In this thesis techniques for characterizing wave propagation in flow ducts, previously mainly used for industrial applications, are adapted for internal biological flows. The main application in mind is blood vessels but could just as well be used for example for the respiratory system. With this method, the vessel is seen as a multiport characterized by the chosen state variables at the inlet and outlet. This approach not only yields information about the vessel itself (such as elasticity or abnormalities) but also allows highly efficient low-order modeling of parts of, or the complete, circulatory system. This thesis specifically evaluates the ability of the multiport method to obtain the pulse wave velocity of vessel phantoms and the experimental considerations that are best suited to acquire them. The initial experiments were set up in the MWL laboratory using air as a medium rather than water. These experiments used standard microphones and a conventional approach to the multiport, permitting a step-by-step approach that could be validated against similar experiments and theory. A test section where the vessel phantom could be either confined (to allow for varying intramural pressures) or radiating freely was constructed. Results for three tubes with different elasticities will be presented. A second test was performed at the Fluid Physics Laboratory with water as a medium. These experiments were done with the novel use of strain gauges in the place of microphones. This method gave several advantages and disadvantages that will be discussed in the thesis along with the results obtained for the vessel phantom.