Research On Calibration Technique In Concentration Measurement Of Multiphase Flow Particle

By studying the influence to the transmission characteristic of particles to the laser in a multiphase flow system, this paper selects a gelatin as a laser transmission medium and uses the optical transmission method of laser transmission to establish the correspondence relationship between the optical transmittance and the particle concentration of standard sample block. The feasibility of the research methods is also verified in this paper.Multiphase flow system is featured by complex, changeable, and difficult to establish the model. Most research is focused on simplifying the multiphase into bi-phase flow system based on model establishment. Laser is a crucial means in the measurement of the multiphase flow system. By measuring the laser, the particle concentration can be accurately calibrated. The main laser measurement methods are optical transmission method and the optical scattering method,Considering the special advantages of laser on monochromeeaticity,coherence, and directivity, this paper selects the optical transmission method to conduct the experiment. Among the two commonly used media, gelatin and gel, the gelatin is selected due to its stable chemical properties, good transparency, and easy to implement. The optical signal is converted to an electric signal during the experiment for recording and observing.This paper shows the pertinent data of the detected voltage changing alongside the optical path and the detected voltage changing alongside the concentration. This paper also studies the variation of the particle concentrations under different circumstances and the error analysis. Finally, this paper carries out the curve fitting between the data of the single-point concentration measurement and the data of the multi-point concentration measurement, based on the Matlab curve algorithm with a focus on the method of the least square. The correlation between the particle concentration and the detected signal can be accurately described and the particle concentration in the multiphase flow system can be calibrated.In the experiments, the error of the particle mass concentration curve is analyzed through calibration and data processing. Nevertheless, this experiment is of practical value in that it realizes the calibration of the particle concentration.