Research On Thermal Gas Flow Sensor For Mine

Pipeline flow is one of the most important parameters of gas drainage monitored control system.Through continuous monitoring of pipeline flow change in gas extraction system can calculating the efficiency of gas drainage by stages.The gas drainage system can be managed and optimized more effectively and reduce the energy consumption and cost expenditure of coal mine ventilation.By optimizing the gas extraction system,the gas emission during mining can be reduced more effectively and reducing the probability of gas outburst or explosion,realizing Safe Production and Cost Reduction and Efficiency Increase in Coal Mines.The flowmeters widely used in coal industry has obvious defects in measurement range range,pressure loss,application environment,installation and maintenance.The purpose of this project is to design a new type of mine gas flow sensor to overcome and alleviate the above defects.Based on the in-depth study of the current situation and the development trend of flow-meters in domestic and foreign,combined with the actual demand of coal pipeline flow monitoring in China,In this project,a mine thermal gas flow sensor based on heat dissipation effect is designed.In the early stage of the project design,this paper introduces the measurement principle of gas flowmeter in detail,and on this basis,the sensor design scheme based on the heat dissipation constant power method is determined.The hardware of the sensor is based on the LPC1227FBD64 microcontroller of NXP.It adopts modular design scheme and divides the hardware system into power supply module,flow velocity and temperature measurement module,pressure measurement module,MCU module,LCD display module,infrared remote control module,bus communication module and frequency signal output module.The design of the software part includes initialization,remote control settings,velocity and temperature sampling,pressure sampling calculation,flow and temperature calculation,LCD display,frequency output,bus output,etc.It is modularized with the sensor hardware part to facilitate the upgrade and maintenance of the sensor later.At the end of the project,the standard flow generation system is used to calibrate and test the designed sensor.The sensitivity and accuracy of the sensor are verified by analysis of the calibration test data and curve fitting.The experimental results show that the functional indicators of the mine thermal gas flow sensor designed in this paper meet or exceed the requirements of relevant national standards and achieve the expected design goals.