Computer simulation.

Abstract

Available techniques for computer simulation are described (computer languages, software modules) and the particular requirements for fluid power system modelling are considered. A description of a block diagram analysis method is given. Hydraulic components are classified into energy-storing, energy modulating, and energy coverting components, and energy sources and sinks. Numerical methods for solving such computer models are listed: method of characteristics, impedence methods, various numerical integration techniques etc. Problems of validating models are considered. The problem of mathematical rigidity of the system model is outlined and related to fluid compressibility. As an example of modelling, the hydraulic system of a Royal Navy frigate helicopter deck is considered; the helicopter manoeuvering system operates three winches to enable machines to be positioned anywhere on the deck. Basic features of the simulation model are described, and experimental results are compared with model predictions. Some general conlusions are drawn on computer modelling of fluid power system using separate component models. Note: the references referred to in the text have been omitted. (C.C.B.)