A Fluid Transmission Line Model For Use With ODE Simulators

Robert Piché
Dept. of Mathematics
Tampere University of Technology

Asko Ellman
Institute of Hydraulics and Automation
Tampere University of Technology

Eighth Bath International Fluid Power Workshop, Sept. 21-22, 1995, University of Bath, UK. To appear in Innovations in Fluid Power 8, edited by C. R. Burrows and K. A. Edge, Research Studies Press, Somerset, England, 1996.


A rational transfer function model for pressure and flow dynamics in rigid uniform fluid transsmission lines is presented. A decoupling transformation gives efficient simulation code. Either the one-dimensional linear resistance flow PDE or the two-dimensional viscous flow PDE can be approximated, the latter without recourse to Bessel functions. Parameters can also be assigned based on experimental frequency-response data. The model's implementation in both transfer function and state-space form is detailed. SIMULINK code is provided. Comparisons with published experimental test results and with the differential-delay model of Krus et al. are made.

Postscript document.