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Wave interaction with a rubble-mound breakwater has been studied experimentally in the thesis. The breakwater may contain multi-layer anisotropic but homogeneous media. Fluid outside the porous layer field is assumed to incompressible and viscous,and the flow field is irrational. The study applies the velocity potential to describe the wave field with small amplitude incident wave. Under the consideration of linearity, Analytical solution is solved from boundary value program by the method of separation of variables. It bases on dispersion equation. Try to find the range and position of the complex eigenvalues in each porous column and to solve the velocity potential in the field by numerical methods. Wave reflection, transmission, and energy dissipation with a rubble-mound breakwater have been investigated experimentally, and consider the wave close linear wave theory, the wave steepness smaller than 0.035. Three different sizes of grain are used to construct the porous base, they are 16mm, 25mm, and 35mm, respectively. Single and double layers of porous base are considered. Some of the reflection coefficient are convergence, but they are the unreasonable results. Maybe the trouble is in the process of the computation with determination of .eigenvalues. When the wave has long period, the double-layer porous model reduces more wave energy, when the wave has short period, the single-layer porous and the smaller porous material model can disappears more wave energy. The characteristic of internal resistance in the porous has the difference along with the wave period. When the model crest is higher than the sea level, the consumption of wave energy are more when it is shorter along with the wave period. As a submerged breakwater, the effect for disappears wave energy to be limited.

There have been significant advances in the research of nanoparticle technologies for formation evaluation and reservoir engineering operations. The target applications require a variety of different retention characteristics ranging from nanoparticles that adsorb near the wellbore to nanoparticles that can travel significant distances within the porous medium with little or no retention on the grain substrate. A detailed understanding of the underlying mechanisms that cause nanoparticle retention is necessary to design these applications. In this thesis, experiments were conducted to quantify nanoparticle retention in unconsolidated columns packed with crushed Boise sandstone and kaolinite clay. Experimental parameters such as flow rate, injected concentration and sandpack composition were varied in a controlled fashion to test hypotheses concerning retention mechanisms and enable development and validation of a mathematical model of nanoparticle transport. Results indicate nanoparticle retention, defined as the concentration of nanoparticles remaining attached to grains in the porous medium after a volume of nanoparticle dispersion is injected through the medium and then displaced with brine, is a function of injected fluid velocity with higher injected velocities leading to lower retention. In many cases nanoparticle retention increased nonlinearly with increasing concentration of nanoparticles in the injected dispersion. Nanoparticle retention concentration was found to exhibit an upper bound beyond which no further adsorption from the nanoparticle dispersion to the grain substrate occurred. Kaolinite clay was shown to exhibit lower retention concentration [mg/m2] than Boise sandstone suggesting DLVO interactions do not significantly influence nanoparticle retention in high salinity dynamic flow environments. / text

This study investigates peculiarities of the filtration combustion (FC) of the gaseous fuel-air mixtures in a porous inertia media (PIM). Combustion wave velocities and temperatures were measured for hydrogen-air, propane-air and methane-air mixtures in the PIM at different mixture filtration velocities. It is shown that the dependences of the combustion wave velocities on the equivalence ratio are V-shaped, It was further confirmed that the FC in the PIM has more contrasts than similarities with the normal homogeneous combustion. One of the interesting observations in the present study, which is not common in normal homogenous combustion, is the shifting of the fuel-air equivalent ratio at the minimum combustion wave velocity from the stoichiometric condition (¢ = 1). For a hydrogen-air mixture, the fuel-air equivalence ratio at the minimum combustion velocity shifts from the stoichiometric condition to the rich region, while for the propane-air and methane-air mixtures the fuel-air equivalence ratio at the minimum combustion velocity shifts toward fuel-leaner conditions. The measured maximum porous media temperatures in the combustion waves are found to be weakly dependent on the mixture filtration velocities. In general, the effects of the mixture filtration velocities on the measured maximum porous media temperatures are not significant.

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No description available.