Given the importance of simulation techniques in automotive engineering, there is a lack of implementation regarding these techniques in the acoustics of damping materials for air-borne sound. Biot’s calculations have proven its abilities to simulate the acoustic characteristics of these damping materials. However, the characterisation of essential structural parameters, such as Young’s modulus and loss factor, in order to conduct Biot’s calculations have been inconclusive. Thus, the primary research objective of this study is to propose a new measurement system for the structural Biot parameters. After a comprehensive literature review has been undertaken on damping materials, as well as measurement apparatuses for Young’s modulus and loss factor of damping materials, two causes of measurement errors have been identified. Unknown stresses in measurement apparatuses and inhomogeneous, polytrophic and viscoelastic behaviour of specimens. A new measurement system that does not affect the specimens with unknown stresses and accounts for their complex behaviour required investigation. Non-contact ultrasound had been selected as a solution to determine the aforementioned parameters, since these methods do not necessarily touch or compress the specimen, which led to unknown stresses and neglection of the complex specimen behaviour with the aforementioned techniques. Although ultrasound had been used to determine structural parameters on various types of materials, it has never been used to measure soft porous damping materials. In order to find possible solutions, various sources using ultrasonics to investigate struc- tural parameters had been reviewed. In order to calculate structural parameters, the longitudinal and transversal wave velocity inside the specimen had to be determined. The main findings showed that non-contact ultrasound will be able to evaluate the Young’s modulus, loss factor as well as Poisson’s ratio. Consequently, it was shown that longitudinal velocity measurements could be conducted using well known transmission measurements. However, well known approaches would not be sufficient measuring the transversal wave velocity in soft damping materials. This problem was addressed with a special gas to be used, with lower sound speed velocity in the fluid than in the solid. Moreso, a new method determining the transversal wave velocity had been found, as it would enable the use of an even larger range of damping materials, especially ones with heavy frames and lower porosity. It will use refracted waves inside the specimen and the determination of the convertion position of the transversal to the longitudinal wave at the rear specimen surface. At the end of the study, hardware components were selected and a test rig was constructed, which should be able to prove that a determination of structural Biot parameters with non-contact ultrasound is possible with less errors instead of using mechanical transfer function systems. The development of measurement software as well as the testing of the measurement system and its validation was not under investigation in this dissertation. This study has expanded on the body of literature knowledge regarding non-contact ultrasound. Furthermore, a significant contribution has been made towards a new measurement system measuring Young’s modulus and loss factor which circumvents errors in mechanical transfer function systems. This will contribute to more precise simulations of damping materials and damped enclosures, which may ultimately result in enhanced efficiency of damping materials as well as the acoustic packaging of cars.

Using three years of daily streamflow and meteorological data from the Similkameen watershed at Princeton, B.C., the model parameters of the existing deterministic UBC Budget Model are evaluated. With these model parameters and the available meteorological data, the synthetic streamflow sequences are generated for the other seven years for the Similkameen watershed. These are subsequently compared with the actual flows. A separate statistical stochastic model is developed by using the spectral analysis, and the three years of the same daily flows are decomposed into 30 sub-harmonics or Fourier coefficients. By interpolating the Fourier coefficients and by estimating the anticipated mean annual flows from the snowpack data at Blackwall Peak, the synthetic traces of the daily streamflow sequences are simulated for the other seven years. A first order Markovian model is used to explain the random component. The comparative study is then carried out between the actual daily streamflow sequences and those generated by the deterministic UBC Budget Model and the stochastic spectral model. In comparison with the stochastic spectral model, good fits are obtained with the fixed model parameters of the UBC Budget Model for the sequence of peaks for the simulated hydro-graphs of the intervening years. Since the winter melt factor in the UBC Budget Model was assumed to be a constant for this analysis, some errors occur between the actual and the generated cumulative volumes. With the deterministic periodic component of the spectral model, the reconciliation between the cumulative volumes is fairly well maintained. Since the role of operational hydrology is not concerned with the prediction of actual flows, the stochastic spectral model should be judged on its ability in presenting the designer with a series of synthetic traces that are likely to occur during the lifetime of a particular project. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

An arbitrary continuous system model can be constructed on a Graphic Display by interacting with a light pen and dials. The user is presented with a control language and a menu on the Graphic Display, which uses pre-defined symbols to design a Continuous System Model. After constructing the model he wants to simulate, the user can assign appropriate variable names and values to the symbols, direct flow of information or material between components, can assign mathematical relationships between the components of a model, and can sketch graphical functions (x-y relationships) on the Graphic Display with the help of cross-hairs. The model, when built, can be saved on disk. In order to make modifications to the model at later time, a previously saved model can be restored. Changes such as altering values, mathematical relationships, and the deletion or addition cf components can be made before rerunning a simulation. Once the user is satisfied with the model description phase and when his model is complete, a CSBP program for that model is written onto disk, which can then be compiled and run in order to obtain the results for the specified variables in tabulated form. As visual aids, plots against Time can also be observed on the Graphic Display or can be plotted cn an X-Y plotter. The CAB system presented here provides an interactive tool for the design, modification and experimentation with Continuous System Models. As such it can enhance the modeller's representation and understanding of reality. / Science, Faculty of / Computer Science, Department of / Graduate

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This thesis presents a model for predicting the forced convective critical heat flux (CHF) for water over a wide range of thermal-hydraulic conditions which might be encountered during normal and accident operations of a light water nuclear reactor. The model is primarily composed from existing steady-state CHF correlations for tubes or tube and rod bundle geometries, and encompasses the following parametric ranges: 0.3 ≤ P (MPa) ≤ 16.0 6.0 ≤ D (mm) ≤ 30.0 100.0 ≤ G (kg/m2s) ≤ 8000.0 -0.30 ≤ X ≤ 1.0 The correlations used as the foundation of this model are the 1) Westinghouse-3 2) Biasi correlation, and the 3) Modified Barnett correlation The mode 1 presented is comp a red with available data, and the resultant model is illustrated as a 3-D surface in mass flux, quality, and CHF space to represent general CHF behavior.

This study develops a methodology for the analysis of Part Task Trainer (PTT) refresh scheduling used in conjunction with large simulators. A human performance model is defined through the development of descriptive equations and system random variables. PTT scheduling calculations are performed by employing a computer program simulation. The computer algorithm generates a set of random vectors to represent the learning characteristics of a sample group of individual trainees. The relationships between simulator scheduling time, PTT frequency training, and model variables are demonstrated to be user interactive. This will allow the PTT refresh scheduling program to be used as an analytical tool for the investigator and training planner. A computer summary of the resulting simulator retraining times with PTT refresh is provided to the user.

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