Study On The Extraction Force Of Carrot Based On EDEM

Carrot is the main vegetable species in China,but at the present stage,the harvest level of carrot modernization in our country is relatively low.In order to analyze the mechanism of interaction between carrot and soil during mechanical extraction,support was provided for the development of carrot extraction combined harvesting machinery.This article uses a selfdeveloped numerically-controlled vegetable extraction force measurement test stand,carrots were extracted from the typical varieties of carrots during harvest.Based on the discrete element simulation software,the soil-carrot model of carrot extraction process was established,and the regression analysis was performed using the statistical analysis data of professional function mapping software Origin Pro 2015 to study and predict the carrot geometric characteristics(carrot surface area,volume);the carrot extraction method(pulling speed,picking force inclination angle);soil physical properties parameters(soil moisture content,hardness and bulk density)in the process of extraction and carrot extraction force and the dynamic process of the relationship between the extraction.Analyze the disturbance of carrots on the soil during the extraction process,and discuss the influence of the main working parameters on the mechanical extraction force of carrots during mechanical extraction.The final result shows:1)The greater the surface area and volume of the carrot,the greater the extraction force.The greater the picking speed and extraction force angle when pulling out the carrot,the greater the pulling force.When the pulling force was along the growth direction of the carrot,the pulling force was the smallest,and when the pulling force was more than 6°,the pulling force rose rapidly with the increase of the tilt angle.2)When the soil moisture content is between 20% and 30%,with the increase of soil moisture content,the decrease of soil hardness and the decrease of soil bulk density,the mechanical extraction force value of carrots will be reduced,but the time taken to remove carrots from soil will be prolonged.3)The maximum value of mechanical extraction force of carrot appeared in the early stage of extraction process.The disturbance area of carrot soil by mechanical extraction of carrot showed a inverted cone shape.The larger the disturbance area,the greater the extraction force.In this study,the extraction mechanical properties of harvested carrots were studied,and the results of field experiments were simulated using the discrete element simulation software EDEM,which provided theoretical support for the structure and working parameters of the extracted carrot harvester.