Integrated Platform Design Of Flow Parameters Measurement For Gas-solid Two-phase Flow

For the characteristics of spatial distribution,heterogeneity of flowing process,the measurement of gas-solid two phase parameters was an urgent technology challenge in industry application.Various detection method based on different principles was created to solve these problems.While different method owned different advantages and weakness,it was difficult to realize the best optimal combination of various detection methods for the unique application scope.Therefore,it was necessary to design an integrated platform of flow parameters measurement for gas-solid two-phase flow,which can complete the function of comprehensive measurement of different detection principles.In this thesis,a new capacitance measuring method of Direct Sensor-to-Microcontroller Interfaces(DSTMI)was researched,which was based on the analysis of average solid phase concentration,distributed solid phase concentration,average solid phase velocity,and distributed solid phase concentration.According to the requirements of above various detection methods,the hardware and software for measurement platform of flow parameters were designed from the perspectives of instrument functions and method extension,which realized the accurate measurement of flow parameters.The main work of this thesis was as follows:(1)Analyze the mechanism of different detection methods of solid phase parameters,such as DC charge and discharge measurement and AC excitation measurement.Put forward the DSTMI,which owned the advantages of simple circuit,clear operation process,and unlimited theoretical measurement range.Based on the research of the coupling path of stray capacitance,which had an effect on the capacitance measurement,an enhance Direct Sensor-to-Microcontroller Interfaces(EDSTMI)was created to improve the measurement result;(2)Design the measurement platform of three cores structure based on the LPC4337 and ATmega2560.The microcontroller ATmega2560 was used to realize the instrument control function,and the microprocessor was used to complete data acquisition,digital signal process,high speed communication,and SRAM data story.The efficient signaling interaction mechanism between the two CPUs also was designed;(3)Fulfill the system hardware design,which included the power supply system based on Mornsun wide input voltage power supply model WRA24XX,instrument control system of ATmega2560,temperature measuring circuit of three-wire principle for PT100,virtual key of resistive touch screen,communication circuit of electromagnetic isolated RS 485,communication circuit of standard 4-to-20mA signal,Bus control interface for different measurement boards,analog to digital conversion circuit based on the CORTEX-MO core of LPC4337,RS-232communication interface,USB interface,SPI interface,and extended 16bits SRAM based on the CORTEX-M4 core of LPC4337;(4)Fulfill the system software design,which included the control task scheduling system of ATmega2560,task menu program of signal acquisition selection of LPC4337,interactive command menu program,curve display and virtual key press code,communication driver program,FIR filter program,extreme value and three times variance filter program,cross-correlation velocity calculation program,the interactive program between the ATmega2560 and LPC4337,and the interactive program between the dual cores in LPC4337;(5)Fulfill the design of standard interface for different detection measurement.Complete the measurement board design of the standard interface based on different principles,which were used to detect the average concentration,distributed concentration,average velocity.The measurement platform was provided to be able to work normally in the laboratory environment.And large number of experiments for various parameters based on different was conducted to achieve high accurate measurement result.The integrated platform was able to provide resourceful interfaces for other new detection methods of different principles.