| The velocity area method is used to measure the water flow in open channel,the sludge precipitation where in open channel can impact water cross section area,and make water cross section area can’t measured accurately,resulting in the water flow can’t measured accurately.In order to measure the accurate water flow rate in channel,a measuring method and apparatus is needed,which can measure the thickness of the mud and the level of water at the same time.According to the nature of different medium has different conductivity to distinguish the all of mud,water and air,after analyzing common measurements,determine to use the resistance method of partial pressure to measure the both of water and mud,after analyzing lots of experiment data,design a suitable algorithm,and determine the electrode layout form and acquisition method,then develop a hardware and software system of measuring device for water mud levels.The hardware of system uses IAP15W4K61S4 type SCM as micro-controller,gets the voltage value of electrodes by acquisition circuit,uses 24LC1025 chip to store data,in order to satisfy the requirement of explosion protection standard,design a power supply which has two-stage protection circuit on system,takes RS485 to transmit the data.Write a matched system software program which can realize many functions,such as data collection,AD conversion,data processing and storage,communication between the device with upper machine,system initialization,etc.By writing the code generate PC display,which can set up parameters and get lots of data,such as water value,mud value,AD voltage acquisition value and parameters.Run and test the device,and analyze the error on measuring data,draw a conclusion what the error within ± 5mm,and the device can measure results timely and rapidly,these are in line with the requirements of the original.This device can be used in the coal mine open channel where the sludge pollution is serious,can collect data in real-time automatically,it not plays a very important role for the prevention of mine water inflow,but can monitor the flow of water reservoirs,rivers,water conservancy project,urban water supply,sewage treatment,irrigation,water policy and resource,etc. |
