To study system-generated electromagnetic pulse(SGEMP) produced by complex model, a 3D particle in cell (PIC) code is exploited. A function module is appended to characterize cosine angular distribution and exponential energy spectra of photoelectron. For validation, external SGEMP effects induced by photoelectrons emitted from cylinder top surface is simulated and are compared with those by 2D code from literature. Subsequently, external SGEMP effects induced by photoelectrons emitted from half-side surface of a cylinder are studied. It shows that intense of electric field could get 56 kV·m^-1 and magnetic field is 3.0×10^-6T as emitting current is 3.3 A.

A brief introduction to development history of computational electromagnetics(CEM) and numerical methods in CEM is provided. In addition, we discuss up-to-date progress of CEM in scientific researches, commercial softwares and proprietary softwares. Considering applications of electromagnetics environmental effects (E3), we present development of our numerical simulation platform of E3. Finally, future trends of development in E3 are shown.

Nine.point scheme for diffusion equation on distorted quadrilateral is discussed.Based on a classical nine。point scheme, and with continuity of diffusion flux, a formula for designed for computing Vertex unknowns. Numerical experiments show that the scheme is robust,and the accuracy is higher than that of other weighted methods for diffusion problem with continuous or discontinuous coefficient on distorted meshes.

A method that decreases useless magnetism pressure to amplify the power of MFCG(magnetic flux compression generator) is proposed, in which the charging loop is cut off after initial current is provided.By code MFCG(V),the simulation demonstrates effectiveness of the method.

In this paper, the equations of FEL amplifier with aplanar wiggler are derived. FBC code based on equations is designed by H.P.Freund. WAGFEL code based on KMR theory are designed by us. Although there are obvious differences between WAGFEL and FBC code, in dealing with practical problems such as magnetic field and length of the entry wiggler, initial distribution of electron beam, fashon of the downstream tapered wiggler etc, a set of c-oupled nonlinear differential equations used in two codes is based on single-particle theory. Meanwhile, under the certain conditions, the computational results of both WAGFEL and FBC code coincide with those of the experiment well. Then the computional results used by WAGFEL and FBC code are compared.The results of TE₀₁ mode calculated with WAGFEL and FBC code are compared and analyzed under the condition of the constant and varyable amplitude of wiggler magnetic field B_w, respectively. The analyzed results show that regard the conditions and results of experiment as criterion, WAGFEL code is more useful in comparing similation results with experiment than FBC code. As a result, not only data of 4MeV amplifier which are computed by WAGFEL code are valuable, but WAGFEL code is feasible to design amplifier and study problems of FEL.

In this paper, the analytical solutions of equations of electron betatron motion are derived by W·K·B method for parameters of varyable B_wand γ. with the formula, the reasons that electrons run out of the waveguide are analyzed. Meanwhile, we have compared the analytical results with those which are simulated by WAGFEL code Under certain conditions, analytical results coincide with simulation results well.