Design Of Large Power Discharge Tube Of Fast-axial-flow CO₂ Laser

The working gas of the Fast Axial Flow?FAF? CO₂ laser flows along the discharge tube at a high speed,we use the way of DC or RF excitation to get high beam quality and high laser output power,which is widely used in the area of cutting metal materials and heat treatment.The structure of FAF CO₂ laser affects the output beam quality and power,the optimized FAF CO₂ laser discharge tube can further improve the output efficiency and power.As the traditional discharge tube has the problem of the low output power and efficienc.In this paper we design a new structure of FAF CO₂ laser discharge tube, using the modern computational fluid dynamics method to simulation the discharge tube and verificate the tube experimently,finally we get the optimized discharge tube,which will help to reach much higher laser power. This thesis mainly has the following several aspects:?1? Describes the working principle,system configuration and discharge characteristics of FAF CO₂ laser, analyzes the pros and cons of two common discharge tubes on the aspects of the discharge stability and infuse power limit.?2? Establish a three-dimensional numerical simulation model of the discharge tube,the three-dimensional theoretical model is composed of control equation, momentum equation,mass conservation equation and the equation variables. While the numerical simulation model need to meet several conditions which provides a theoretical basis for high power discharge tube design and simulation.?3? Design the large high-power discharge and simulate it.Theoretically noted that the mass flow rate can be increased to improve the output power of the discharge tube. The processes of using the FLUENT to design the high-power discharge tube have been described including the design of the ring structure, nozzles, straight tube diameter, the size of the entrance and other segments.Finally we design the high-power dischargetube,simulation results proved the high-power discharge tube is superior in the mass flow rate,flow speed, flow field uniformity, temperature distribution,discharge stability of the original CP4000 discharge tube.?4? Verify the newly design discharge tube experimentally.Test the operating voltage and the excitation currents under different output power.The discharge tube can obtain stable glow discharge when the infuse power is between 0W-1656 W.Comparing the high-power discharge tube with the original CP4000 tube, experimental results show that the output power can increase from 333 W to 375 W of single discharge tube.The research results have important significance in capturing the discharge technology and improving the output power and disharge stability.