Water is one of the most biologically and economically important substances on Earth. A significant portion of Earth's water subsists in the subsurface. Our ability to monitor the flow and transport of water and other fluids through this unseen environment is crucial for a myriad of reasons.
One difficulty we...
In this paper we develop an upscaling technique for non-Darcy flow in porous media. Non-Darcy model of flow applies to flow in porous media when large velocities occur. The well-posedness results for theory of quasilinear elliptic partial differential equations. To discretize the model we used lowest order Raviart-Thomas mixed finite...
The Horsetail Creek (HC) bridge is an example of an Oregon bridge that was classified as structurally deficient and was not designed to withstand earthquake (EQ) excitations. A fiber-reinforced polymer (FRP) rehabilitation was performed on the HC bridge to increase flexural and shear capacities for traffic loads. However, a seismic...
The parallel implementation of a large number of functional units is necessary for
any industrial scale microfluidic process. The concept of a 'numbering up'
strategy where a single highly optimized functional unit that has a low individual
production is replicated a large number of times to create a device that...
In granular or fibrous materials, in which the dimensions of the internal
structure can be of the same order of magnitude as major flaws or holes, classical
elasticity theory does not consistently provide accurate models of the large stress
gradients that may develop. With the incorporation of additional rotational degrees...
A significant barrier to the diffusion bonding of large (i.e. 600 mm) microchannel devices is the large capital investment required to setup production. This large capital investment extends from long heating and cooling cycles leading to poor production
capacities. Empirical studies in industry have shown that cooling rate is limited...
Wachspress rational functions are ratios of polynomials having certain properties which make them good candidates for basis functions in finite element methods. In addition. it had been theorized that Wachspress rational weight functions should Provide a full-resolution discretization of the neutral particle transport equation in thick diffusive regions, but this...
An analysis method for moving loads computes the internal demand history in a structural member at integration points of force-based finite elements as opposed to the end forces of a refined displacement-based finite element mesh. The force-based formulation satisfies strong equilibrium of internal section forces with the element end forces...
Large numbers of 1950's vintage conventionally reinforced concrete (CRC) bridges remain in-service in the national bridge inventory. Many of these bridges are lightly reinforced for shear. Evaluation of these bridges to prevent unnecessary and costly repairs requires refined analytical techniques. This dissertation presents finite element (FE) modeling and comparisons of...
Brushless Doubly Fed Machines (BDFM) have potential advantages in variable
speed generation and adjustable speed drive applications. The most significant of these
advantages is a reduction in the power electronic converter rating, and therefore a
reduction in overall system cost. Presently, efforts are being directed at optimizing the
design of...