Design of experimental test rig for bulk vertical grain elevation by entrainment type
[Objective]This study aims to explore the relationship between the efficiency of a sandwich belt high angle conveyor for bulk grain and its structural and operating parameters.The goal is to identify the feeding and conveying parameters that yield the highest efficiency.To achieve this,it is necessary to build an experimental platform in a university laboratory setting.This platform should facilitate the efficiency and performance testing of the bulk grain sandwich belt high angle conveyor,allowing for experimental investigations into the correlation between various parameters and elevator performance.These parameters include the pressure supply of the conveying structure,position of the bed idlers,linear speed of the belts,feed rollers of the feeding device,geometric positional relationship between the axis of the feeding device,line of the bed idlers,and performance.The results of these experiments will serve as a valuable reference for optimizing the operation of the vertical elevator of the entrainer and enhancing the educational experience in grain machinery for undergraduate and graduate students.[Methods]We developed an sandwich belt experimental platform to test the efficiency and performance of high angle conveying.This platform includes a feeding structure,sandwich belt high angle conveying structure,and control structure.The experimental platform can adjust the distance between the feeding device and the high angle conveying section to accommodate different materials and adjust the clamping force of the belt on the material by modifying the input airflow parameters.Additionally,a belt scale in the horizontal transportation section enables real-time monitoring of the material volume lift efficiency.A vibration acquisition system is also integrated to detect the vibration characteristics of specific points on the high angle conveying section under different input conditions during the transportation process.Through the analysis of the vibration signals,we can determine how the clamping force and feeding parameters affect the transportation quality.This insight is invaluable for promoting the structural improvement of high angle conveyor systems.[Results]The vibration signal analysis of the belt revealed a transverse vibration displacement-time curve at the middle position of the high angle conveyor system and helped identify the common vibration frequency between the belt and material according to the time function.By determining the natural frequency of the composite structure with different materials and filling levels,we pinpointed the frequency ranges to avoid during operation to enhance the conveyance stability and quality.[Conclusions]The experimental platform demonstrates how the regulation parameters influence conveying quality through vibration signals.By applying statistical methods and data analysis,we confirmed that the vibration signal analysis during high angle conveying aligns well with the actual conditions.This provides theoretical support for the real-time condition monitoring of sandwich belt conveyors as they evolve toward unmanned and intelligent operations.The platform's various experiments will assist the teaching of specialized courses,support the development of disciplines,bridge the gap between engineering practice and theoretical teaching,and support the cultivation of innovative talent.