Efficient computation of electrical Laslett coefficients for rounded-rectangular pipes


We present an effective numerical technique for computing the electrical image coefficients for rounded rectangular pipes with perfectly conducting walls. The method of moments is used to solve the involved boundary-value problem in integral form, by means of(a rapidly converging representation of) the rectangular-domain Green’s function, together with a set of piecewise parabolic subdomain basis functions, yielding high speed and accuracy, with minimum storage budget (no prior meshing required). As a distinctive feature of the proposed method no numerical differentiation is required, resulting into far better accuracy as compared, e.g., to finite-element and finite-difference methods. Application to some simplified cross section geometries relevant to LHC (square with rounded corners, stadium and cut-circle)are presented. As a check of accuracy of the proposed approach, a comparison with available exact (analytical) results for the circular pipe (hardest possible benchmark), shows an excellent agreement.

Particle Accelerators 63, 37