improve the levelness of fabrics.4. The control of a single dye process was extended to mixed dye process; thespecific implementations of mixed dye dyeing process control was put forward basedon actual dyeing workshop.5. According to research achievement scored by dye workers and the dyeing theoryexperts and combined with the actual dyeing process, the batch dyeing online colormeasurement system was developed. The system host computer software, hardwareselection, and the overall layout were elaborated in detail.