A nonlinear pulse combustor model with an exhaust decoupler and vent pipe was solved using the Poincare-Lindstedt perturbation analysis method. The solutions included expressions for the pressure in the combustion chamber and the exhaust decoupler respectively. Experiments were made to validate the theoretical analysis; results showed that an exhaust decoupler and a vent pipe can affect the frequency of the pulse combustor and the pressure in the exhaust decoupler (both amplitude and phase). There are five main dimensionless parameters: dimensionless exhaust decoupler volume v, dimensionless vent pipe length I, dimensionless vent pipe area s and dimensionless enthalpy h(t0), h(d0). Following the values of these five parameters, the working domain of the pulse combustor was divided into three parts: the inphase zone, critical interval and antiphase zone. In the critical interval domain, the pulse combustor cannot work stable. To make a pulse combustor work at the antiphase zone (recommended in engineering applications), a large exhaust decoupler volume, and fairly long vent pipe with a proper cross-section area are required. (C) 2013 The Combustion Institute. Published by Elsevier Inc. All rights reserved.