Interfacial instabilities of immiscible radial displacements in homogeneous porous media are analysed in the case of sinusoidal injection flows. The analysis is carried out through numerical simulations based on the immersed interface and level set methods. Investigations of the effects of the period of the sinusoidal injection flows revealed a novel resonance effect where, for a critical period, the number of fingers as well as their structures are considerably changed. The resonance in the flow development is clearly identified through the abrupt changes in the Fourier spectrum of the interface as well as quantitative characteristics of the flow in the form of the minimum and maximum radii of the interface. For the range of parameters examined in this study that correspond to instabilities dominated by viscous forces, the resonance period was found to correlate with a characteristic time of the flow and the fluids mobility ratio. This new physical phenomenon offers new perspectives for using the flow instability to determine important physical properties such as the viscosity and the surface tension of fluids.

Flow displacements in homogeneous porous media can result in instabilities at the interface between the fluids. Such instabilities may dramatically affect the overall efficiency of the displacement process and often need to be controlled. Flows that involve time-dependent injection schemes are analyzed to determine their effects on the growth of instabilities and the nonlinear development of finger structures in immiscible displacements. Predictions for monotonic and cyclic schemes in radial displacements are presented and compared with their constant injection counterpart. Moreover a controlled injection scheme that allows minimizing the instabilities is proposed. A hybrid model accounting for the discontinuities across the interface is implemented, and the problem is solved numerically. The effects of different parameters including the phase shift, amplitude, and period as well as the role of the mobility ratio and surface tension are discussed. A set of injection policies are observed to lead to the strongest attenuation of instabilities. Moreover, optimal phase shifts for cyclic displacements can result in the strongest enhancement or attenuation of the instability, depending on whether the flow involves extraction. A novel approach, referred to as the controlled injection scheme, has also been proposed and analyzed. In this scheme the flow is continuously adjusted in response to the growth rate of the instabilities resulting in a better capability of suppressing the development and growth of fingers.

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Nowadays functional verification of large system-on-chip has taken about 70% to 80% of the total design effort. The large amount of IP's of current SoC's makes the work of verification engineers quite hard due to the need to guarantee that the design is bug free before it is sent to tape out. In order to reduce the time spent in the functional verification and support the verification engineers, this work proposes a Hardware Abstract Layer (HAL) generator. The HAL generator is part of a methodology for SoC functional verification, which is supported by IP-XACT and aims to automate the functional verification flow. The HAL generator is able for creating C functions that allow the manipulation of registers and their fields at a very high abstraction level allowing the verification engineers to write their test cases without need to worrying about masks, macros, define and/or pointers manipulation.

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