Optirnal utilization of production facilities is an important factor in field development planning and production forecasting. The problem may for instanee con sist of finding an optimal allocation of available gas or water handling capacity to ensure maximum oil production. Normally, this optimization is done on a day-byday basis. However, a bad strategy at an early stage of production may be devastating for the late time production from the field. In this paper, a method for optimizing net present value of oil production with respect to the well production rates as functions of time over the whole life time of the field is presented. A fully implicit, 3-D black-oil simulator is used to obtain the forward solution. The optimization algorithm is based on the optimal control theory approach, which facilitates a fast calculation of the objective function gradient with respect to pressures and constraints on the oil, water and gas production rates at well and group level. Well bottom-hole pressures are used as control parameters.

The problem of honeycomb sandwich structures with moisture ingression can be avoided by replacing the honeycombs through chevron-folded cores. The application to real aircraft components often requires wedgeshaped sandwich. With folded cores, this kind of geometric shape can be obtained only by special folding schemes which have a significant influence on the mechanical performance. A comprehensive experimental investigation of the relation between folding geometry and structural properties of wedge-shaped folded cores (WSFC) is very time consuming and expensive. Therefore, a procedure based on numerical methods has been developed to predict the structural response of this kind of cores under compressive and shear loading. The approach is based on a numerical tool that provides finite element models of arbitrary WSFC as well as the explicit finite element solver LS-DYNA for simulation. These tools were applied to investigate the influence of the inner core geometry and different materials on the mechanical properties of WSFC structures. To verify these results, a test programme was conducted. Test samples were manufactured using a newly developed folding process. Also special test devices to determine the compression and shear properties of the WSFC specimens were developed. The achieved test results show a good agreement with the behaviour predicted by simulation.

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