Study On The Online Measurement System In The Gas-liquid Two Phase Flow Based On VC++

In the field of chemical, petroleum, pharmaceutical, nuclear power, metallurgyand other areas, gas-liquid two-phase flow is widely used. In order to actualize theautomatic, fast and accurate measurement of gas-liquid two-phase flow in industry,and achieve the requirements of safe, efficient and economic. The onlinemeasurement of Gas-liquid two-phase flow has become argent problem of industrial.Because of the complexity and randomness, it is necessary to study the flowmechanism, mathematical model and achieve the process control and detection withthe on-line measurement of gas-liquid two-phase flow.This paper is based on the principle of virtual binocular stereo vision, and thevisualization application in two-phase flow measurement as the background, theimage processing algorithm and the target detection algorithm are studied. Accordingto the stability of the gas liquid two phase flow measurement, optimize the imageprocessing algorithm; According to the velocity of the on-line detection to optimizethe connected component labeling algorithm. Eventually according to the principle ofvisualization complete the software GUI is designed. With the optimization ofalgorithm complete the software design and preliminary development. In the researchof this paper, The details are as follows:The method of high-speed photography of the two phase flow detection issummarized. The key problem in the gas-liquid two phase flow measurement softwareis studied base on the system structure and technical characteristics.The characteristics of image noise are studied, Comparative analysis of spatialdomain and frequency domain de-noising. According to the characteristics of the gasliquid two phase flow image noise, the wavelet threshold de-noising method isdesigned. The experiment results show that the wavelet threshold de-noising caneffectively eliminate the background noise of the gas liquid two phase flow image,while maintaining the bubble edge features.To meet the demand of gas liquid two phase flow the real-time measurement, theimage connected component labeling algorithms optimized, algorithm of connectedarea marking based on boundary tracings is proposed. The experiment results showthat this algorithm can effectively improve the gas liquid two-phase flowmeasurement speed, and lay a good foundation for the image processing and target detection of gas-liquid two phase flow.In the Visual C++programming environment, with MFC and industrial controlchart ProEssentials, a measurement software is developed for on-line detection andoff-line analysis of gas-liquid two-phase flow parameters. The image processingmodule is designed base on stability and reliability. The target detection module isdesigned base on high-speed and real-time design. According to the principle of visualand GUI,the data display module is designed. The experiment results show that it hasenough function and humanization man-machine interface, and can ensure thehigh-speed gas liquid two phase flow stability measurement.