An Automatic Online Pressure-type Detection System For Open Channel Flow

As we all know, China is a huge developing country with1.3billion people.Our2.8trillion cubic meters of fresh water resources per person on averagereaches only25%of the world average level. China is one of the countries whichlack of fresh water resources in the world. Environmental pollution andunreasonable usage lead to the waste of water resources. Agriculturalwater accounted for a large proportion of the use of water resources, as theagriculture has always been played a significant role in China; nevertheless, themain reason of agricultural water waste is unreasonable farmland irrigation.Given that open channel flow measurement plays an important role in farmlandirrigation, affecting the water use efficiency and irrigation management directly,it is necessary to explore a new type of open channel flow device and method toensure the reduce the waste of water resources. Meanwhile, almost all existingflow measurement equipment or devices have limitations, for example, highcosts for installation, complicated operation process, higher technicalrequirements for the operators etc. Therefore, after analysing the currentsituation of water resources in China, and referring to a large amount ofliteratures, this paper aims to design an automatic online pressure-type detection system for open channel flow. The velocity measurement of the device is basedon the Bernoulii Equoatin, combining the transmission mechanism of movearound, realizing the measurement from the point to line to surface, and finallyget the flow via the "velocity area method". This device mainly includes5parts:independent developed flow measuring device, mechanical transmission device,MCU, stepper motor, the host computer.This paper describes in detail the design of the automatic onlinepressure-type detection system for open channel flow, the flow measurementdevice, hardware circuit and software design, and also displays the data andanalysis. The paper accomplishes below aspects:1) Given the current status of flow measurement and the limitations ofother devices, it develops a pressure-type flow measurement that can achievereal-time checking and monitoring.2) It designs the mechanical structure of the flow measurement, includingthe outer structure and inner transmission parts.3) It designs the hardware circuit of the flow measurement system:information acquisition module, drive module, power supply module anddisplay module, including component selection, circuit design, PCB circuitboard production.4) It develops the software program for the system, including the lowermachine and the host computer software, and the communications software. 5) The debug for both hardware and software of the system is accomplished.After the debugging, the test and analysis are conducted, demonstrating thefeasibility and accuracy of the system.6) After reviewing the whole the process, it also proposed improvementprogram and expressed the future prospects.The flow measurement system has the advantages of simple operation, smallinterference by external conditions and strong applicability, cost, re-effective,and reducing the waste of manpower. Moreover, it realizes theautomatic measurement of the flow, providing valuable insights and reference forthe automation measurement of open channel flow.