Practical Engineering Analysis Research Articles

Alternative formulations of the boundary element method for potential and elastic zoned problems

The use of the subregion technique is a common way to deal with potential and elastic zoned problems by the boundary element method. Although this procedure has been successfully applied in many practical engineering analyses, nonlinear solutions can be easily deteriorated in the presence of an increasing number of discretized interface lines. This paper presents an appropriate formulation to model this kind of problem, avoiding some interface approximations, and reducing, therefore, the possible errors in the final solution.

Compaction Within the South Belridge Diatomite

Summary Compaction is incorporated into a field-scale finite-difference thermal simulator to allow practical engineering analysis of reservoir compaction caused by fluid withdrawal. Capabilities new to petroleum applications include hysteresis in the form of limited rebound during fluid injection and the concept of relaxation time (i.e., creep).

Suspended Solids Analysis of Estuarine Systems

A steady-state analysis of the distribution of suspended solids in estuaries has been developed and applied to the Sacramento-San Joaquin Delta, the James and the Rappahannock Rivers. The method is based on a simplified analysis of the density-driven circulation in estuaries, resulting in a two-layered flow pattern, with the surface layer flowing seaward, the bottom layer landward, and a vertical flow between the layers for continuity. These transport coefficients, with the vertical dispersion coefficient, permit calculation of the longitudinal distribution of salinity in the two layers. The settling velocity, assigned on the basis of size and density measurements of the particles, is included in the transport equation to determine the distribution of suspended solids. Comparisons of the calculated profiles with the observed values of solids concentrations indicate good agreement and demonstrate the general validity of the approach as a practical engineering analysis.