The increase of system dynamic within the area of pneumatics requires sophisticated numerical methods to determine the systems’ performance. Cycle durations in the range of just a few milliseconds and below violate the assumption of a stationary process. State of the art pneumatic calculations are built upon this assumption and, therefore, gas dynamic solvers have to be used to predict the systems’ behavior accurately.
In general it is possible to calculate several flow parameters for transient gaseous flows using computational fluid dynamics (CFD) software, but despite increasing processing power of modern computers, solving particular problems is yet time-consuming. A simulation of a few milliseconds results in a computational time of several hours which makes the design of a highly dynamic pneumatic system lengthy.
This paper presents a one dimensional transient numerical model which is capable of computing a transient pneumatic system’s performance time-efficiently yet retaining the accuracy of a CFD simulation. It allows to determine flow parameters, e.g., density, pressure and velocity, within transient gaseous flows including discontinuities.
In particular the proposed model depicts an approach to calculate transient flows with discontinuous flow curvature. Such jumps naturally occur in pneumatic systems within hose connectors or valves. Numerical results are compared to a CFD parameter study to verify the one dimensional simulation.