Development Of Wind Separation Technology And Equipment For Famous And Excellent Green Tea

China is a big tea producer.In 2023,the total area of tea gardens,the output of dried wool tea and the total domestic sales rank the first in the world.However,the raw materials of famous tea are mainly picked manually,and the fresh leaves picked mechanically are generally used to make bulk tea.Tea air conditioning equipment is an important equipment in tea refining,which not only affects the product value,but also affects the efficiency of the next operation.The single equipment function,low precision of air selection,high error rate of Chinese tea wind selection leads to the low efficiency of tea wind selection.Based on this,this paper designs a famous green tea air separation equipment,explores the working principle of the air separation equipment,designs the air separation chamber,control system and material transfer system,optimizes the internal structural parameters,adopts the method of combining fluid mechanics and discrete element simulation to conduct numerical simulation of the air separation process,and through prototype trial production and performance test,The rationality of the design parameters of the air separation equipment and the stability and reliability of the equipment are verified.The main research contents are as follows:（1）The physical and aerodynamic characteristics of tea were analyzed.According to the difference of bulk density and porosity of tea,the tea was screened by air separation to remove impurities and achieve tea classification.The tea trajectory equation and the aerodynamic flow field equation were established,and the relationship between single particle and particle group was analyzed.The advantages and disadvantages of different turbulence models were analyzed,and the standard k-εmodel was used to simulate the Fluent software,which provided theoretical support for the design of tea air separation equipment.（2）Design the famous green tea wind selection equipment.This paper analyzes the problems existing in the current tea air separation equipment,designs the famous green tea air separation equipment according to the working principle of the air separation equipment,expounds the basic structure and working principle of the air separation equipment,and determines the relevant design parameters of the air separation room,fan,transmission device and material transfer device.（3）The feasibility simulation analysis and key parameters determination of the wind separation equipment for famous and excellent green tea were carried out.The flow line,velocity and pressure of the flow field in the air separation room were studied based on the fluid dynamics simulation method.The air separation status of tea particles at different moments was simulated based on the discrete element simulation method.The influence of different wind speed on the effect of tea separation was explored.（4）Carried out the prototype test of famous and excellent green tea wind separation equipment.After the prototype was completed,the performance test and the effect test of the air separation equipment were carried out,and the influence of different running frequency on the effect of air separation and different air separation sequence on the quality of the finished tea was explored.The test results show that the performance test indicators meet the requirements of national regulations;The fresh tea leaves and green killing leaves were improved from grade B to grade A-and A,the stripe rate of two green leaves and three green leaves was higher than 90%,and the check rate of tea was higher than 90%.When the fan operating frequency is 35Hz,the air separation effect is the best.The quality of tea was the best when the wind selection order was Erqing classification,and the sensory evaluation score of O₂main tea outlet tea was the highest.