Dynamic Analysis of a Complex Pneumatic Valve Using Pseudobond Graph Modeling Technique

Abstract

In this work, the dynamic behaviors of a complex pneumatic reducer valve have been studied through the pseudobond graph modeling technique. This modeling approach graphically describes the energy and mass flows among pneumatic valve components during real operational conditions. State equations have been derived from the pseudobond graph model and have been numerically solved by matlab-Simulink. To validate the accuracy of the model, simulation results are compared with the real data of an experimental setup and good agreements between them are reported. The main advantage of the proposed model over other conventional approaches such as fluid dynamics theories is that it provides a physical model which accurately predicts the system's dynamic responses without any need to run huge computer programs or establish expensive experimental setups.

Energy-based viscoelastic model: a physical approach for material an elastic behavior by the bond graph approach

“…The difference between the orders of R m and R e can explain this claim. By implementing Equations (17) and (13) in Equations (24) and (26), for a uniformly discretized homogeneous material, one can present the flowing relaxation time for both the kinetic and potential subdomains:…”

“…To generate such a physical viscoelastic model suitable for multi-physical system dynamic investigations, the bond graph (BG) modeling technique [13][14][15][16][17][18][19] is suggested in this paper. Working on the basis of physical system theory, the BG technique provides a continuous power exchange frame between the existing physical subdomains of a multiphysical system, and produces the behavior of the system on the basis of power conservative interactions between the existing energetic components of the system.…”

Non-linear analysis of hydro-mechanical interactions in control devices during transient period: Bond graph approach

“…The pressure regulator shown in Figures 1 and 2 was chosen for start period modeling. The control valve is composed of four major parts: (a) Control Part -including inlet (1), outlet (2), and control orifice (5), the size of which is changed by movement of the control spool (3); (b) Amplifying Part (where the pilot signal is regulated and amplified) -including control piston (4) and the damping orifice that connects the piston front zone (ppf) (17) and piston back zone (ppb) (18); (c) Adjusting Part (which regulates and sends the hydro-control signal to (a)) -including adjusting spool (9), flexible elements (16), feedback pipe (7), and adjusting orifice (15); (d) Preadjusting Part (where initial adjustment of the valve is imposed) -including adjusting screw (13), noise canceler (11), and adjusting spring (12).…”

“…7 Dasgupta and Watton studied the performance of a multiple-input multiple-output pilot relief valve with parameter variations 8 ; the system was then modeled using measured parameters and analyzed in the transient and steady state. 9,10 Zanj et al developed nonlinear BG models of direct and indirect pressure control valves, 11,12 and investigated a range of dynamic behaviors of an indirect valve including nonlinear effects of flow forces, Coulomb friction, hydraulic resistances, and fluid chamber compressibility 13 ; the model was validated by experiment. None of these studies attempted to model the start period, as the traditional single-model BG approach used can only describe fixed degree-of-freedom (DoF) dynamics, whereas the dynamics of the start period are varying DoF in nature.…”

Dynamic modeling and simulation of an integral bipropellant propulsion double-valve combined test system

“…As a component for reducing and stabilizing pressure in the fluid pipeline system, the PRR is widely researched [11][12][13][14][15][16][17][18][19][20][21][22][23] for its dynamic characteristics. However, many models for gas PRR adopt some assumptions such as isothermic [12,13], isentropic [14][15][16] and linearization [15] which do not strictly agree with reality. Their pressure differential equations are usually obtained by taking the derivative of ideal gas state equation or isentropic equation and employing isothermal process assumption [12] or isentropic process assumption [15,16] rather than by deduction from the energy equation of compressible transient flow in one-dimensional (1D) conservative form.…”