Prediction of the dynamic response of complex transmission line systems for unsteady pressure measurements

Abstract

Among the measurement and control systems of gas turbine engines, a recent new issue is the possibility of performing unsteady pressure measurements to detect flow anomalies in an engine or to evaluate loads on aerodynamic surfaces. A possible answer to this demand could be extending the use of well known and widely used transmission line systems, which have been applied so far to steady monitoring, to unsteady measurements thanks to proper dynamic modeling and compensation. Despite the huge number of models existing in the literature, a novel method has been developed, which is at the same time easy-to-handle, flexible and capable of reproducing the actual physics of the problem. Furthermore, the new model is able to deal with arbitrary complex networks of lines and cavities, and thus its applicability is not limited to series-connected systems. The main objectives of this paper are to show the derivation of the model, its validation against experimental tests and example of its applicability.

An Experimental and Theoretical Investigation of Wave Propagation in Teflon and Nylon Tubing With Methods to Prevent Aliasing in Pressure Scanners

“…Historically, such dynamic characterization has been achieved through a speaker which can generate dynamic pressures at a range of frequencies but only at low peak to peak pressures, typically on the order of tens of Pa [7,8]. Historically, such dynamic characterization has been achieved through a speaker which can generate dynamic pressures at a range of frequencies but only at low peak to peak pressures, typically on the order of tens of Pa [7,8].…”

“…Bergh and Tijdeman, Stinson, Bansevicius and Kargaudas along with others have done substantial work on the fundamental physics that drives the dynamic response of pressure measuring systems [3,7,[10][11][12][13][14][15]. Bergh and Tijdeman, Stinson, Bansevicius and Kargaudas along with others have done substantial work on the fundamental physics that drives the dynamic response of pressure measuring systems [3,7,[10][11][12][13][14][15].…”

“…(2) Plugging this equation back into the momentum equation the velocity equation can be derived. As demonstrated by Antonini et al the effects from heat transfer can be approximated within the model without simultaneously solving the equations of continuity, momentum, and energy but instead by simply including Bansevicius and Kargaudas' dissipation equation, adiss [7,11,12], which is shown in Eq. 6, below, such that a closed form solution in the frequency domain can be derived.…”

A novel measurement method of temperature model for bioreactor

“…For finding the delay, the model of measurement temperature can be determined by parametric system identification of the third expression of Eq. (12). Substituting the third expression of Eq.…”

“…A basic model for the prediction of the dynamic response of complex pneumatic line systems is presented in Ref. [12], which is able to reproduce the physics of the problem correctly and deal with any complex network of lines and cavities. In Ref.…”