The Harmonic Balance Method is one of the most commonly employed Reduced Order Models for turbomachinery calculations, since it leverages signal sparsity in frequency domain to cast transient equations into a coupled set steady-state ones. present work aims at detailing development and validation new framework application open-source software OpenFOAM. paper conceptually divided building blocks...

This paper presents a spectral approach, based on the harmonic-balance technique, for detecting limit-cycle bifurcations in complex nonlinear circuits. The key step of the proposed approach is a method for a simple and effective computation of the Floquet multipliers (FM’s) that yield stability and bifurcation conditions. As a case-study, a quite complex system, Chua’s circuit, is considered. I...

This paper presents an overview of active array antennas, system-level nonlinear effects in such antennas, and their modeling and simulation techniques. Influence of nonlinear distortions and interference in active antennas on the overall system performance is considered. Modeling and simulation techniques, which can be applied to active array antennas, are substantially different from those us...

Superconducting devices are known to produce nonlinear effects. In planar structures, these nonlinearities depend on the current distribution on the strip, which definitely depends on the structure of device. This paper used a numerical method based on 3D-FEM to obtain the current distribution in the open-ends and gaps in the superconducting microstrip structures. This is used to present the no...

In this work we predict the nonlinear behaviour of an eight-pole quasi-elliptic bandpass high temperature superconducting (HTS) filter with an equivalent circuit extracted from intermodulation measurements performed at the centre of the filter passband. We present measurements that show that the equivalent circuit is able to predict the intermodulation products produced by the filter when drive...

Distortion analysis of nonlinear circuits is very important for designing analog integrated circuits and communication systems. In this letter, we propose an efficient frequency-domain approach for calculating frequency response curves, which is based on HB (harmonic balance) method combining with ABMs (Analog Behavior Models) of Spice. Firstly, nonlinear devices such as bipolar transistors and...