Research On Resistive Grain Moisture Teller Sampling And Optimization Of Structural Parameters

Grain moisture drying is a very important part of the grain production.It’s affect the grain storage,transportation and so on.In order to the implementation of rapidly drying,it need to rely on large drying equipment.But now,the detection and control technology of grain drying in China is still immature.How to detect the grain moisture on-line and how to effectively control the drying equipment become the first problem need to be solved.The moisture teller sampling in this paper is a indispensable part of grain moisture detection system.The stability and effectiveness of sampling determine the accuracy in detection.In the process of grain moisture detecion,based on grain moisture on-line teller which researched by Nanjing Research Institute of Agricultural Mechanization Ministry for Agriculture,making anoptimizationofstructuralparameters,calibrating the sample moisture and making a comparition the difference between detection value and actual value.The main research contents are as follows:(1)Making theoretical analysis and design to the transfer roller and grinding roller.Analyzing the formation of the end curve and deducing the formula of the end curve,building a mathematic model of the main structure in double screw.Making a theoretical analysis of grinding roller dynamic characteristics.In the acceleration area,compression area and rebound area of the transfer roller,made a analysis on pressure distribution.(2)Making simulation on the partical behavior of grain in sampling discrete element.Established three-dimensional model of moisture teller sampling then imported to the discrete element software.The singly transportation impact of pitch and the sufficiency of grinding impact of pattern had been research.It was concluded the line chart between particle number and time in different pitch and also concluded the line chart between pressure and time in different pattern.Then proved the reliability of simulation results through validation test.(3)To determine factor that affect the experimental and determine the primary and secondary relationship among various factors.Building the test bench to do the single factor experimental for every factor and make analyze of test result.Based on single factor experimental,three factors and three levels experimental of response surface optimization test has been carried out,determined the quadratic polynomial mathematical regression model between factors and indexes.Through the fitting function and the analysis of theresponse surface contour,the relationship between factors and response surface,factors and factors has been researched,the best parameter combination of moisture teller sampling has been researched.