The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,t...The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,three calculation methods for the temperature field are given.First,the finite element model of the temperature field before forging rail flash welding is established by using the transient heat module of Ansys software and verified by infrared temperature measurement.Second,the temperature distribution of different parts of the rail before flash welding is obtained by using infrared thermal imaging equipment.Third,Matlab software is used to calculate the temperature of the non-measured part.Finally,the temperature distribution function along the rail axis is fitted through the temperature measurement data.The temperature distribution before the top forging of the rail flash welding can be used to analyze the joint and heat-affected zone organization and properties effectively and to guide the parameter setting and industrial production.展开更多
With the development of gravity gradient full tensor measurement technique,three-dimensional( 3D) inversion based on gravity gradient tensor can provide more accurate information. But the forward calculation of 3D ful...With the development of gravity gradient full tensor measurement technique,three-dimensional( 3D) inversion based on gravity gradient tensor can provide more accurate information. But the forward calculation of 3D full tensor sensitivity matrix is very time-consuming,which restricts its development and application.According to the symmetry of the kernel function,the authors reconstruct the underground source of geological body to avoid repeat computation of the same value,and work out the corresponding relationship between the response of geological body to the observation point and the response of reconstructed geological body to the observation point. According to the relationship,rapid calculation of full tensor gravity sensitivity matrix can be achieved. The model calculation shows that this method can increase the speed of 30-45 times compared with the traditional calculation method. The sensitivity matrix is applied to the multi-component inversion of gravity gradient. The application of this method on the measured data provides the basis for the promotion of the method.展开更多
基金supported by the China National Railway Group Corporation Science and Technology Research and Development Program(J2022G009)Dr.Jingjing Li received no grant support.
文摘The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,three calculation methods for the temperature field are given.First,the finite element model of the temperature field before forging rail flash welding is established by using the transient heat module of Ansys software and verified by infrared temperature measurement.Second,the temperature distribution of different parts of the rail before flash welding is obtained by using infrared thermal imaging equipment.Third,Matlab software is used to calculate the temperature of the non-measured part.Finally,the temperature distribution function along the rail axis is fitted through the temperature measurement data.The temperature distribution before the top forging of the rail flash welding can be used to analyze the joint and heat-affected zone organization and properties effectively and to guide the parameter setting and industrial production.
基金Support by Project of Geophysical Comprehensive Survey and Information Extraction of Deep Mineral Resources(2016YFC0600505)
文摘With the development of gravity gradient full tensor measurement technique,three-dimensional( 3D) inversion based on gravity gradient tensor can provide more accurate information. But the forward calculation of 3D full tensor sensitivity matrix is very time-consuming,which restricts its development and application.According to the symmetry of the kernel function,the authors reconstruct the underground source of geological body to avoid repeat computation of the same value,and work out the corresponding relationship between the response of geological body to the observation point and the response of reconstructed geological body to the observation point. According to the relationship,rapid calculation of full tensor gravity sensitivity matrix can be achieved. The model calculation shows that this method can increase the speed of 30-45 times compared with the traditional calculation method. The sensitivity matrix is applied to the multi-component inversion of gravity gradient. The application of this method on the measured data provides the basis for the promotion of the method.
