Explicit asymptotic modelling of transient Love waves propagated along a thin coating

The official published version can be obtained from the link below.An explicit asymptotic model for transient Love waves is derived from the exact equations of anti-plane elasticity. The perturbation procedure relies upon the slow decay of low-frequency Love waves to approximate the displacement field in the substrate by a power series in the depth coordinate. When appropriate decay conditions are imposed on the series, one obtains a model equation governing the displacement at the interface between the coating and the substrate. Unusually, the model equation contains a term with a pseudo-differential operator. This result is confirmed and interpreted by analysing the exact solution obtained by integral transforms. The performance of the derived model is illustrated by numerical examples.This work is sponsored by the grant from Higher Education of Pakistan and by the Brunel University’s “BRIEF” research award

Usporedba zrcalnog modela i modela prijenosnih linija u analizi horizontalne žičane strukture iznad dvoslojnog tla

The paper presents comparison between two approximate models of energized horizontal thin-wire conductors above two-layer soil. The formulation is posed in frequency domain by using two approaches. The first one is based on quasi-static image theory within Mixed Potential Integral Equation. The second one is based on transmission line theory with approximation of per unit length parameters. The authors compare currents computed by the both approximate models of a center fed wire to establish the computation errors over a wide frequency range. The main objective is to validate the proposed image and transmission line models for various lengths of wire conductors, and various cases of low and high conductivities of two-layer soil. The verification of the results is done by comparison with exact model based on full-wave theory. Detailed parametric analysis clearly illustrate validity domain and problems when using both approximate models with respect to their use in practical EMC studies.U radu je prikazana usporedba dviju približnih modela analize pobuđenog horizontalnog tankog žičanog vodiča iznad dvoslojnog tla. Formulacija problema je izvedena u frekvencijskoj domeni pomoću dva pristupa. Prvi pristup se temelji na kvazi-statičkom zrcalnom modelu unutar integralne jednadžbe s mješovitim potencijalima. Drugi se temelji na teoriji prijenosnih linija s aproksimacijom jediničnih parametara. Autori su usporedili distribucije struje izračunate s pomoću obje približne metode kako bi odredili pogrešku metoda u širokom rasponu frekvencija. Glavni cilj bio je potvrditi predloženi zrcalni i linijski model za različite duljine žičanog vodiča i razne slučajeve niske i visoke vodljivosti slojeva tla. Provjera rezultata obavljena je usporedbom s modelom bez aproksimacija temeljenog na punovalnoj teoriji. Detaljna parametarska analiza jasno pokazuju valjanosti domene i vrste problema uz korištenje obje približne metode s obzirom na njihovu primjenu u praktičnim EMC razmatranjima