Simulation And Detection Of Temperature Field In EBW Based On Analysis Of Flow Field

In the numerical simulation of welding process, the accuracy of stress fieldsimulation is based on the accuracy of temperature field simulation, and the key aspectof temperature field simulation is heat source, so it is very important to choosereasonable heat source model. In this article a fitting heat source model to the electronbeam welding was established, and temperature field simulation with experimentalverification was carried out based on the simulation of flow field of weld pool.Based on the characteristics of welding heating, the composite heat source withGauss area heat source and rotary-Gauss body heat source model are used. The physicalmodel of keyhole molten pool of electron beam welding was established by analysis ofthe characteristics of electron beam welding heat process. the simulation of electronbeam deep penetration welding,316L stainless steel EBW molten pool flow numericalcalculation model is used. The results of weld pool fluid field simulation show thatrecoil pressure of metal vapor and surface tension are the main factors affecting fluidflow. In the electron beam welding process, there is a circulation in the surface ofmolten pool under the action of surface tension, the maximum velocity of the fluid was0.389m/s. The liquid metal flowed from the bottom to the top under the action of recoilpressure of metal vapor and surface tension after the keyhole formed, fluid velocitygradually decreased with the increase of penetration in the depth direction. When themolten pool is balanced, weld penetration depth up to the maximum, the weld widthincreases along the width of showing gradual decreasing trend.316L stainless steel of electron beam welding temperature field was simulated byusing ANSYS software. And reasonable experimental verification was designed, theresults of simulation is good agreement with the experiment by analysis of weld profile,the new model is approved to be reasonable for temperature field simulation of EBW.Wireless temperature measuring system in EBW is designed and optimized toverify the rationality of the heat source model, acquisition control software is builtbased on Visual Basic programming language. under the actual electron beam weldingworking condition,50Hz sinusoidal variation of tungsten filament temperature ismeasured, verify the temperature measurement system can realize the welding moltenpool and the surrounding temperature of real-time dynamic measurement, providingexperimental condition for verify the accuracy of the heat source model in simulatetemperature field results.