Numerical Simulation And Experimental Study Of Temperature Field For Freeze Fabrication Process

Additive manufacturing(AM)is the technology of producing solid parts by gradually accumulating material,which is a kind of "bottom to up" manufacturing method with respect to the traditional material removal and machining technology.In the past years,AM technology has made rapid development.The technology is a new type of manufacturing process without mould and cutting tool,which solves many complex problems that are difficult to be solved in traditional manufacturing process,reducing the working procedure and shortening the manufacturing cycle.Especially for complex parts,its superiority is more prominent.This thesis analyzes the characteristics of additive manufacturing process,and sums up some common principle of additive manufacturing.A brief introduction to the micro droplet jetting molding technology and application in the field is made.The thesis also summarizes the droplet injection molding technology system part.Combining with the development history,also,this thesis summarized the micro droplet jetting forming technology at home and abroad development status.The thesis analyzes the ceramic electric of inverse piezoelectric effect principle,and based on the principle of the piezoelectric ceramic piezoelectric effect,designs the piezoelectric micro droplet nozzle for low temperature deposition forming process.Piezoelectric ceramic has been installed and debugged according to the installation attention to matters and dynamic formula,thus making piezoelectric micro droplet nozzle according to the need of ejecting liquid droplets.According to the first law of thermodynamics,the establishment of energy equation for the temperature field for freeze fabrication process is made.According to the basic theory of thermal transmission,the thesis analyzes the main factors affect the solidification time,and applies of computational fluid dynamics software to make the finite element analysis calculation for freeze fabrication process temperature field model using numerical simulation method.So as to getting the factors that influence on the Freezing time with droplet deposition layer thickness,ambient temperature,initial temperature,this provides the corresponding reference to improve the manufacturing efficiency.The thesis designs corresponding experimental scheme to verify the numerical simulation calculation results.It is proved that the correctness and reliability of the results of finite element analysis.Meanwhile it gets to the deposition of each layer of the short freezing time,which forming to vital role to optimize the deposition forming quality and improve the efficiency of deposition.