The Distortion of Pulses in Fluidic Transmission Lines

The distortion and attenuation of pulses in fluidic transmission lines was the subject of an investigation involving the computerised method of characteristics and the electrical transmission line analogy.
A test rig utilizing two conduits of differing dimensions and using air as the moving fluid was employed to investigate the phenomenon and test the computing procedures.
For the transmission of a single pulse along both conduits, a comparison of the computed and observed results showed excellent agreement while the electrical analogy was accurate for the larger conduit and less accurate for the smaller one, predicting considerably less attenuation than actually occurred in the latter case.
For the transmission of a train of pulses the computed results were less accurate but generally predicted the correct shape and magnitude.
It Was found that additional sophistication of the computer program, with reference to boundary condition modelling would be required to improve the correlation. It was concluded that it would be difficult to apply the electrical analogy to the pulse train case without further investigations into the reflection characteristics of the input and terminal configurations.
The results have provided a considerable insight into the investigated phenomenon and should find application in fluidic circuit design.