Physical Modeling And Experimental Study Of Needle-free Injection For Veterinary Use

Needle-free injection is a new technique that realizes injection by piercing skin with high speed flux.This technique has a wide prospect of application.For vaccination of animal vaccine in large scale breeding,compared to traditional needle injection,needle-free injection of veterinary use has advantages of no cross infection,avoidance of needle break accidents,high efficiency of injection,etc.However,perfect needle-free injection of veterinary use has yet come into domestic market.Therefore,it is necessary to do theoretic and experimental researches on needle-free injection of veterinary use.This paper aims to build a more complete model of needle-free injection of veterinary use,conduct analysis of sealing design,and finally experimentally analyses the impact of systematic parameters of needle-free injection on effect of injection.This will provide references for design of needle-free injection of veterinary use.The content of the paper includes:Building a more complete physical model of needle-free injection by analyzing the process of injection of veterinary use,choosing appropriate systematic parameters to conduct kinematic simulation according to the actual work condition of needle-free injection of veterinary use,and analyzing the impacts of each parameter on flux characters and peak value of the forces acting on the piston;Analyzing the features of sealing structure of needle-free injection of veterinary use and sealing material,introducing the theory of fluid sealing and failure criteria,designing motive sealing and determining the geometry of motive sealing for needle-free injection of veterinary use;Building a simplified model of motive sealing structure on Ansys,conducting simulations of O shape sealing on different compression ratios and fluid stresses,analyzing and comparing of simulation results based on failure criteria,and making relevant conclusions.Inverse solution of elastic fluid dynamics is employed in numerical analysis of film thickness of sealing clearance.The relationships of film thickness generated in process of injection and maximum friction stress with respect to compression ratio and fluid stress,which provides references for design of motive sealing for needle-free injection of veterinary use;Constructing experiment platform for needle-free injection of veterinary use,and by conducting gel injection experiments,obtaining the influences of impact clearance,initial spring compression and spring stiffness on the injection effect.