Sensitivity Analysis and Experimental Validation of Plunger-type Wavemakers Modelled with a Steady Flow

Abstract

The inclusion of a steady flow in a water channel is a critical requirement for recreating accurately scaled ocean environments in a laboratory. In this thesis, the effect of a uniform flow on the theoretical model and experimental performance of a plungertype wavemaker has been investigated. Through a variance-based global sensitivity analysis, the influence of all input parameters on the output variance of the theoretical model was investigated. The analysis determined that the wave frequency had the highest influence on the wavemaker model. For a uniform flow, the first order and total effect sensitivity indices were estimated as 0.74±0.30% and 6.84±0.16%, respectively.Although the sensitivity of the model to the flow was relatively low compared to the wave frequency, there exists an impact due to the interaction of the flow parameter with the remaining model parameters. Therefore, it was established that the inclusion of the flow in the plunger-type wavemaker model is essential for application of the model to an experimental system. To investigate the performance of an experimental plunger-type wavemaker, an ultrasonic sensor was used to measure the generated wave profile for a variety of testing conditions based on the results of the sensitivity analysis. It was observed that as the difference between the experimental results and the theoretical model increased, both frequency and flow increased. Therefore, a corrected model was suggested and the operational range of the experimental system was established.The author acknowledges the support of Dr. Rishad Irani of the Multi-Domain Laboratory at Carleton University, Camilla Jastrzebski for her assistance with the conductive wave gauge, as well as the support of research peers, family, and friends throughout the research process.The author acknowledges the support of the Natural Sciences and Engineering Research Council of Canada (NSERC). Additionally, the author would like to acknowledge Mitacs as support for the work was maintained through a Research Training Award (RTA), Kraken Robotics for their support with the hardware development, and Carleton University for the equipment infrastructure.