Research On The Technology Of Citrus Flesh Splitting Of The Water Jet In Submerged State

Citrus splitting belongs to the labor-intensive links in the process of citrus canning,which completely dependent on labor.But labor costs are huge,and splitting efficiency is low,and the process of food safety and hygiene is difficult to protect,seriously hampered the production efficiency of citrus canned.In this paper,the cavitation effect of submerged jet field is simulated by using citrus flotation technique and CFD numerical analysis method of submerged water jet,and the effects of different nozzle structure and jet parameters on jet performance are simulated.Based on the best matching value,the CFD software and ANSYS Workbench were used to analyze the surface and internal stress distribution of citrus pulp,and the citrus Internal damage mechanism,optimized for jet parameters,Which provides theoretical guidance and technical support for improving the efficiency of citrus flaps.(1)The mechanism of drowned water jet was analyzed,and the citrus material was simplified into plastic material.The shear stress of citrus was the main effect,and the cavitation in the process was not neglected.It is analyzed that the internal flow channel structure and the water jet parameters are important factors influencing the jet flow field performance and the jet striking force.The cavitation effect model is established,and the variation rule of the bubble collapse time under different flow field pressure is simulated.The results show that the higher the flow field pressure,the shorter the bubble collapse,the stronger the erosion and destruction ability.(2)The geometrical model of the flow field inside and outside the nozzle is established and the flow field is analyzed.The effects of different nozzle structure and jet parameters on the flow field performance are discussed.The results show that the core segment of the submerged water jet velocity is shorter than that of the free jet.The effect of the shrinkage angle on the jet velocity in the nozzle is not small,but it has little effect on the velocity of the jet.The smaller the nozzle exit aperture,the jet core speed increases,the jet decay faster,the damage diameter is also gradually reduced.The aspect ratio of the nozzle has a moderate value.(3)The distribution of stress and equivalent stress on citrus surface and internal stress were studied.The results show that when the citrus material is hit by water jet,the center of the contact surface is in the compression state and the compressive stress is the largest.In this process,the maximum shear stress of the citrus material is about 0.5 times the diameter of the nozzle below the center of the impact surface.Further simulation results show that when the spray distance is 50 mm,the stress distribution of citrus material is the best.The simulation results are compared with the experimental data,which verifies the accuracy and rationality of the submerged jet simulation.