Mathematical model construction and verification of soil and Panax Notoginseng root adhesion

Abstract: The roots of Panax Notoginseng are intertwined with cohesive soil to form a solid root-soil complex, so the harvesting process of Panax Notoginseng is easy to cause incomplete root and soil separation and serious root damage, resulting in low efficiency of Panax Notoginseng harvesting and serious economic losses. Because there is an interface adhesion form between soil and Panax Notoginseng root system, from the micro level Panax Notoginseng and the adhesion properties of soil, calculate the adhesion force between soil and Panax Notoginseng, is to explore the theoretical basis for efficient root soil separation methods, to improve the efficiency of Panax Notoginseng root soil complex separation and separation quality, to quantify Panax Notoginseng roots and soil adhesion force value. The average particle size of Panax Notoginseng soil is 0.058 mm and the average moisture content is 20.95%. Based on the theory of soil adhesion water film, “high energy layer” theory, and capillary theory, the influence of soil properties, water content, porosity, the contact area between soil and root of Panax Notoginseng and surface roughness of rhizome of Panax Notoginseng on the adhesion of Panax Notoginseng soil complex was analyzed, and the mathematical model of adhesion of Panax Notoginseng soil complex was derived. Using environmental scanning electron microscopy (SEM) analysis of soil porosity distribution and the relationship between soil moisture content, fitting the mathematical relationship of soil porosity and moisture content results show that the experiment samples and the soil porosity are positively correlated with moisture content and moisture content of soil porosity by linear representation, Panax Notoginseng planting soil and smooth solid adhesion between strive to take formula. The adhesion force formula was further refined, and the surface morphology and roughness of Panax Notoginseng were characterized by environmental scanning electron microscopy and an optical profilometer. The results showed that the surface roughness of Panax Notoginseng is significant at the nanometer scale, the surface roughness of Panax notoginseng is 4.14. Therefore, the effect of surface roughness on the adhesion force of Panax Notoginseng could not be ignored. The intuitive surface area and roughness factor of Panax Notoginseng in different shooting areas were calculated, and the relationship among surface roughness factor, intuitive surface area, and actual surface area of Panax Notoginseng was analyzed. By fitting, the actual surface area of Panax Notoginseng was expressed as a binary quadric form by the roughness and intuitive surface area. According to mentioned above experiments, the mathematical model of soil-solid adhesion of Panax Notoginseng was established by introducing the soil parameters and the actual surface area function of Panax Notoginseng. In conclusion, according to the adhesion force calculation formula derived in this study, the average intuitive surface area of Panax Notoginseng root in the harvest area could be measured by sampling, and the actual surface area of Panax Notoginseng root could be calculated, which solves the difficult problem of actual surface area measurement of Panax Notoginseng root, and then the average adhesion force of Panax Notoginseng soil complex in the harvest area could be calculated. The adhesion test of Panax Notoginseng root soil was carried out to verify the feasibility of the mathematical model. The results showed that the relative error between the adhesion value obtained by the proposed mathematical model and the test adhesion value was 5.65%, indicating that the model was accurate and reliable. It provides a scientific theoretical basis for designing and optimizing operation parameters of the root soil separation unit of Panax Notoginseng harvester. At the same time, the quantitative study of adhesion between soil and Panax Notoginseng was made up.