In this paper, the dynamic simulation for a high pressure regulator is performed to obtain the regulator behavior. To analyze the regulator performance, the equation of motion for inner parts, the continuity equation for diverse chambers and the equation for mass flow rate were derived. Because of nonlinearity and coupling, these equations are solved using numerical methods and the results are ...

we describe a simple model that fits well with iranian economy, and extends a methodology which chary at el. (2007) demonstrated. in addition to four traditional wedges, we introduce additional trade wedge. we then evaluate the contribution of these wedges to the fluctuations in iran during last three years. because of international sanction, trading cost increases, and firms have difficulty to...