A numerical technique is developed to determine the three‐dimensional fiber orientation in complex flows. The fiber orientation state is specified in terms of orientation tensors, which are used in several constitutive models. This method is applied to quasi‐steady state Hele‐Shaw flows in order to predict the flow‐induced fiber orientation during injection molding at zero volume fraction limit. At the inlet, a number of fibers are introduced at a specified rate into the flow and each fiber location is traced during the mold filling. Along these determined paths, the independent components of fourth order orientation tensors are solved, describing the orientation state. The numerical grid generation technique, which is suitable for complex mold shapes, is employed for the flow solution. Orientation ellipsoids are calculated from the second order tensors and are used to present the fiber orientation results. The numerical solutions are obtained for channel and converging flows. Planar, longitudinal, and transverse orientation results are generated from the orthogonal projections of the orientation ellipsoids.

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As the petroleum industry is facing challenges to add more oil reserves in their book, greater emphasis has been placed on improving the ultimate recovery factor for oilfields. When the recovery from primary and secondary methods could not be improved further, enhanced oil recovery (EOR) generally will be sought as the last option. One of the techniques applied in EOR is known as surfactant flooding. Though surfactants are very effective for the incremental oil recovery, there are implications during the post-flooding process. EOR surfactants that derived from petrochemicals generally display negative effects towards the marine ecosystem. This initial study aims to evaluate the potential application of palm oil based methyl ester sulfonate (MES) as a possible candidate for EOR application. Three qualitative and quantitative tests were performed on MES to evaluate its properties and capabilities for application in a specific offshore field. The results obtained from the qualitative compatibility and stability tests show that this anionic surfactant has great stability and compatibility with the brine solution as there are no visible signs of precipitation formation. However, the qualitative phase behavior test results indicated that the surfactant solution although has the ability to react with the crude oil but not at the required micro-emulsion state. In addition, the quantitative interfacial tension (IFT) test results also verified and supported the phase behavior test results where the strength of the MES was not adequate as a single surfactant system to achieve the ultra-low IFT state.

The flow of reacting monomers into thin planar cavities of irregular geometry is analyzed. The Hele-Shaw approximations are used to simplify the momentum and mass balances. At each time step, the flow domain is mapped onto a rectangular domain using elliptic expressions. The transformed governing equations are solved using finite-differences. The transient three-dimensional energy and species balances are solved using an explicit marching scheme coupled to the flow. Viscosity is modeled as a function of temperature and extent of reaction. Castro's model is used to compare several fountain flow approximations. A simplified algorithm was found to capture the essence of the fountain flow kinematics. The fountain flow approximations described here can also be used in thermoplastic injection molding modeling. Results for a rectangular end gated mold and for an irregular mold geometry are presented.

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