(96g) Measurement of Solid Mass Flow Rate Under Different Flow Regimes in Pneumatic Conveying By Non-Intrusive Acoustic Emission Detection

As energy consumption is the most important in pneumatic conveying process, it is always recommended to be operated at the boundary between the dilute phase and the dense phase conveying. However, the flow regime in this operating zone is variable, which makes the real-time monitoring of the process very difficult, especially for measurement of solid mass flow rate. At present, most of the solid mass flow rate prediction models are only applicable to a specific flow regime, and when the flow regime changes, the prediction effect is poor. Therefore, we want to develop a solid mass flow rate prediction method that can be used under different flow regimes with good extrapolation by using non-intrusive acoustic emission detection. The implementation methods include the following two ways: (a) The feature quantities (including flow characterization parameters) obtained by analysis of acoustic signal are directly substituted into the prediction model for measurement of the solid mass flow rate. (b) The flow characterization parameters is used for flow regime identification, and then predict the sloid mass flow rate for each flow regime separately. The calculation results show that the accuracy of the prediction model is strongly dependent on the flow regime. For different prediction ways, the addition of flow characterization parameters can improve the prediction accuracy of the model. For prediction method (a), the predicted average relative error is 7.5%. For prediction method (b), the predicted average relative error is about 22.0%. The predicted average relative error of both methods are lower than the method which cannot be extrapolated (28.0%).

Keywords: pneumatic conveying, mass flow rate, acoustic emission detection, extrapolation