Abstract
A new simulation technique called the “system modal approximation” method for fluid transients in compound fl uid-line systems composed of many line elements is developed and presented. This new method is based on numerical modal approximation of the frequency transfer function itself of the output to the input, considering the total system dynamics. This simulation technique also has the feature that the line elements with any kinds of the dynamic characteristics can be applicable because only the numerical data of the frequency response of transfer matrix parameters of individual line element is needed, and that the computation time is very short because the output in time domain can be calculated by the simple algebraic expression in the form of a recurrence formula. Simulation results of this method for the pressure transients in typical three kinds of compound fluid-line are compared with both the solutions from the method of characteristics and experimental results, and the superiority of this technique in easy applicability, flexibility, accuracy, computation time, etc. are demonstrated.
