Characteristics And Infrared Spectroscopy Analysis Of Chinese Medicinal Materials Drying By High Voltage Electric Field

Traditional Chinese medicine is an important cultural treasure of our country.Among them,Chinese medicinal materials are important materials related to the curative effect of Chinese medicine,and drying is an important part of the post-processing of Chinese medicinal materials.This paper uses high-voltage electric field drying.The article first uses the theory of electrodynamics to analyze the electric field characteristics of the tip discharge and ANSYS MAXWELL analyzes the tip electric field distribution and energy distribution under the high-voltage electric field.Through the simulation of the high-voltage electric field,the voltage magnitude,voltage polarity,and needle are obtained.The characteristics of spacing,needle-plate spacing,electrode material,electric field intensity distribution and energy distribution.Select the best parameters,and use the high-voltage electric field drying method to dry the Chinese medicinal materials,and compare them with the traditional drying methods to analyze the characteristics of the infrared spectrum.Provide research results and sufficient theoretical analysis for the drying technology of the Chinese herbal medicine industry in our country.The main theoretical analysis and research results of this paper are as follows:(1)This article uses the knowledge of electrodynamics,Maxwell’s equations,and the Laplace equation in the spherical coordinate system to carry out theoretical analysis of the tip discharge.Theoretical analysis results show that: in calculating the electric field characteristics of the tip discharge,the tip can be equivalent to an inverted conical cavity,and the expression of the electric field strength can be obtained.For the actual calculation in the future.(2)The high-voltage electric field drying adopts the needle-plate/net electrode drying system,and uses ANSYS MAXWELL to simulate the influence of different voltages,voltage polarity,needle spacing,and electrode materials on the electric field characteristics of the needle-plate high-voltage electric field.The simulation results show that the electric field intensity and energy of the needle-plate/mesh electrode drying system increase with the increase of the voltage of the high-voltage electric field,but in the actual test,the excessive voltage will cause the breakdown of the air medium,which affects the test.Under the same parameters,the electric field strength and energy of the needle-plate/mesh electrode drying system under the negative polarity voltage are greater than those under the positive polarity voltage.It is obtained by comparing the electric field strength of the needle-plate/mesh electrode drying system with different needle spacings.When the needle spacing is 20 mm,in the control group,the electric field intensity and energy are both the maximum.By simulating the electric field characteristics of Ag electrode,Cu electrode,and Fe electrode under high-voltage electric field,the order of electric field intensity and energy under high-voltage electric field is that Ag electrode is greater than Cu electrode and Fe electrode.(3)The simulation results are verified by the high-voltage electric field drying of Gastrodia,yam,and Houttuynia cordata.The test results show that in the high-voltage electric field drying,the moisture content of the Chinese medicinal materials under the negative voltage is higher than the positive voltage in the same drying time.To be lower,the drying rate is faster than the positive polarity voltage.Due to the high cost of Ag electrode,in order to reduce the cost,a comparative test between Cu electrode and Fe electrode was used in the experiment.The results showed that in the high-voltage electric field drying,the moisture content of the Chinese medicinal materials under the Cu electrode was higher than that of the Fe electrode during the same drying time.The moisture content is lower and the drying rate is faster than that of Fe electrodes.(4)Through infrared spectroscopy experiments of gastrodia elata,yam,and Houttuynia cordata under high-voltage electric field and hot-air drying,it is found that the quality of Chinese medicinal materials under high-voltage electric field drying is better than that under hot air drying,and it is better than hot air in maintaining nutrition and medicinal ingredients.The drying is maintained well,and the content of each component is obviously higher than that of the hot air drying.